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1 /*
2  * Copyright (C) 2003-2004 The FFmpeg project
3  * Copyright (C) 2019 Peter Ross
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * On2 VP3/VP4 Video Decoder
25  *
26  * VP3 Video Decoder by Mike Melanson (mike at multimedia.cx)
27  * For more information about the VP3 coding process, visit:
28  *   http://wiki.multimedia.cx/index.php?title=On2_VP3
29  *
30  * Theora decoder by Alex Beregszaszi
31  */
32 
33 #include "config_components.h"
34 
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 
39 #include "libavutil/imgutils.h"
40 #include "libavutil/mem_internal.h"
41 
42 #include "avcodec.h"
43 #include "codec_internal.h"
44 #include "get_bits.h"
45 #include "hpeldsp.h"
46 #include "internal.h"
47 #include "mathops.h"
48 #include "thread.h"
49 #include "threadframe.h"
50 #include "videodsp.h"
51 #include "vp3data.h"
52 #include "vp4data.h"
53 #include "vp3dsp.h"
54 #include "xiph.h"
55 
56 #define VP3_MV_VLC_BITS     6
57 #define VP4_MV_VLC_BITS     6
58 #define SUPERBLOCK_VLC_BITS 6
59 
60 #define FRAGMENT_PIXELS 8
61 
62 // FIXME split things out into their own arrays
63 typedef struct Vp3Fragment {
64     int16_t dc;
65     uint8_t coding_method;
66     uint8_t qpi;
67 } Vp3Fragment;
68 
69 #define SB_NOT_CODED        0
70 #define SB_PARTIALLY_CODED  1
71 #define SB_FULLY_CODED      2
72 
73 // This is the maximum length of a single long bit run that can be encoded
74 // for superblock coding or block qps. Theora special-cases this to read a
75 // bit instead of flipping the current bit to allow for runs longer than 4129.
76 #define MAXIMUM_LONG_BIT_RUN 4129
77 
78 #define MODE_INTER_NO_MV      0
79 #define MODE_INTRA            1
80 #define MODE_INTER_PLUS_MV    2
81 #define MODE_INTER_LAST_MV    3
82 #define MODE_INTER_PRIOR_LAST 4
83 #define MODE_USING_GOLDEN     5
84 #define MODE_GOLDEN_MV        6
85 #define MODE_INTER_FOURMV     7
86 #define CODING_MODE_COUNT     8
87 
88 /* special internal mode */
89 #define MODE_COPY             8
90 
91 static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb);
92 static int theora_decode_tables(AVCodecContext *avctx, GetBitContext *gb);
93 
94 
95 /* There are 6 preset schemes, plus a free-form scheme */
96 static const int ModeAlphabet[6][CODING_MODE_COUNT] = {
97     /* scheme 1: Last motion vector dominates */
98     { MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,
99       MODE_INTER_PLUS_MV,    MODE_INTER_NO_MV,
100       MODE_INTRA,            MODE_USING_GOLDEN,
101       MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
102 
103     /* scheme 2 */
104     { MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,
105       MODE_INTER_NO_MV,      MODE_INTER_PLUS_MV,
106       MODE_INTRA,            MODE_USING_GOLDEN,
107       MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
108 
109     /* scheme 3 */
110     { MODE_INTER_LAST_MV,    MODE_INTER_PLUS_MV,
111       MODE_INTER_PRIOR_LAST, MODE_INTER_NO_MV,
112       MODE_INTRA,            MODE_USING_GOLDEN,
113       MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
114 
115     /* scheme 4 */
116     { MODE_INTER_LAST_MV,    MODE_INTER_PLUS_MV,
117       MODE_INTER_NO_MV,      MODE_INTER_PRIOR_LAST,
118       MODE_INTRA,            MODE_USING_GOLDEN,
119       MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
120 
121     /* scheme 5: No motion vector dominates */
122     { MODE_INTER_NO_MV,      MODE_INTER_LAST_MV,
123       MODE_INTER_PRIOR_LAST, MODE_INTER_PLUS_MV,
124       MODE_INTRA,            MODE_USING_GOLDEN,
125       MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
126 
127     /* scheme 6 */
128     { MODE_INTER_NO_MV,      MODE_USING_GOLDEN,
129       MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,
130       MODE_INTER_PLUS_MV,    MODE_INTRA,
131       MODE_GOLDEN_MV,        MODE_INTER_FOURMV },
132 };
133 
134 static const uint8_t hilbert_offset[16][2] = {
135     { 0, 0 }, { 1, 0 }, { 1, 1 }, { 0, 1 },
136     { 0, 2 }, { 0, 3 }, { 1, 3 }, { 1, 2 },
137     { 2, 2 }, { 2, 3 }, { 3, 3 }, { 3, 2 },
138     { 3, 1 }, { 2, 1 }, { 2, 0 }, { 3, 0 }
139 };
140 
141 enum {
142     VP4_DC_INTRA  = 0,
143     VP4_DC_INTER  = 1,
144     VP4_DC_GOLDEN = 2,
145     NB_VP4_DC_TYPES,
146     VP4_DC_UNDEFINED = NB_VP4_DC_TYPES
147 };
148 
149 static const uint8_t vp4_pred_block_type_map[8] = {
150     [MODE_INTER_NO_MV]      = VP4_DC_INTER,
151     [MODE_INTRA]            = VP4_DC_INTRA,
152     [MODE_INTER_PLUS_MV]    = VP4_DC_INTER,
153     [MODE_INTER_LAST_MV]    = VP4_DC_INTER,
154     [MODE_INTER_PRIOR_LAST] = VP4_DC_INTER,
155     [MODE_USING_GOLDEN]     = VP4_DC_GOLDEN,
156     [MODE_GOLDEN_MV]        = VP4_DC_GOLDEN,
157     [MODE_INTER_FOURMV]     = VP4_DC_INTER,
158 };
159 
160 typedef struct {
161     int dc;
162     int type;
163 } VP4Predictor;
164 
165 #define MIN_DEQUANT_VAL 2
166 
167 typedef struct HuffEntry {
168     uint8_t len, sym;
169 } HuffEntry;
170 
171 typedef struct HuffTable {
172     HuffEntry entries[32];
173     uint8_t   nb_entries;
174 } HuffTable;
175 
176 typedef struct Vp3DecodeContext {
177     AVCodecContext *avctx;
178     int theora, theora_tables, theora_header;
179     int version;
180     int width, height;
181     int chroma_x_shift, chroma_y_shift;
182     ThreadFrame golden_frame;
183     ThreadFrame last_frame;
184     ThreadFrame current_frame;
185     int keyframe;
186     uint8_t idct_permutation[64];
187     uint8_t idct_scantable[64];
188     HpelDSPContext hdsp;
189     VideoDSPContext vdsp;
190     VP3DSPContext vp3dsp;
191     DECLARE_ALIGNED(16, int16_t, block)[64];
192     int flipped_image;
193     int last_slice_end;
194     int skip_loop_filter;
195 
196     int qps[3];
197     int nqps;
198     int last_qps[3];
199 
200     int superblock_count;
201     int y_superblock_width;
202     int y_superblock_height;
203     int y_superblock_count;
204     int c_superblock_width;
205     int c_superblock_height;
206     int c_superblock_count;
207     int u_superblock_start;
208     int v_superblock_start;
209     unsigned char *superblock_coding;
210 
211     int macroblock_count; /* y macroblock count */
212     int macroblock_width;
213     int macroblock_height;
214     int c_macroblock_count;
215     int c_macroblock_width;
216     int c_macroblock_height;
217     int yuv_macroblock_count; /* y+u+v macroblock count */
218 
219     int fragment_count;
220     int fragment_width[2];
221     int fragment_height[2];
222 
223     Vp3Fragment *all_fragments;
224     int fragment_start[3];
225     int data_offset[3];
226     uint8_t offset_x;
227     uint8_t offset_y;
228     int offset_x_warned;
229 
230     int8_t (*motion_val[2])[2];
231 
232     /* tables */
233     uint16_t coded_dc_scale_factor[2][64];
234     uint32_t coded_ac_scale_factor[64];
235     uint8_t base_matrix[384][64];
236     uint8_t qr_count[2][3];
237     uint8_t qr_size[2][3][64];
238     uint16_t qr_base[2][3][64];
239 
240     /**
241      * This is a list of all tokens in bitstream order. Reordering takes place
242      * by pulling from each level during IDCT. As a consequence, IDCT must be
243      * in Hilbert order, making the minimum slice height 64 for 4:2:0 and 32
244      * otherwise. The 32 different tokens with up to 12 bits of extradata are
245      * collapsed into 3 types, packed as follows:
246      *   (from the low to high bits)
247      *
248      * 2 bits: type (0,1,2)
249      *   0: EOB run, 14 bits for run length (12 needed)
250      *   1: zero run, 7 bits for run length
251      *                7 bits for the next coefficient (3 needed)
252      *   2: coefficient, 14 bits (11 needed)
253      *
254      * Coefficients are signed, so are packed in the highest bits for automatic
255      * sign extension.
256      */
257     int16_t *dct_tokens[3][64];
258     int16_t *dct_tokens_base;
259 #define TOKEN_EOB(eob_run)              ((eob_run) << 2)
260 #define TOKEN_ZERO_RUN(coeff, zero_run) (((coeff) * 512) + ((zero_run) << 2) + 1)
261 #define TOKEN_COEFF(coeff)              (((coeff) * 4) + 2)
262 
263     /**
264      * number of blocks that contain DCT coefficients at
265      * the given level or higher
266      */
267     int num_coded_frags[3][64];
268     int total_num_coded_frags;
269 
270     /* this is a list of indexes into the all_fragments array indicating
271      * which of the fragments are coded */
272     int *coded_fragment_list[3];
273 
274     int *kf_coded_fragment_list;
275     int *nkf_coded_fragment_list;
276     int num_kf_coded_fragment[3];
277 
278     /* The first 16 of the following VLCs are for the dc coefficients;
279        the others are four groups of 16 VLCs each for ac coefficients. */
280     VLC coeff_vlc[5 * 16];
281 
282     VLC superblock_run_length_vlc; /* version < 2 */
283     VLC fragment_run_length_vlc; /* version < 2 */
284     VLC block_pattern_vlc[2]; /* version >= 2*/
285     VLC mode_code_vlc;
286     VLC motion_vector_vlc; /* version < 2 */
287     VLC vp4_mv_vlc[2][7]; /* version >=2 */
288 
289     /* these arrays need to be on 16-byte boundaries since SSE2 operations
290      * index into them */
291     DECLARE_ALIGNED(16, int16_t, qmat)[3][2][3][64];     ///< qmat[qpi][is_inter][plane]
292 
293     /* This table contains superblock_count * 16 entries. Each set of 16
294      * numbers corresponds to the fragment indexes 0..15 of the superblock.
295      * An entry will be -1 to indicate that no entry corresponds to that
296      * index. */
297     int *superblock_fragments;
298 
299     /* This is an array that indicates how a particular macroblock
300      * is coded. */
301     unsigned char *macroblock_coding;
302 
303     uint8_t *edge_emu_buffer;
304 
305     /* Huffman decode */
306     HuffTable huffman_table[5 * 16];
307 
308     uint8_t filter_limit_values[64];
309     DECLARE_ALIGNED(8, int, bounding_values_array)[256 + 2];
310 
311     VP4Predictor * dc_pred_row; /* dc_pred_row[y_superblock_width * 4] */
312 } Vp3DecodeContext;
313 
314 /************************************************************************
315  * VP3 specific functions
316  ************************************************************************/
317 
free_tables(AVCodecContext * avctx)318 static av_cold void free_tables(AVCodecContext *avctx)
319 {
320     Vp3DecodeContext *s = avctx->priv_data;
321 
322     av_freep(&s->superblock_coding);
323     av_freep(&s->all_fragments);
324     av_freep(&s->nkf_coded_fragment_list);
325     av_freep(&s->kf_coded_fragment_list);
326     av_freep(&s->dct_tokens_base);
327     av_freep(&s->superblock_fragments);
328     av_freep(&s->macroblock_coding);
329     av_freep(&s->dc_pred_row);
330     av_freep(&s->motion_val[0]);
331     av_freep(&s->motion_val[1]);
332 }
333 
vp3_decode_flush(AVCodecContext * avctx)334 static void vp3_decode_flush(AVCodecContext *avctx)
335 {
336     Vp3DecodeContext *s = avctx->priv_data;
337 
338     if (s->golden_frame.f)
339         ff_thread_release_ext_buffer(avctx, &s->golden_frame);
340     if (s->last_frame.f)
341         ff_thread_release_ext_buffer(avctx, &s->last_frame);
342     if (s->current_frame.f)
343         ff_thread_release_ext_buffer(avctx, &s->current_frame);
344 }
345 
vp3_decode_end(AVCodecContext * avctx)346 static av_cold int vp3_decode_end(AVCodecContext *avctx)
347 {
348     Vp3DecodeContext *s = avctx->priv_data;
349     int i, j;
350 
351     free_tables(avctx);
352     av_freep(&s->edge_emu_buffer);
353 
354     s->theora_tables = 0;
355 
356     /* release all frames */
357     vp3_decode_flush(avctx);
358     av_frame_free(&s->current_frame.f);
359     av_frame_free(&s->last_frame.f);
360     av_frame_free(&s->golden_frame.f);
361 
362     for (i = 0; i < FF_ARRAY_ELEMS(s->coeff_vlc); i++)
363         ff_free_vlc(&s->coeff_vlc[i]);
364 
365     ff_free_vlc(&s->superblock_run_length_vlc);
366     ff_free_vlc(&s->fragment_run_length_vlc);
367     ff_free_vlc(&s->mode_code_vlc);
368     ff_free_vlc(&s->motion_vector_vlc);
369 
370     for (j = 0; j < 2; j++)
371         for (i = 0; i < 7; i++)
372             ff_free_vlc(&s->vp4_mv_vlc[j][i]);
373 
374     for (i = 0; i < 2; i++)
375         ff_free_vlc(&s->block_pattern_vlc[i]);
376     return 0;
377 }
378 
379 /**
380  * This function sets up all of the various blocks mappings:
381  * superblocks <-> fragments, macroblocks <-> fragments,
382  * superblocks <-> macroblocks
383  *
384  * @return 0 is successful; returns 1 if *anything* went wrong.
385  */
init_block_mapping(Vp3DecodeContext * s)386 static int init_block_mapping(Vp3DecodeContext *s)
387 {
388     int sb_x, sb_y, plane;
389     int x, y, i, j = 0;
390 
391     for (plane = 0; plane < 3; plane++) {
392         int sb_width    = plane ? s->c_superblock_width
393                                 : s->y_superblock_width;
394         int sb_height   = plane ? s->c_superblock_height
395                                 : s->y_superblock_height;
396         int frag_width  = s->fragment_width[!!plane];
397         int frag_height = s->fragment_height[!!plane];
398 
399         for (sb_y = 0; sb_y < sb_height; sb_y++)
400             for (sb_x = 0; sb_x < sb_width; sb_x++)
401                 for (i = 0; i < 16; i++) {
402                     x = 4 * sb_x + hilbert_offset[i][0];
403                     y = 4 * sb_y + hilbert_offset[i][1];
404 
405                     if (x < frag_width && y < frag_height)
406                         s->superblock_fragments[j++] = s->fragment_start[plane] +
407                                                        y * frag_width + x;
408                     else
409                         s->superblock_fragments[j++] = -1;
410                 }
411     }
412 
413     return 0;  /* successful path out */
414 }
415 
416 /*
417  * This function sets up the dequantization tables used for a particular
418  * frame.
419  */
init_dequantizer(Vp3DecodeContext * s,int qpi)420 static void init_dequantizer(Vp3DecodeContext *s, int qpi)
421 {
422     int ac_scale_factor = s->coded_ac_scale_factor[s->qps[qpi]];
423     int i, plane, inter, qri, bmi, bmj, qistart;
424 
425     for (inter = 0; inter < 2; inter++) {
426         for (plane = 0; plane < 3; plane++) {
427             int dc_scale_factor = s->coded_dc_scale_factor[!!plane][s->qps[qpi]];
428             int sum = 0;
429             for (qri = 0; qri < s->qr_count[inter][plane]; qri++) {
430                 sum += s->qr_size[inter][plane][qri];
431                 if (s->qps[qpi] <= sum)
432                     break;
433             }
434             qistart = sum - s->qr_size[inter][plane][qri];
435             bmi     = s->qr_base[inter][plane][qri];
436             bmj     = s->qr_base[inter][plane][qri + 1];
437             for (i = 0; i < 64; i++) {
438                 int coeff = (2 * (sum     - s->qps[qpi]) * s->base_matrix[bmi][i] -
439                              2 * (qistart - s->qps[qpi]) * s->base_matrix[bmj][i] +
440                              s->qr_size[inter][plane][qri]) /
441                             (2 * s->qr_size[inter][plane][qri]);
442 
443                 int qmin   = 8 << (inter + !i);
444                 int qscale = i ? ac_scale_factor : dc_scale_factor;
445                 int qbias = (1 + inter) * 3;
446                 s->qmat[qpi][inter][plane][s->idct_permutation[i]] =
447                     (i == 0 || s->version < 2) ? av_clip((qscale * coeff) / 100 * 4, qmin, 4096)
448                                                : (qscale * (coeff - qbias) / 100 + qbias) * 4;
449             }
450             /* all DC coefficients use the same quant so as not to interfere
451              * with DC prediction */
452             s->qmat[qpi][inter][plane][0] = s->qmat[0][inter][plane][0];
453         }
454     }
455 }
456 
457 /*
458  * This function initializes the loop filter boundary limits if the frame's
459  * quality index is different from the previous frame's.
460  *
461  * The filter_limit_values may not be larger than 127.
462  */
init_loop_filter(Vp3DecodeContext * s)463 static void init_loop_filter(Vp3DecodeContext *s)
464 {
465     ff_vp3dsp_set_bounding_values(s->bounding_values_array, s->filter_limit_values[s->qps[0]]);
466 }
467 
468 /*
469  * This function unpacks all of the superblock/macroblock/fragment coding
470  * information from the bitstream.
471  */
unpack_superblocks(Vp3DecodeContext * s,GetBitContext * gb)472 static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb)
473 {
474     int superblock_starts[3] = {
475         0, s->u_superblock_start, s->v_superblock_start
476     };
477     int bit = 0;
478     int current_superblock = 0;
479     int current_run = 0;
480     int num_partial_superblocks = 0;
481 
482     int i, j;
483     int current_fragment;
484     int plane;
485     int plane0_num_coded_frags = 0;
486 
487     if (s->keyframe) {
488         memset(s->superblock_coding, SB_FULLY_CODED, s->superblock_count);
489     } else {
490         /* unpack the list of partially-coded superblocks */
491         bit         = get_bits1(gb) ^ 1;
492         current_run = 0;
493 
494         while (current_superblock < s->superblock_count && get_bits_left(gb) > 0) {
495             if (s->theora && current_run == MAXIMUM_LONG_BIT_RUN)
496                 bit = get_bits1(gb);
497             else
498                 bit ^= 1;
499 
500             current_run = get_vlc2(gb, s->superblock_run_length_vlc.table,
501                                    SUPERBLOCK_VLC_BITS, 2);
502             if (current_run == 34)
503                 current_run += get_bits(gb, 12);
504 
505             if (current_run > s->superblock_count - current_superblock) {
506                 av_log(s->avctx, AV_LOG_ERROR,
507                        "Invalid partially coded superblock run length\n");
508                 return -1;
509             }
510 
511             memset(s->superblock_coding + current_superblock, bit, current_run);
512 
513             current_superblock += current_run;
514             if (bit)
515                 num_partial_superblocks += current_run;
516         }
517 
518         /* unpack the list of fully coded superblocks if any of the blocks were
519          * not marked as partially coded in the previous step */
520         if (num_partial_superblocks < s->superblock_count) {
521             int superblocks_decoded = 0;
522 
523             current_superblock = 0;
524             bit                = get_bits1(gb) ^ 1;
525             current_run        = 0;
526 
527             while (superblocks_decoded < s->superblock_count - num_partial_superblocks &&
528                    get_bits_left(gb) > 0) {
529                 if (s->theora && current_run == MAXIMUM_LONG_BIT_RUN)
530                     bit = get_bits1(gb);
531                 else
532                     bit ^= 1;
533 
534                 current_run = get_vlc2(gb, s->superblock_run_length_vlc.table,
535                                        SUPERBLOCK_VLC_BITS, 2);
536                 if (current_run == 34)
537                     current_run += get_bits(gb, 12);
538 
539                 for (j = 0; j < current_run; current_superblock++) {
540                     if (current_superblock >= s->superblock_count) {
541                         av_log(s->avctx, AV_LOG_ERROR,
542                                "Invalid fully coded superblock run length\n");
543                         return -1;
544                     }
545 
546                     /* skip any superblocks already marked as partially coded */
547                     if (s->superblock_coding[current_superblock] == SB_NOT_CODED) {
548                         s->superblock_coding[current_superblock] = 2 * bit;
549                         j++;
550                     }
551                 }
552                 superblocks_decoded += current_run;
553             }
554         }
555 
556         /* if there were partial blocks, initialize bitstream for
557          * unpacking fragment codings */
558         if (num_partial_superblocks) {
559             current_run = 0;
560             bit         = get_bits1(gb);
561             /* toggle the bit because as soon as the first run length is
562              * fetched the bit will be toggled again */
563             bit ^= 1;
564         }
565     }
566 
567     /* figure out which fragments are coded; iterate through each
568      * superblock (all planes) */
569     s->total_num_coded_frags = 0;
570     memset(s->macroblock_coding, MODE_COPY, s->macroblock_count);
571 
572     s->coded_fragment_list[0] = s->keyframe ? s->kf_coded_fragment_list
573                                             : s->nkf_coded_fragment_list;
574 
575     for (plane = 0; plane < 3; plane++) {
576         int sb_start = superblock_starts[plane];
577         int sb_end   = sb_start + (plane ? s->c_superblock_count
578                                          : s->y_superblock_count);
579         int num_coded_frags = 0;
580 
581         if (s->keyframe) {
582             if (s->num_kf_coded_fragment[plane] == -1) {
583                 for (i = sb_start; i < sb_end; i++) {
584                     /* iterate through all 16 fragments in a superblock */
585                     for (j = 0; j < 16; j++) {
586                         /* if the fragment is in bounds, check its coding status */
587                         current_fragment = s->superblock_fragments[i * 16 + j];
588                         if (current_fragment != -1) {
589                             s->coded_fragment_list[plane][num_coded_frags++] =
590                                 current_fragment;
591                         }
592                     }
593                 }
594                 s->num_kf_coded_fragment[plane] = num_coded_frags;
595             } else
596                 num_coded_frags = s->num_kf_coded_fragment[plane];
597         } else {
598             for (i = sb_start; i < sb_end && get_bits_left(gb) > 0; i++) {
599                 if (get_bits_left(gb) < plane0_num_coded_frags >> 2) {
600                     return AVERROR_INVALIDDATA;
601                 }
602                 /* iterate through all 16 fragments in a superblock */
603                 for (j = 0; j < 16; j++) {
604                     /* if the fragment is in bounds, check its coding status */
605                     current_fragment = s->superblock_fragments[i * 16 + j];
606                     if (current_fragment != -1) {
607                         int coded = s->superblock_coding[i];
608 
609                         if (coded == SB_PARTIALLY_CODED) {
610                             /* fragment may or may not be coded; this is the case
611                              * that cares about the fragment coding runs */
612                             if (current_run-- == 0) {
613                                 bit        ^= 1;
614                                 current_run = get_vlc2(gb, s->fragment_run_length_vlc.table, 5, 2);
615                             }
616                             coded = bit;
617                         }
618 
619                         if (coded) {
620                             /* default mode; actual mode will be decoded in
621                              * the next phase */
622                             s->all_fragments[current_fragment].coding_method =
623                                 MODE_INTER_NO_MV;
624                             s->coded_fragment_list[plane][num_coded_frags++] =
625                                 current_fragment;
626                         } else {
627                             /* not coded; copy this fragment from the prior frame */
628                             s->all_fragments[current_fragment].coding_method =
629                                 MODE_COPY;
630                         }
631                     }
632                 }
633             }
634         }
635         if (!plane)
636             plane0_num_coded_frags = num_coded_frags;
637         s->total_num_coded_frags += num_coded_frags;
638         for (i = 0; i < 64; i++)
639             s->num_coded_frags[plane][i] = num_coded_frags;
640         if (plane < 2)
641             s->coded_fragment_list[plane + 1] = s->coded_fragment_list[plane] +
642                                                 num_coded_frags;
643     }
644     return 0;
645 }
646 
647 #define BLOCK_X (2 * mb_x + (k & 1))
648 #define BLOCK_Y (2 * mb_y + (k >> 1))
649 
650 #if CONFIG_VP4_DECODER
651 /**
652  * @return number of blocks, or > yuv_macroblock_count on error.
653  *         return value is always >= 1.
654  */
vp4_get_mb_count(Vp3DecodeContext * s,GetBitContext * gb)655 static int vp4_get_mb_count(Vp3DecodeContext *s, GetBitContext *gb)
656 {
657     int v = 1;
658     int bits;
659     while ((bits = show_bits(gb, 9)) == 0x1ff) {
660         skip_bits(gb, 9);
661         v += 256;
662         if (v > s->yuv_macroblock_count) {
663             av_log(s->avctx, AV_LOG_ERROR, "Invalid run length\n");
664             return v;
665         }
666     }
667 #define body(n) { \
668     skip_bits(gb, 2 + n); \
669     v += (1 << n) + get_bits(gb, n); }
670 #define thresh(n) (0x200 - (0x80 >> n))
671 #define else_if(n) else if (bits < thresh(n)) body(n)
672     if (bits < 0x100) {
673         skip_bits(gb, 1);
674     } else if (bits < thresh(0)) {
675         skip_bits(gb, 2);
676         v += 1;
677     }
678     else_if(1)
679     else_if(2)
680     else_if(3)
681     else_if(4)
682     else_if(5)
683     else_if(6)
684     else body(7)
685 #undef body
686 #undef thresh
687 #undef else_if
688     return v;
689 }
690 
vp4_get_block_pattern(Vp3DecodeContext * s,GetBitContext * gb,int * next_block_pattern_table)691 static int vp4_get_block_pattern(Vp3DecodeContext *s, GetBitContext *gb, int *next_block_pattern_table)
692 {
693     int v = get_vlc2(gb, s->block_pattern_vlc[*next_block_pattern_table].table, 3, 2);
694     *next_block_pattern_table = vp4_block_pattern_table_selector[v];
695     return v + 1;
696 }
697 
vp4_unpack_macroblocks(Vp3DecodeContext * s,GetBitContext * gb)698 static int vp4_unpack_macroblocks(Vp3DecodeContext *s, GetBitContext *gb)
699 {
700     int plane, i, j, k, fragment;
701     int next_block_pattern_table;
702     int bit, current_run, has_partial;
703 
704     memset(s->macroblock_coding, MODE_COPY, s->macroblock_count);
705 
706     if (s->keyframe)
707         return 0;
708 
709     has_partial = 0;
710     bit         = get_bits1(gb);
711     for (i = 0; i < s->yuv_macroblock_count; i += current_run) {
712         if (get_bits_left(gb) <= 0)
713             return AVERROR_INVALIDDATA;
714         current_run = vp4_get_mb_count(s, gb);
715         if (current_run > s->yuv_macroblock_count - i)
716             return -1;
717         memset(s->superblock_coding + i, 2 * bit, current_run);
718         bit ^= 1;
719         has_partial |= bit;
720     }
721 
722     if (has_partial) {
723         if (get_bits_left(gb) <= 0)
724             return AVERROR_INVALIDDATA;
725         bit  = get_bits1(gb);
726         current_run = vp4_get_mb_count(s, gb);
727         for (i = 0; i < s->yuv_macroblock_count; i++) {
728             if (!s->superblock_coding[i]) {
729                 if (!current_run) {
730                     bit ^= 1;
731                     current_run = vp4_get_mb_count(s, gb);
732                 }
733                 s->superblock_coding[i] = bit;
734                 current_run--;
735             }
736         }
737         if (current_run) /* handle situation when vp4_get_mb_count() fails */
738             return -1;
739     }
740 
741     next_block_pattern_table = 0;
742     i = 0;
743     for (plane = 0; plane < 3; plane++) {
744         int sb_x, sb_y;
745         int sb_width = plane ? s->c_superblock_width : s->y_superblock_width;
746         int sb_height = plane ? s->c_superblock_height : s->y_superblock_height;
747         int mb_width = plane ? s->c_macroblock_width : s->macroblock_width;
748         int mb_height = plane ? s->c_macroblock_height : s->macroblock_height;
749         int fragment_width = s->fragment_width[!!plane];
750         int fragment_height = s->fragment_height[!!plane];
751 
752         for (sb_y = 0; sb_y < sb_height; sb_y++) {
753             for (sb_x = 0; sb_x < sb_width; sb_x++) {
754                 for (j = 0; j < 4; j++) {
755                     int mb_x = 2 * sb_x + (j >> 1);
756                     int mb_y = 2 * sb_y + (j >> 1) ^ (j & 1);
757                     int mb_coded, pattern, coded;
758 
759                     if (mb_x >= mb_width || mb_y >= mb_height)
760                         continue;
761 
762                     mb_coded = s->superblock_coding[i++];
763 
764                     if (mb_coded == SB_FULLY_CODED)
765                         pattern = 0xF;
766                     else if (mb_coded == SB_PARTIALLY_CODED)
767                         pattern = vp4_get_block_pattern(s, gb, &next_block_pattern_table);
768                     else
769                         pattern = 0;
770 
771                     for (k = 0; k < 4; k++) {
772                         if (BLOCK_X >= fragment_width || BLOCK_Y >= fragment_height)
773                             continue;
774                         fragment = s->fragment_start[plane] + BLOCK_Y * fragment_width + BLOCK_X;
775                         coded = pattern & (8 >> k);
776                         /* MODE_INTER_NO_MV is the default for coded fragments.
777                            the actual method is decoded in the next phase. */
778                         s->all_fragments[fragment].coding_method = coded ? MODE_INTER_NO_MV : MODE_COPY;
779                     }
780                 }
781             }
782         }
783     }
784     return 0;
785 }
786 #endif
787 
788 /*
789  * This function unpacks all the coding mode data for individual macroblocks
790  * from the bitstream.
791  */
unpack_modes(Vp3DecodeContext * s,GetBitContext * gb)792 static int unpack_modes(Vp3DecodeContext *s, GetBitContext *gb)
793 {
794     int i, j, k, sb_x, sb_y;
795     int scheme;
796     int current_macroblock;
797     int current_fragment;
798     int coding_mode;
799     int custom_mode_alphabet[CODING_MODE_COUNT];
800     const int *alphabet;
801     Vp3Fragment *frag;
802 
803     if (s->keyframe) {
804         for (i = 0; i < s->fragment_count; i++)
805             s->all_fragments[i].coding_method = MODE_INTRA;
806     } else {
807         /* fetch the mode coding scheme for this frame */
808         scheme = get_bits(gb, 3);
809 
810         /* is it a custom coding scheme? */
811         if (scheme == 0) {
812             for (i = 0; i < 8; i++)
813                 custom_mode_alphabet[i] = MODE_INTER_NO_MV;
814             for (i = 0; i < 8; i++)
815                 custom_mode_alphabet[get_bits(gb, 3)] = i;
816             alphabet = custom_mode_alphabet;
817         } else
818             alphabet = ModeAlphabet[scheme - 1];
819 
820         /* iterate through all of the macroblocks that contain 1 or more
821          * coded fragments */
822         for (sb_y = 0; sb_y < s->y_superblock_height; sb_y++) {
823             for (sb_x = 0; sb_x < s->y_superblock_width; sb_x++) {
824                 if (get_bits_left(gb) <= 0)
825                     return -1;
826 
827                 for (j = 0; j < 4; j++) {
828                     int mb_x = 2 * sb_x + (j >> 1);
829                     int mb_y = 2 * sb_y + (((j >> 1) + j) & 1);
830                     current_macroblock = mb_y * s->macroblock_width + mb_x;
831 
832                     if (mb_x >= s->macroblock_width ||
833                         mb_y >= s->macroblock_height)
834                         continue;
835 
836                     /* coding modes are only stored if the macroblock has
837                      * at least one luma block coded, otherwise it must be
838                      * INTER_NO_MV */
839                     for (k = 0; k < 4; k++) {
840                         current_fragment = BLOCK_Y *
841                                            s->fragment_width[0] + BLOCK_X;
842                         if (s->all_fragments[current_fragment].coding_method != MODE_COPY)
843                             break;
844                     }
845                     if (k == 4) {
846                         s->macroblock_coding[current_macroblock] = MODE_INTER_NO_MV;
847                         continue;
848                     }
849 
850                     /* mode 7 means get 3 bits for each coding mode */
851                     if (scheme == 7)
852                         coding_mode = get_bits(gb, 3);
853                     else
854                         coding_mode = alphabet[get_vlc2(gb, s->mode_code_vlc.table, 3, 3)];
855 
856                     s->macroblock_coding[current_macroblock] = coding_mode;
857                     for (k = 0; k < 4; k++) {
858                         frag = s->all_fragments + BLOCK_Y * s->fragment_width[0] + BLOCK_X;
859                         if (frag->coding_method != MODE_COPY)
860                             frag->coding_method = coding_mode;
861                     }
862 
863 #define SET_CHROMA_MODES                                                      \
864     if (frag[s->fragment_start[1]].coding_method != MODE_COPY)                \
865         frag[s->fragment_start[1]].coding_method = coding_mode;               \
866     if (frag[s->fragment_start[2]].coding_method != MODE_COPY)                \
867         frag[s->fragment_start[2]].coding_method = coding_mode;
868 
869                     if (s->chroma_y_shift) {
870                         frag = s->all_fragments + mb_y *
871                                s->fragment_width[1] + mb_x;
872                         SET_CHROMA_MODES
873                     } else if (s->chroma_x_shift) {
874                         frag = s->all_fragments +
875                                2 * mb_y * s->fragment_width[1] + mb_x;
876                         for (k = 0; k < 2; k++) {
877                             SET_CHROMA_MODES
878                             frag += s->fragment_width[1];
879                         }
880                     } else {
881                         for (k = 0; k < 4; k++) {
882                             frag = s->all_fragments +
883                                    BLOCK_Y * s->fragment_width[1] + BLOCK_X;
884                             SET_CHROMA_MODES
885                         }
886                     }
887                 }
888             }
889         }
890     }
891 
892     return 0;
893 }
894 
vp4_get_mv(Vp3DecodeContext * s,GetBitContext * gb,int axis,int last_motion)895 static int vp4_get_mv(Vp3DecodeContext *s, GetBitContext *gb, int axis, int last_motion)
896 {
897     int v = get_vlc2(gb, s->vp4_mv_vlc[axis][vp4_mv_table_selector[FFABS(last_motion)]].table,
898                      VP4_MV_VLC_BITS, 2);
899     return last_motion < 0 ? -v : v;
900 }
901 
902 /*
903  * This function unpacks all the motion vectors for the individual
904  * macroblocks from the bitstream.
905  */
unpack_vectors(Vp3DecodeContext * s,GetBitContext * gb)906 static int unpack_vectors(Vp3DecodeContext *s, GetBitContext *gb)
907 {
908     int j, k, sb_x, sb_y;
909     int coding_mode;
910     int motion_x[4];
911     int motion_y[4];
912     int last_motion_x = 0;
913     int last_motion_y = 0;
914     int prior_last_motion_x = 0;
915     int prior_last_motion_y = 0;
916     int last_gold_motion_x = 0;
917     int last_gold_motion_y = 0;
918     int current_macroblock;
919     int current_fragment;
920     int frag;
921 
922     if (s->keyframe)
923         return 0;
924 
925     /* coding mode 0 is the VLC scheme; 1 is the fixed code scheme; 2 is VP4 code scheme */
926     coding_mode = s->version < 2 ? get_bits1(gb) : 2;
927 
928     /* iterate through all of the macroblocks that contain 1 or more
929      * coded fragments */
930     for (sb_y = 0; sb_y < s->y_superblock_height; sb_y++) {
931         for (sb_x = 0; sb_x < s->y_superblock_width; sb_x++) {
932             if (get_bits_left(gb) <= 0)
933                 return -1;
934 
935             for (j = 0; j < 4; j++) {
936                 int mb_x = 2 * sb_x + (j >> 1);
937                 int mb_y = 2 * sb_y + (((j >> 1) + j) & 1);
938                 current_macroblock = mb_y * s->macroblock_width + mb_x;
939 
940                 if (mb_x >= s->macroblock_width  ||
941                     mb_y >= s->macroblock_height ||
942                     s->macroblock_coding[current_macroblock] == MODE_COPY)
943                     continue;
944 
945                 switch (s->macroblock_coding[current_macroblock]) {
946                 case MODE_GOLDEN_MV:
947                     if (coding_mode == 2) { /* VP4 */
948                         last_gold_motion_x = motion_x[0] = vp4_get_mv(s, gb, 0, last_gold_motion_x);
949                         last_gold_motion_y = motion_y[0] = vp4_get_mv(s, gb, 1, last_gold_motion_y);
950                         break;
951                     } /* otherwise fall through */
952                 case MODE_INTER_PLUS_MV:
953                     /* all 6 fragments use the same motion vector */
954                     if (coding_mode == 0) {
955                         motion_x[0] = get_vlc2(gb, s->motion_vector_vlc.table,
956                                                VP3_MV_VLC_BITS, 2);
957                         motion_y[0] = get_vlc2(gb, s->motion_vector_vlc.table,
958                                                VP3_MV_VLC_BITS, 2);
959                     } else if (coding_mode == 1) {
960                         motion_x[0] = fixed_motion_vector_table[get_bits(gb, 6)];
961                         motion_y[0] = fixed_motion_vector_table[get_bits(gb, 6)];
962                     } else { /* VP4 */
963                         motion_x[0] = vp4_get_mv(s, gb, 0, last_motion_x);
964                         motion_y[0] = vp4_get_mv(s, gb, 1, last_motion_y);
965                     }
966 
967                     /* vector maintenance, only on MODE_INTER_PLUS_MV */
968                     if (s->macroblock_coding[current_macroblock] == MODE_INTER_PLUS_MV) {
969                         prior_last_motion_x = last_motion_x;
970                         prior_last_motion_y = last_motion_y;
971                         last_motion_x       = motion_x[0];
972                         last_motion_y       = motion_y[0];
973                     }
974                     break;
975 
976                 case MODE_INTER_FOURMV:
977                     /* vector maintenance */
978                     prior_last_motion_x = last_motion_x;
979                     prior_last_motion_y = last_motion_y;
980 
981                     /* fetch 4 vectors from the bitstream, one for each
982                      * Y fragment, then average for the C fragment vectors */
983                     for (k = 0; k < 4; k++) {
984                         current_fragment = BLOCK_Y * s->fragment_width[0] + BLOCK_X;
985                         if (s->all_fragments[current_fragment].coding_method != MODE_COPY) {
986                             if (coding_mode == 0) {
987                                 motion_x[k] = get_vlc2(gb, s->motion_vector_vlc.table,
988                                                        VP3_MV_VLC_BITS, 2);
989                                 motion_y[k] = get_vlc2(gb, s->motion_vector_vlc.table,
990                                                        VP3_MV_VLC_BITS, 2);
991                             } else if (coding_mode == 1) {
992                                 motion_x[k] = fixed_motion_vector_table[get_bits(gb, 6)];
993                                 motion_y[k] = fixed_motion_vector_table[get_bits(gb, 6)];
994                             } else { /* VP4 */
995                                 motion_x[k] = vp4_get_mv(s, gb, 0, prior_last_motion_x);
996                                 motion_y[k] = vp4_get_mv(s, gb, 1, prior_last_motion_y);
997                             }
998                             last_motion_x = motion_x[k];
999                             last_motion_y = motion_y[k];
1000                         } else {
1001                             motion_x[k] = 0;
1002                             motion_y[k] = 0;
1003                         }
1004                     }
1005                     break;
1006 
1007                 case MODE_INTER_LAST_MV:
1008                     /* all 6 fragments use the last motion vector */
1009                     motion_x[0] = last_motion_x;
1010                     motion_y[0] = last_motion_y;
1011 
1012                     /* no vector maintenance (last vector remains the
1013                      * last vector) */
1014                     break;
1015 
1016                 case MODE_INTER_PRIOR_LAST:
1017                     /* all 6 fragments use the motion vector prior to the
1018                      * last motion vector */
1019                     motion_x[0] = prior_last_motion_x;
1020                     motion_y[0] = prior_last_motion_y;
1021 
1022                     /* vector maintenance */
1023                     prior_last_motion_x = last_motion_x;
1024                     prior_last_motion_y = last_motion_y;
1025                     last_motion_x       = motion_x[0];
1026                     last_motion_y       = motion_y[0];
1027                     break;
1028 
1029                 default:
1030                     /* covers intra, inter without MV, golden without MV */
1031                     motion_x[0] = 0;
1032                     motion_y[0] = 0;
1033 
1034                     /* no vector maintenance */
1035                     break;
1036                 }
1037 
1038                 /* assign the motion vectors to the correct fragments */
1039                 for (k = 0; k < 4; k++) {
1040                     current_fragment =
1041                         BLOCK_Y * s->fragment_width[0] + BLOCK_X;
1042                     if (s->macroblock_coding[current_macroblock] == MODE_INTER_FOURMV) {
1043                         s->motion_val[0][current_fragment][0] = motion_x[k];
1044                         s->motion_val[0][current_fragment][1] = motion_y[k];
1045                     } else {
1046                         s->motion_val[0][current_fragment][0] = motion_x[0];
1047                         s->motion_val[0][current_fragment][1] = motion_y[0];
1048                     }
1049                 }
1050 
1051                 if (s->chroma_y_shift) {
1052                     if (s->macroblock_coding[current_macroblock] == MODE_INTER_FOURMV) {
1053                         motion_x[0] = RSHIFT(motion_x[0] + motion_x[1] +
1054                                              motion_x[2] + motion_x[3], 2);
1055                         motion_y[0] = RSHIFT(motion_y[0] + motion_y[1] +
1056                                              motion_y[2] + motion_y[3], 2);
1057                     }
1058                     if (s->version <= 2) {
1059                         motion_x[0] = (motion_x[0] >> 1) | (motion_x[0] & 1);
1060                         motion_y[0] = (motion_y[0] >> 1) | (motion_y[0] & 1);
1061                     }
1062                     frag = mb_y * s->fragment_width[1] + mb_x;
1063                     s->motion_val[1][frag][0] = motion_x[0];
1064                     s->motion_val[1][frag][1] = motion_y[0];
1065                 } else if (s->chroma_x_shift) {
1066                     if (s->macroblock_coding[current_macroblock] == MODE_INTER_FOURMV) {
1067                         motion_x[0] = RSHIFT(motion_x[0] + motion_x[1], 1);
1068                         motion_y[0] = RSHIFT(motion_y[0] + motion_y[1], 1);
1069                         motion_x[1] = RSHIFT(motion_x[2] + motion_x[3], 1);
1070                         motion_y[1] = RSHIFT(motion_y[2] + motion_y[3], 1);
1071                     } else {
1072                         motion_x[1] = motion_x[0];
1073                         motion_y[1] = motion_y[0];
1074                     }
1075                     if (s->version <= 2) {
1076                         motion_x[0] = (motion_x[0] >> 1) | (motion_x[0] & 1);
1077                         motion_x[1] = (motion_x[1] >> 1) | (motion_x[1] & 1);
1078                     }
1079                     frag = 2 * mb_y * s->fragment_width[1] + mb_x;
1080                     for (k = 0; k < 2; k++) {
1081                         s->motion_val[1][frag][0] = motion_x[k];
1082                         s->motion_val[1][frag][1] = motion_y[k];
1083                         frag += s->fragment_width[1];
1084                     }
1085                 } else {
1086                     for (k = 0; k < 4; k++) {
1087                         frag = BLOCK_Y * s->fragment_width[1] + BLOCK_X;
1088                         if (s->macroblock_coding[current_macroblock] == MODE_INTER_FOURMV) {
1089                             s->motion_val[1][frag][0] = motion_x[k];
1090                             s->motion_val[1][frag][1] = motion_y[k];
1091                         } else {
1092                             s->motion_val[1][frag][0] = motion_x[0];
1093                             s->motion_val[1][frag][1] = motion_y[0];
1094                         }
1095                     }
1096                 }
1097             }
1098         }
1099     }
1100 
1101     return 0;
1102 }
1103 
unpack_block_qpis(Vp3DecodeContext * s,GetBitContext * gb)1104 static int unpack_block_qpis(Vp3DecodeContext *s, GetBitContext *gb)
1105 {
1106     int qpi, i, j, bit, run_length, blocks_decoded, num_blocks_at_qpi;
1107     int num_blocks = s->total_num_coded_frags;
1108 
1109     for (qpi = 0; qpi < s->nqps - 1 && num_blocks > 0; qpi++) {
1110         i = blocks_decoded = num_blocks_at_qpi = 0;
1111 
1112         bit        = get_bits1(gb) ^ 1;
1113         run_length = 0;
1114 
1115         do {
1116             if (run_length == MAXIMUM_LONG_BIT_RUN)
1117                 bit = get_bits1(gb);
1118             else
1119                 bit ^= 1;
1120 
1121             run_length = get_vlc2(gb, s->superblock_run_length_vlc.table,
1122                                   SUPERBLOCK_VLC_BITS, 2);
1123             if (run_length == 34)
1124                 run_length += get_bits(gb, 12);
1125             blocks_decoded += run_length;
1126 
1127             if (!bit)
1128                 num_blocks_at_qpi += run_length;
1129 
1130             for (j = 0; j < run_length; i++) {
1131                 if (i >= s->total_num_coded_frags)
1132                     return -1;
1133 
1134                 if (s->all_fragments[s->coded_fragment_list[0][i]].qpi == qpi) {
1135                     s->all_fragments[s->coded_fragment_list[0][i]].qpi += bit;
1136                     j++;
1137                 }
1138             }
1139         } while (blocks_decoded < num_blocks && get_bits_left(gb) > 0);
1140 
1141         num_blocks -= num_blocks_at_qpi;
1142     }
1143 
1144     return 0;
1145 }
1146 
get_eob_run(GetBitContext * gb,int token)1147 static inline int get_eob_run(GetBitContext *gb, int token)
1148 {
1149     int v = eob_run_table[token].base;
1150     if (eob_run_table[token].bits)
1151         v += get_bits(gb, eob_run_table[token].bits);
1152     return v;
1153 }
1154 
get_coeff(GetBitContext * gb,int token,int16_t * coeff)1155 static inline int get_coeff(GetBitContext *gb, int token, int16_t *coeff)
1156 {
1157     int bits_to_get, zero_run;
1158 
1159     bits_to_get = coeff_get_bits[token];
1160     if (bits_to_get)
1161         bits_to_get = get_bits(gb, bits_to_get);
1162     *coeff = coeff_tables[token][bits_to_get];
1163 
1164     zero_run = zero_run_base[token];
1165     if (zero_run_get_bits[token])
1166         zero_run += get_bits(gb, zero_run_get_bits[token]);
1167 
1168     return zero_run;
1169 }
1170 
1171 /*
1172  * This function is called by unpack_dct_coeffs() to extract the VLCs from
1173  * the bitstream. The VLCs encode tokens which are used to unpack DCT
1174  * data. This function unpacks all the VLCs for either the Y plane or both
1175  * C planes, and is called for DC coefficients or different AC coefficient
1176  * levels (since different coefficient types require different VLC tables.
1177  *
1178  * This function returns a residual eob run. E.g, if a particular token gave
1179  * instructions to EOB the next 5 fragments and there were only 2 fragments
1180  * left in the current fragment range, 3 would be returned so that it could
1181  * be passed into the next call to this same function.
1182  */
unpack_vlcs(Vp3DecodeContext * s,GetBitContext * gb,VLC * table,int coeff_index,int plane,int eob_run)1183 static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb,
1184                        VLC *table, int coeff_index,
1185                        int plane,
1186                        int eob_run)
1187 {
1188     int i, j = 0;
1189     int token;
1190     int zero_run  = 0;
1191     int16_t coeff = 0;
1192     int blocks_ended;
1193     int coeff_i = 0;
1194     int num_coeffs      = s->num_coded_frags[plane][coeff_index];
1195     int16_t *dct_tokens = s->dct_tokens[plane][coeff_index];
1196 
1197     /* local references to structure members to avoid repeated dereferences */
1198     int *coded_fragment_list   = s->coded_fragment_list[plane];
1199     Vp3Fragment *all_fragments = s->all_fragments;
1200     const VLCElem *vlc_table = table->table;
1201 
1202     if (num_coeffs < 0) {
1203         av_log(s->avctx, AV_LOG_ERROR,
1204                "Invalid number of coefficients at level %d\n", coeff_index);
1205         return AVERROR_INVALIDDATA;
1206     }
1207 
1208     if (eob_run > num_coeffs) {
1209         coeff_i      =
1210         blocks_ended = num_coeffs;
1211         eob_run     -= num_coeffs;
1212     } else {
1213         coeff_i      =
1214         blocks_ended = eob_run;
1215         eob_run      = 0;
1216     }
1217 
1218     // insert fake EOB token to cover the split between planes or zzi
1219     if (blocks_ended)
1220         dct_tokens[j++] = blocks_ended << 2;
1221 
1222     while (coeff_i < num_coeffs && get_bits_left(gb) > 0) {
1223         /* decode a VLC into a token */
1224         token = get_vlc2(gb, vlc_table, 11, 3);
1225         /* use the token to get a zero run, a coefficient, and an eob run */
1226         if ((unsigned) token <= 6U) {
1227             eob_run = get_eob_run(gb, token);
1228             if (!eob_run)
1229                 eob_run = INT_MAX;
1230 
1231             // record only the number of blocks ended in this plane,
1232             // any spill will be recorded in the next plane.
1233             if (eob_run > num_coeffs - coeff_i) {
1234                 dct_tokens[j++] = TOKEN_EOB(num_coeffs - coeff_i);
1235                 blocks_ended   += num_coeffs - coeff_i;
1236                 eob_run        -= num_coeffs - coeff_i;
1237                 coeff_i         = num_coeffs;
1238             } else {
1239                 dct_tokens[j++] = TOKEN_EOB(eob_run);
1240                 blocks_ended   += eob_run;
1241                 coeff_i        += eob_run;
1242                 eob_run         = 0;
1243             }
1244         } else if (token >= 0) {
1245             zero_run = get_coeff(gb, token, &coeff);
1246 
1247             if (zero_run) {
1248                 dct_tokens[j++] = TOKEN_ZERO_RUN(coeff, zero_run);
1249             } else {
1250                 // Save DC into the fragment structure. DC prediction is
1251                 // done in raster order, so the actual DC can't be in with
1252                 // other tokens. We still need the token in dct_tokens[]
1253                 // however, or else the structure collapses on itself.
1254                 if (!coeff_index)
1255                     all_fragments[coded_fragment_list[coeff_i]].dc = coeff;
1256 
1257                 dct_tokens[j++] = TOKEN_COEFF(coeff);
1258             }
1259 
1260             if (coeff_index + zero_run > 64) {
1261                 av_log(s->avctx, AV_LOG_DEBUG,
1262                        "Invalid zero run of %d with %d coeffs left\n",
1263                        zero_run, 64 - coeff_index);
1264                 zero_run = 64 - coeff_index;
1265             }
1266 
1267             // zero runs code multiple coefficients,
1268             // so don't try to decode coeffs for those higher levels
1269             for (i = coeff_index + 1; i <= coeff_index + zero_run; i++)
1270                 s->num_coded_frags[plane][i]--;
1271             coeff_i++;
1272         } else {
1273             av_log(s->avctx, AV_LOG_ERROR, "Invalid token %d\n", token);
1274             return -1;
1275         }
1276     }
1277 
1278     if (blocks_ended > s->num_coded_frags[plane][coeff_index])
1279         av_log(s->avctx, AV_LOG_ERROR, "More blocks ended than coded!\n");
1280 
1281     // decrement the number of blocks that have higher coefficients for each
1282     // EOB run at this level
1283     if (blocks_ended)
1284         for (i = coeff_index + 1; i < 64; i++)
1285             s->num_coded_frags[plane][i] -= blocks_ended;
1286 
1287     // setup the next buffer
1288     if (plane < 2)
1289         s->dct_tokens[plane + 1][coeff_index] = dct_tokens + j;
1290     else if (coeff_index < 63)
1291         s->dct_tokens[0][coeff_index + 1] = dct_tokens + j;
1292 
1293     return eob_run;
1294 }
1295 
1296 static void reverse_dc_prediction(Vp3DecodeContext *s,
1297                                   int first_fragment,
1298                                   int fragment_width,
1299                                   int fragment_height);
1300 /*
1301  * This function unpacks all of the DCT coefficient data from the
1302  * bitstream.
1303  */
unpack_dct_coeffs(Vp3DecodeContext * s,GetBitContext * gb)1304 static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb)
1305 {
1306     int i;
1307     int dc_y_table;
1308     int dc_c_table;
1309     int ac_y_table;
1310     int ac_c_table;
1311     int residual_eob_run = 0;
1312     VLC *y_tables[64];
1313     VLC *c_tables[64];
1314 
1315     s->dct_tokens[0][0] = s->dct_tokens_base;
1316 
1317     if (get_bits_left(gb) < 16)
1318         return AVERROR_INVALIDDATA;
1319 
1320     /* fetch the DC table indexes */
1321     dc_y_table = get_bits(gb, 4);
1322     dc_c_table = get_bits(gb, 4);
1323 
1324     /* unpack the Y plane DC coefficients */
1325     residual_eob_run = unpack_vlcs(s, gb, &s->coeff_vlc[dc_y_table], 0,
1326                                    0, residual_eob_run);
1327     if (residual_eob_run < 0)
1328         return residual_eob_run;
1329     if (get_bits_left(gb) < 8)
1330         return AVERROR_INVALIDDATA;
1331 
1332     /* reverse prediction of the Y-plane DC coefficients */
1333     reverse_dc_prediction(s, 0, s->fragment_width[0], s->fragment_height[0]);
1334 
1335     /* unpack the C plane DC coefficients */
1336     residual_eob_run = unpack_vlcs(s, gb, &s->coeff_vlc[dc_c_table], 0,
1337                                    1, residual_eob_run);
1338     if (residual_eob_run < 0)
1339         return residual_eob_run;
1340     residual_eob_run = unpack_vlcs(s, gb, &s->coeff_vlc[dc_c_table], 0,
1341                                    2, residual_eob_run);
1342     if (residual_eob_run < 0)
1343         return residual_eob_run;
1344 
1345     /* reverse prediction of the C-plane DC coefficients */
1346     if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
1347         reverse_dc_prediction(s, s->fragment_start[1],
1348                               s->fragment_width[1], s->fragment_height[1]);
1349         reverse_dc_prediction(s, s->fragment_start[2],
1350                               s->fragment_width[1], s->fragment_height[1]);
1351     }
1352 
1353     if (get_bits_left(gb) < 8)
1354         return AVERROR_INVALIDDATA;
1355     /* fetch the AC table indexes */
1356     ac_y_table = get_bits(gb, 4);
1357     ac_c_table = get_bits(gb, 4);
1358 
1359     /* build tables of AC VLC tables */
1360     for (i = 1; i <= 5; i++) {
1361         /* AC VLC table group 1 */
1362         y_tables[i] = &s->coeff_vlc[ac_y_table + 16];
1363         c_tables[i] = &s->coeff_vlc[ac_c_table + 16];
1364     }
1365     for (i = 6; i <= 14; i++) {
1366         /* AC VLC table group 2 */
1367         y_tables[i] = &s->coeff_vlc[ac_y_table + 32];
1368         c_tables[i] = &s->coeff_vlc[ac_c_table + 32];
1369     }
1370     for (i = 15; i <= 27; i++) {
1371         /* AC VLC table group 3 */
1372         y_tables[i] = &s->coeff_vlc[ac_y_table + 48];
1373         c_tables[i] = &s->coeff_vlc[ac_c_table + 48];
1374     }
1375     for (i = 28; i <= 63; i++) {
1376         /* AC VLC table group 4 */
1377         y_tables[i] = &s->coeff_vlc[ac_y_table + 64];
1378         c_tables[i] = &s->coeff_vlc[ac_c_table + 64];
1379     }
1380 
1381     /* decode all AC coefficients */
1382     for (i = 1; i <= 63; i++) {
1383         residual_eob_run = unpack_vlcs(s, gb, y_tables[i], i,
1384                                        0, residual_eob_run);
1385         if (residual_eob_run < 0)
1386             return residual_eob_run;
1387 
1388         residual_eob_run = unpack_vlcs(s, gb, c_tables[i], i,
1389                                        1, residual_eob_run);
1390         if (residual_eob_run < 0)
1391             return residual_eob_run;
1392         residual_eob_run = unpack_vlcs(s, gb, c_tables[i], i,
1393                                        2, residual_eob_run);
1394         if (residual_eob_run < 0)
1395             return residual_eob_run;
1396     }
1397 
1398     return 0;
1399 }
1400 
1401 #if CONFIG_VP4_DECODER
1402 /**
1403  * eob_tracker[] is instead of TOKEN_EOB(value)
1404  * a dummy TOKEN_EOB(0) value is used to make vp3_dequant work
1405  *
1406  * @return < 0 on error
1407  */
vp4_unpack_vlcs(Vp3DecodeContext * s,GetBitContext * gb,VLC * vlc_tables[64],int plane,int eob_tracker[64],int fragment)1408 static int vp4_unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb,
1409                        VLC *vlc_tables[64],
1410                        int plane, int eob_tracker[64], int fragment)
1411 {
1412     int token;
1413     int zero_run  = 0;
1414     int16_t coeff = 0;
1415     int coeff_i = 0;
1416     int eob_run;
1417 
1418     while (!eob_tracker[coeff_i]) {
1419         if (get_bits_left(gb) < 1)
1420             return AVERROR_INVALIDDATA;
1421 
1422         token = get_vlc2(gb, vlc_tables[coeff_i]->table, 11, 3);
1423 
1424         /* use the token to get a zero run, a coefficient, and an eob run */
1425         if ((unsigned) token <= 6U) {
1426             eob_run = get_eob_run(gb, token);
1427             *s->dct_tokens[plane][coeff_i]++ = TOKEN_EOB(0);
1428             eob_tracker[coeff_i] = eob_run - 1;
1429             return 0;
1430         } else if (token >= 0) {
1431             zero_run = get_coeff(gb, token, &coeff);
1432 
1433             if (zero_run) {
1434                 if (coeff_i + zero_run > 64) {
1435                     av_log(s->avctx, AV_LOG_DEBUG,
1436                         "Invalid zero run of %d with %d coeffs left\n",
1437                         zero_run, 64 - coeff_i);
1438                     zero_run = 64 - coeff_i;
1439                 }
1440                 *s->dct_tokens[plane][coeff_i]++ = TOKEN_ZERO_RUN(coeff, zero_run);
1441                 coeff_i += zero_run;
1442             } else {
1443                 if (!coeff_i)
1444                     s->all_fragments[fragment].dc = coeff;
1445 
1446                 *s->dct_tokens[plane][coeff_i]++ = TOKEN_COEFF(coeff);
1447             }
1448             coeff_i++;
1449             if (coeff_i >= 64) /* > 64 occurs when there is a zero_run overflow */
1450                 return 0; /* stop */
1451         } else {
1452             av_log(s->avctx, AV_LOG_ERROR, "Invalid token %d\n", token);
1453             return -1;
1454         }
1455     }
1456     *s->dct_tokens[plane][coeff_i]++ = TOKEN_EOB(0);
1457     eob_tracker[coeff_i]--;
1458     return 0;
1459 }
1460 
vp4_dc_predictor_reset(VP4Predictor * p)1461 static void vp4_dc_predictor_reset(VP4Predictor *p)
1462 {
1463     p->dc = 0;
1464     p->type = VP4_DC_UNDEFINED;
1465 }
1466 
vp4_dc_pred_before(const Vp3DecodeContext * s,VP4Predictor dc_pred[6][6],int sb_x)1467 static void vp4_dc_pred_before(const Vp3DecodeContext *s, VP4Predictor dc_pred[6][6], int sb_x)
1468 {
1469     int i, j;
1470 
1471     for (i = 0; i < 4; i++)
1472         dc_pred[0][i + 1] = s->dc_pred_row[sb_x * 4 + i];
1473 
1474     for (j = 1; j < 5; j++)
1475         for (i = 0; i < 4; i++)
1476             vp4_dc_predictor_reset(&dc_pred[j][i + 1]);
1477 }
1478 
vp4_dc_pred_after(Vp3DecodeContext * s,VP4Predictor dc_pred[6][6],int sb_x)1479 static void vp4_dc_pred_after(Vp3DecodeContext *s, VP4Predictor dc_pred[6][6], int sb_x)
1480 {
1481     int i;
1482 
1483     for (i = 0; i < 4; i++)
1484         s->dc_pred_row[sb_x * 4 + i] = dc_pred[4][i + 1];
1485 
1486     for (i = 1; i < 5; i++)
1487         dc_pred[i][0] = dc_pred[i][4];
1488 }
1489 
1490 /* note: dc_pred points to the current block */
vp4_dc_pred(const Vp3DecodeContext * s,const VP4Predictor * dc_pred,const int * last_dc,int type,int plane)1491 static int vp4_dc_pred(const Vp3DecodeContext *s, const VP4Predictor * dc_pred, const int * last_dc, int type, int plane)
1492 {
1493     int count = 0;
1494     int dc = 0;
1495 
1496     if (dc_pred[-6].type == type) {
1497         dc += dc_pred[-6].dc;
1498         count++;
1499     }
1500 
1501     if (dc_pred[6].type == type) {
1502         dc += dc_pred[6].dc;
1503         count++;
1504     }
1505 
1506     if (count != 2 && dc_pred[-1].type == type) {
1507         dc += dc_pred[-1].dc;
1508         count++;
1509     }
1510 
1511     if (count != 2 && dc_pred[1].type == type) {
1512         dc += dc_pred[1].dc;
1513         count++;
1514     }
1515 
1516     /* using division instead of shift to correctly handle negative values */
1517     return count == 2 ? dc / 2 : last_dc[type];
1518 }
1519 
vp4_set_tokens_base(Vp3DecodeContext * s)1520 static void vp4_set_tokens_base(Vp3DecodeContext *s)
1521 {
1522     int plane, i;
1523     int16_t *base = s->dct_tokens_base;
1524     for (plane = 0; plane < 3; plane++) {
1525         for (i = 0; i < 64; i++) {
1526             s->dct_tokens[plane][i] = base;
1527             base += s->fragment_width[!!plane] * s->fragment_height[!!plane];
1528         }
1529     }
1530 }
1531 
vp4_unpack_dct_coeffs(Vp3DecodeContext * s,GetBitContext * gb)1532 static int vp4_unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb)
1533 {
1534     int i, j;
1535     int dc_y_table;
1536     int dc_c_table;
1537     int ac_y_table;
1538     int ac_c_table;
1539     VLC *tables[2][64];
1540     int plane, sb_y, sb_x;
1541     int eob_tracker[64];
1542     VP4Predictor dc_pred[6][6];
1543     int last_dc[NB_VP4_DC_TYPES];
1544 
1545     if (get_bits_left(gb) < 16)
1546         return AVERROR_INVALIDDATA;
1547 
1548     /* fetch the DC table indexes */
1549     dc_y_table = get_bits(gb, 4);
1550     dc_c_table = get_bits(gb, 4);
1551 
1552     ac_y_table = get_bits(gb, 4);
1553     ac_c_table = get_bits(gb, 4);
1554 
1555     /* build tables of DC/AC VLC tables */
1556 
1557     /* DC table group */
1558     tables[0][0] = &s->coeff_vlc[dc_y_table];
1559     tables[1][0] = &s->coeff_vlc[dc_c_table];
1560     for (i = 1; i <= 5; i++) {
1561         /* AC VLC table group 1 */
1562         tables[0][i] = &s->coeff_vlc[ac_y_table + 16];
1563         tables[1][i] = &s->coeff_vlc[ac_c_table + 16];
1564     }
1565     for (i = 6; i <= 14; i++) {
1566         /* AC VLC table group 2 */
1567         tables[0][i] = &s->coeff_vlc[ac_y_table + 32];
1568         tables[1][i] = &s->coeff_vlc[ac_c_table + 32];
1569     }
1570     for (i = 15; i <= 27; i++) {
1571         /* AC VLC table group 3 */
1572         tables[0][i] = &s->coeff_vlc[ac_y_table + 48];
1573         tables[1][i] = &s->coeff_vlc[ac_c_table + 48];
1574     }
1575     for (i = 28; i <= 63; i++) {
1576         /* AC VLC table group 4 */
1577         tables[0][i] = &s->coeff_vlc[ac_y_table + 64];
1578         tables[1][i] = &s->coeff_vlc[ac_c_table + 64];
1579     }
1580 
1581     vp4_set_tokens_base(s);
1582 
1583     memset(last_dc, 0, sizeof(last_dc));
1584 
1585     for (plane = 0; plane < ((s->avctx->flags & AV_CODEC_FLAG_GRAY) ? 1 : 3); plane++) {
1586         memset(eob_tracker, 0, sizeof(eob_tracker));
1587 
1588         /* initialise dc prediction */
1589         for (i = 0; i < s->fragment_width[!!plane]; i++)
1590             vp4_dc_predictor_reset(&s->dc_pred_row[i]);
1591 
1592         for (j = 0; j < 6; j++)
1593             for (i = 0; i < 6; i++)
1594                 vp4_dc_predictor_reset(&dc_pred[j][i]);
1595 
1596         for (sb_y = 0; sb_y * 4 < s->fragment_height[!!plane]; sb_y++) {
1597             for (sb_x = 0; sb_x *4 < s->fragment_width[!!plane]; sb_x++) {
1598                 vp4_dc_pred_before(s, dc_pred, sb_x);
1599                 for (j = 0; j < 16; j++) {
1600                         int hx = hilbert_offset[j][0];
1601                         int hy = hilbert_offset[j][1];
1602                         int x  = 4 * sb_x + hx;
1603                         int y  = 4 * sb_y + hy;
1604                         VP4Predictor *this_dc_pred = &dc_pred[hy + 1][hx + 1];
1605                         int fragment, dc_block_type;
1606 
1607                         if (x >= s->fragment_width[!!plane] || y >= s->fragment_height[!!plane])
1608                             continue;
1609 
1610                         fragment = s->fragment_start[plane] + y * s->fragment_width[!!plane] + x;
1611 
1612                         if (s->all_fragments[fragment].coding_method == MODE_COPY)
1613                             continue;
1614 
1615                         if (vp4_unpack_vlcs(s, gb, tables[!!plane], plane, eob_tracker, fragment) < 0)
1616                             return -1;
1617 
1618                         dc_block_type = vp4_pred_block_type_map[s->all_fragments[fragment].coding_method];
1619 
1620                         s->all_fragments[fragment].dc +=
1621                             vp4_dc_pred(s, this_dc_pred, last_dc, dc_block_type, plane);
1622 
1623                         this_dc_pred->type = dc_block_type,
1624                         this_dc_pred->dc   = last_dc[dc_block_type] = s->all_fragments[fragment].dc;
1625                 }
1626                 vp4_dc_pred_after(s, dc_pred, sb_x);
1627             }
1628         }
1629     }
1630 
1631     vp4_set_tokens_base(s);
1632 
1633     return 0;
1634 }
1635 #endif
1636 
1637 /*
1638  * This function reverses the DC prediction for each coded fragment in
1639  * the frame. Much of this function is adapted directly from the original
1640  * VP3 source code.
1641  */
1642 #define COMPATIBLE_FRAME(x)                                                   \
1643     (compatible_frame[s->all_fragments[x].coding_method] == current_frame_type)
1644 #define DC_COEFF(u) s->all_fragments[u].dc
1645 
reverse_dc_prediction(Vp3DecodeContext * s,int first_fragment,int fragment_width,int fragment_height)1646 static void reverse_dc_prediction(Vp3DecodeContext *s,
1647                                   int first_fragment,
1648                                   int fragment_width,
1649                                   int fragment_height)
1650 {
1651 #define PUL 8
1652 #define PU 4
1653 #define PUR 2
1654 #define PL 1
1655 
1656     int x, y;
1657     int i = first_fragment;
1658 
1659     int predicted_dc;
1660 
1661     /* DC values for the left, up-left, up, and up-right fragments */
1662     int vl, vul, vu, vur;
1663 
1664     /* indexes for the left, up-left, up, and up-right fragments */
1665     int l, ul, u, ur;
1666 
1667     /*
1668      * The 6 fields mean:
1669      *   0: up-left multiplier
1670      *   1: up multiplier
1671      *   2: up-right multiplier
1672      *   3: left multiplier
1673      */
1674     static const int predictor_transform[16][4] = {
1675         {    0,   0,   0,   0 },
1676         {    0,   0,   0, 128 }, // PL
1677         {    0,   0, 128,   0 }, // PUR
1678         {    0,   0,  53,  75 }, // PUR|PL
1679         {    0, 128,   0,   0 }, // PU
1680         {    0,  64,   0,  64 }, // PU |PL
1681         {    0, 128,   0,   0 }, // PU |PUR
1682         {    0,   0,  53,  75 }, // PU |PUR|PL
1683         {  128,   0,   0,   0 }, // PUL
1684         {    0,   0,   0, 128 }, // PUL|PL
1685         {   64,   0,  64,   0 }, // PUL|PUR
1686         {    0,   0,  53,  75 }, // PUL|PUR|PL
1687         {    0, 128,   0,   0 }, // PUL|PU
1688         { -104, 116,   0, 116 }, // PUL|PU |PL
1689         {   24,  80,  24,   0 }, // PUL|PU |PUR
1690         { -104, 116,   0, 116 }  // PUL|PU |PUR|PL
1691     };
1692 
1693     /* This table shows which types of blocks can use other blocks for
1694      * prediction. For example, INTRA is the only mode in this table to
1695      * have a frame number of 0. That means INTRA blocks can only predict
1696      * from other INTRA blocks. There are 2 golden frame coding types;
1697      * blocks encoding in these modes can only predict from other blocks
1698      * that were encoded with these 1 of these 2 modes. */
1699     static const unsigned char compatible_frame[9] = {
1700         1,    /* MODE_INTER_NO_MV */
1701         0,    /* MODE_INTRA */
1702         1,    /* MODE_INTER_PLUS_MV */
1703         1,    /* MODE_INTER_LAST_MV */
1704         1,    /* MODE_INTER_PRIOR_MV */
1705         2,    /* MODE_USING_GOLDEN */
1706         2,    /* MODE_GOLDEN_MV */
1707         1,    /* MODE_INTER_FOUR_MV */
1708         3     /* MODE_COPY */
1709     };
1710     int current_frame_type;
1711 
1712     /* there is a last DC predictor for each of the 3 frame types */
1713     short last_dc[3];
1714 
1715     int transform = 0;
1716 
1717     vul =
1718     vu  =
1719     vur =
1720     vl  = 0;
1721     last_dc[0] =
1722     last_dc[1] =
1723     last_dc[2] = 0;
1724 
1725     /* for each fragment row... */
1726     for (y = 0; y < fragment_height; y++) {
1727         /* for each fragment in a row... */
1728         for (x = 0; x < fragment_width; x++, i++) {
1729 
1730             /* reverse prediction if this block was coded */
1731             if (s->all_fragments[i].coding_method != MODE_COPY) {
1732                 current_frame_type =
1733                     compatible_frame[s->all_fragments[i].coding_method];
1734 
1735                 transform = 0;
1736                 if (x) {
1737                     l  = i - 1;
1738                     vl = DC_COEFF(l);
1739                     if (COMPATIBLE_FRAME(l))
1740                         transform |= PL;
1741                 }
1742                 if (y) {
1743                     u  = i - fragment_width;
1744                     vu = DC_COEFF(u);
1745                     if (COMPATIBLE_FRAME(u))
1746                         transform |= PU;
1747                     if (x) {
1748                         ul  = i - fragment_width - 1;
1749                         vul = DC_COEFF(ul);
1750                         if (COMPATIBLE_FRAME(ul))
1751                             transform |= PUL;
1752                     }
1753                     if (x + 1 < fragment_width) {
1754                         ur  = i - fragment_width + 1;
1755                         vur = DC_COEFF(ur);
1756                         if (COMPATIBLE_FRAME(ur))
1757                             transform |= PUR;
1758                     }
1759                 }
1760 
1761                 if (transform == 0) {
1762                     /* if there were no fragments to predict from, use last
1763                      * DC saved */
1764                     predicted_dc = last_dc[current_frame_type];
1765                 } else {
1766                     /* apply the appropriate predictor transform */
1767                     predicted_dc =
1768                         (predictor_transform[transform][0] * vul) +
1769                         (predictor_transform[transform][1] * vu) +
1770                         (predictor_transform[transform][2] * vur) +
1771                         (predictor_transform[transform][3] * vl);
1772 
1773                     predicted_dc /= 128;
1774 
1775                     /* check for outranging on the [ul u l] and
1776                      * [ul u ur l] predictors */
1777                     if ((transform == 15) || (transform == 13)) {
1778                         if (FFABS(predicted_dc - vu) > 128)
1779                             predicted_dc = vu;
1780                         else if (FFABS(predicted_dc - vl) > 128)
1781                             predicted_dc = vl;
1782                         else if (FFABS(predicted_dc - vul) > 128)
1783                             predicted_dc = vul;
1784                     }
1785                 }
1786 
1787                 /* at long last, apply the predictor */
1788                 DC_COEFF(i) += predicted_dc;
1789                 /* save the DC */
1790                 last_dc[current_frame_type] = DC_COEFF(i);
1791             }
1792         }
1793     }
1794 }
1795 
apply_loop_filter(Vp3DecodeContext * s,int plane,int ystart,int yend)1796 static void apply_loop_filter(Vp3DecodeContext *s, int plane,
1797                               int ystart, int yend)
1798 {
1799     int x, y;
1800     int *bounding_values = s->bounding_values_array + 127;
1801 
1802     int width           = s->fragment_width[!!plane];
1803     int height          = s->fragment_height[!!plane];
1804     int fragment        = s->fragment_start[plane] + ystart * width;
1805     ptrdiff_t stride    = s->current_frame.f->linesize[plane];
1806     uint8_t *plane_data = s->current_frame.f->data[plane];
1807     if (!s->flipped_image)
1808         stride = -stride;
1809     plane_data += s->data_offset[plane] + 8 * ystart * stride;
1810 
1811     for (y = ystart; y < yend; y++) {
1812         for (x = 0; x < width; x++) {
1813             /* This code basically just deblocks on the edges of coded blocks.
1814              * However, it has to be much more complicated because of the
1815              * brain damaged deblock ordering used in VP3/Theora. Order matters
1816              * because some pixels get filtered twice. */
1817             if (s->all_fragments[fragment].coding_method != MODE_COPY) {
1818                 /* do not perform left edge filter for left columns frags */
1819                 if (x > 0) {
1820                     s->vp3dsp.h_loop_filter(
1821                         plane_data + 8 * x,
1822                         stride, bounding_values);
1823                 }
1824 
1825                 /* do not perform top edge filter for top row fragments */
1826                 if (y > 0) {
1827                     s->vp3dsp.v_loop_filter(
1828                         plane_data + 8 * x,
1829                         stride, bounding_values);
1830                 }
1831 
1832                 /* do not perform right edge filter for right column
1833                  * fragments or if right fragment neighbor is also coded
1834                  * in this frame (it will be filtered in next iteration) */
1835                 if ((x < width - 1) &&
1836                     (s->all_fragments[fragment + 1].coding_method == MODE_COPY)) {
1837                     s->vp3dsp.h_loop_filter(
1838                         plane_data + 8 * x + 8,
1839                         stride, bounding_values);
1840                 }
1841 
1842                 /* do not perform bottom edge filter for bottom row
1843                  * fragments or if bottom fragment neighbor is also coded
1844                  * in this frame (it will be filtered in the next row) */
1845                 if ((y < height - 1) &&
1846                     (s->all_fragments[fragment + width].coding_method == MODE_COPY)) {
1847                     s->vp3dsp.v_loop_filter(
1848                         plane_data + 8 * x + 8 * stride,
1849                         stride, bounding_values);
1850                 }
1851             }
1852 
1853             fragment++;
1854         }
1855         plane_data += 8 * stride;
1856     }
1857 }
1858 
1859 /**
1860  * Pull DCT tokens from the 64 levels to decode and dequant the coefficients
1861  * for the next block in coding order
1862  */
vp3_dequant(Vp3DecodeContext * s,Vp3Fragment * frag,int plane,int inter,int16_t block[64])1863 static inline int vp3_dequant(Vp3DecodeContext *s, Vp3Fragment *frag,
1864                               int plane, int inter, int16_t block[64])
1865 {
1866     int16_t *dequantizer = s->qmat[frag->qpi][inter][plane];
1867     uint8_t *perm = s->idct_scantable;
1868     int i = 0;
1869 
1870     do {
1871         int token = *s->dct_tokens[plane][i];
1872         switch (token & 3) {
1873         case 0: // EOB
1874             if (--token < 4) // 0-3 are token types so the EOB run must now be 0
1875                 s->dct_tokens[plane][i]++;
1876             else
1877                 *s->dct_tokens[plane][i] = token & ~3;
1878             goto end;
1879         case 1: // zero run
1880             s->dct_tokens[plane][i]++;
1881             i += (token >> 2) & 0x7f;
1882             if (i > 63) {
1883                 av_log(s->avctx, AV_LOG_ERROR, "Coefficient index overflow\n");
1884                 return i;
1885             }
1886             block[perm[i]] = (token >> 9) * dequantizer[perm[i]];
1887             i++;
1888             break;
1889         case 2: // coeff
1890             block[perm[i]] = (token >> 2) * dequantizer[perm[i]];
1891             s->dct_tokens[plane][i++]++;
1892             break;
1893         default: // shouldn't happen
1894             return i;
1895         }
1896     } while (i < 64);
1897     // return value is expected to be a valid level
1898     i--;
1899 end:
1900     // the actual DC+prediction is in the fragment structure
1901     block[0] = frag->dc * s->qmat[0][inter][plane][0];
1902     return i;
1903 }
1904 
1905 /**
1906  * called when all pixels up to row y are complete
1907  */
vp3_draw_horiz_band(Vp3DecodeContext * s,int y)1908 static void vp3_draw_horiz_band(Vp3DecodeContext *s, int y)
1909 {
1910     int h, cy, i;
1911     int offset[AV_NUM_DATA_POINTERS];
1912 
1913     if (HAVE_THREADS && s->avctx->active_thread_type & FF_THREAD_FRAME) {
1914         int y_flipped = s->flipped_image ? s->height - y : y;
1915 
1916         /* At the end of the frame, report INT_MAX instead of the height of
1917          * the frame. This makes the other threads' ff_thread_await_progress()
1918          * calls cheaper, because they don't have to clip their values. */
1919         ff_thread_report_progress(&s->current_frame,
1920                                   y_flipped == s->height ? INT_MAX
1921                                                          : y_flipped - 1,
1922                                   0);
1923     }
1924 
1925     if (!s->avctx->draw_horiz_band)
1926         return;
1927 
1928     h = y - s->last_slice_end;
1929     s->last_slice_end = y;
1930     y -= h;
1931 
1932     if (!s->flipped_image)
1933         y = s->height - y - h;
1934 
1935     cy        = y >> s->chroma_y_shift;
1936     offset[0] = s->current_frame.f->linesize[0] * y;
1937     offset[1] = s->current_frame.f->linesize[1] * cy;
1938     offset[2] = s->current_frame.f->linesize[2] * cy;
1939     for (i = 3; i < AV_NUM_DATA_POINTERS; i++)
1940         offset[i] = 0;
1941 
1942     emms_c();
1943     s->avctx->draw_horiz_band(s->avctx, s->current_frame.f, offset, y, 3, h);
1944 }
1945 
1946 /**
1947  * Wait for the reference frame of the current fragment.
1948  * The progress value is in luma pixel rows.
1949  */
await_reference_row(Vp3DecodeContext * s,Vp3Fragment * fragment,int motion_y,int y)1950 static void await_reference_row(Vp3DecodeContext *s, Vp3Fragment *fragment,
1951                                 int motion_y, int y)
1952 {
1953     ThreadFrame *ref_frame;
1954     int ref_row;
1955     int border = motion_y & 1;
1956 
1957     if (fragment->coding_method == MODE_USING_GOLDEN ||
1958         fragment->coding_method == MODE_GOLDEN_MV)
1959         ref_frame = &s->golden_frame;
1960     else
1961         ref_frame = &s->last_frame;
1962 
1963     ref_row = y + (motion_y >> 1);
1964     ref_row = FFMAX(FFABS(ref_row), ref_row + 8 + border);
1965 
1966     ff_thread_await_progress(ref_frame, ref_row, 0);
1967 }
1968 
1969 #if CONFIG_VP4_DECODER
1970 /**
1971  * @return non-zero if temp (edge_emu_buffer) was populated
1972  */
vp4_mc_loop_filter(Vp3DecodeContext * s,int plane,int motion_x,int motion_y,int bx,int by,uint8_t * motion_source,int stride,int src_x,int src_y,uint8_t * temp)1973 static int vp4_mc_loop_filter(Vp3DecodeContext *s, int plane, int motion_x, int motion_y, int bx, int by,
1974        uint8_t * motion_source, int stride, int src_x, int src_y, uint8_t *temp)
1975 {
1976     int motion_shift = plane ? 4 : 2;
1977     int subpel_mask = plane ? 3 : 1;
1978     int *bounding_values = s->bounding_values_array + 127;
1979 
1980     int i;
1981     int x, y;
1982     int x2, y2;
1983     int x_subpel, y_subpel;
1984     int x_offset, y_offset;
1985 
1986     int block_width = plane ? 8 : 16;
1987     int plane_width  = s->width  >> (plane && s->chroma_x_shift);
1988     int plane_height = s->height >> (plane && s->chroma_y_shift);
1989 
1990 #define loop_stride 12
1991     uint8_t loop[12 * loop_stride];
1992 
1993     /* using division instead of shift to correctly handle negative values */
1994     x = 8 * bx + motion_x / motion_shift;
1995     y = 8 * by + motion_y / motion_shift;
1996 
1997     x_subpel = motion_x & subpel_mask;
1998     y_subpel = motion_y & subpel_mask;
1999 
2000     if (x_subpel || y_subpel) {
2001         x--;
2002         y--;
2003 
2004         if (x_subpel)
2005             x = FFMIN(x, x + FFSIGN(motion_x));
2006 
2007         if (y_subpel)
2008             y = FFMIN(y, y + FFSIGN(motion_y));
2009 
2010         x2 = x + block_width;
2011         y2 = y + block_width;
2012 
2013         if (x2 < 0 || x2 >= plane_width || y2 < 0 || y2 >= plane_height)
2014             return 0;
2015 
2016         x_offset = (-(x + 2) & 7) + 2;
2017         y_offset = (-(y + 2) & 7) + 2;
2018 
2019         if (x_offset > 8 + x_subpel && y_offset > 8 + y_subpel)
2020             return 0;
2021 
2022         s->vdsp.emulated_edge_mc(loop, motion_source - stride - 1,
2023              loop_stride, stride,
2024              12, 12, src_x - 1, src_y - 1,
2025              plane_width,
2026              plane_height);
2027 
2028         if (x_offset <= 8 + x_subpel)
2029             ff_vp3dsp_h_loop_filter_12(loop + x_offset, loop_stride, bounding_values);
2030 
2031         if (y_offset <= 8 + y_subpel)
2032             ff_vp3dsp_v_loop_filter_12(loop + y_offset*loop_stride, loop_stride, bounding_values);
2033 
2034     } else {
2035 
2036         x_offset = -x & 7;
2037         y_offset = -y & 7;
2038 
2039         if (!x_offset && !y_offset)
2040             return 0;
2041 
2042         s->vdsp.emulated_edge_mc(loop, motion_source - stride - 1,
2043              loop_stride, stride,
2044              12, 12, src_x - 1, src_y - 1,
2045              plane_width,
2046              plane_height);
2047 
2048 #define safe_loop_filter(name, ptr, stride, bounding_values) \
2049     if ((uintptr_t)(ptr) & 7) \
2050         s->vp3dsp.name##_unaligned(ptr, stride, bounding_values); \
2051     else \
2052         s->vp3dsp.name(ptr, stride, bounding_values);
2053 
2054         if (x_offset)
2055             safe_loop_filter(h_loop_filter, loop + loop_stride + x_offset + 1, loop_stride, bounding_values);
2056 
2057         if (y_offset)
2058             safe_loop_filter(v_loop_filter, loop + (y_offset + 1)*loop_stride + 1, loop_stride, bounding_values);
2059     }
2060 
2061     for (i = 0; i < 9; i++)
2062         memcpy(temp + i*stride, loop + (i + 1) * loop_stride + 1, 9);
2063 
2064     return 1;
2065 }
2066 #endif
2067 
2068 /*
2069  * Perform the final rendering for a particular slice of data.
2070  * The slice number ranges from 0..(c_superblock_height - 1).
2071  */
render_slice(Vp3DecodeContext * s,int slice)2072 static void render_slice(Vp3DecodeContext *s, int slice)
2073 {
2074     int x, y, i, j, fragment;
2075     int16_t *block = s->block;
2076     int motion_x = 0xdeadbeef, motion_y = 0xdeadbeef;
2077     int motion_halfpel_index;
2078     uint8_t *motion_source;
2079     int plane, first_pixel;
2080 
2081     if (slice >= s->c_superblock_height)
2082         return;
2083 
2084     for (plane = 0; plane < 3; plane++) {
2085         uint8_t *output_plane = s->current_frame.f->data[plane] +
2086                                 s->data_offset[plane];
2087         uint8_t *last_plane = s->last_frame.f->data[plane] +
2088                               s->data_offset[plane];
2089         uint8_t *golden_plane = s->golden_frame.f->data[plane] +
2090                                 s->data_offset[plane];
2091         ptrdiff_t stride = s->current_frame.f->linesize[plane];
2092         int plane_width  = s->width  >> (plane && s->chroma_x_shift);
2093         int plane_height = s->height >> (plane && s->chroma_y_shift);
2094         int8_t(*motion_val)[2] = s->motion_val[!!plane];
2095 
2096         int sb_x, sb_y = slice << (!plane && s->chroma_y_shift);
2097         int slice_height = sb_y + 1 + (!plane && s->chroma_y_shift);
2098         int slice_width  = plane ? s->c_superblock_width
2099                                  : s->y_superblock_width;
2100 
2101         int fragment_width  = s->fragment_width[!!plane];
2102         int fragment_height = s->fragment_height[!!plane];
2103         int fragment_start  = s->fragment_start[plane];
2104 
2105         int do_await = !plane && HAVE_THREADS &&
2106                        (s->avctx->active_thread_type & FF_THREAD_FRAME);
2107 
2108         if (!s->flipped_image)
2109             stride = -stride;
2110         if (CONFIG_GRAY && plane && (s->avctx->flags & AV_CODEC_FLAG_GRAY))
2111             continue;
2112 
2113         /* for each superblock row in the slice (both of them)... */
2114         for (; sb_y < slice_height; sb_y++) {
2115             /* for each superblock in a row... */
2116             for (sb_x = 0; sb_x < slice_width; sb_x++) {
2117                 /* for each block in a superblock... */
2118                 for (j = 0; j < 16; j++) {
2119                     x        = 4 * sb_x + hilbert_offset[j][0];
2120                     y        = 4 * sb_y + hilbert_offset[j][1];
2121                     fragment = y * fragment_width + x;
2122 
2123                     i = fragment_start + fragment;
2124 
2125                     // bounds check
2126                     if (x >= fragment_width || y >= fragment_height)
2127                         continue;
2128 
2129                     first_pixel = 8 * y * stride + 8 * x;
2130 
2131                     if (do_await &&
2132                         s->all_fragments[i].coding_method != MODE_INTRA)
2133                         await_reference_row(s, &s->all_fragments[i],
2134                                             motion_val[fragment][1],
2135                                             (16 * y) >> s->chroma_y_shift);
2136 
2137                     /* transform if this block was coded */
2138                     if (s->all_fragments[i].coding_method != MODE_COPY) {
2139                         if ((s->all_fragments[i].coding_method == MODE_USING_GOLDEN) ||
2140                             (s->all_fragments[i].coding_method == MODE_GOLDEN_MV))
2141                             motion_source = golden_plane;
2142                         else
2143                             motion_source = last_plane;
2144 
2145                         motion_source       += first_pixel;
2146                         motion_halfpel_index = 0;
2147 
2148                         /* sort out the motion vector if this fragment is coded
2149                          * using a motion vector method */
2150                         if ((s->all_fragments[i].coding_method > MODE_INTRA) &&
2151                             (s->all_fragments[i].coding_method != MODE_USING_GOLDEN)) {
2152                             int src_x, src_y;
2153                             int standard_mc = 1;
2154                             motion_x = motion_val[fragment][0];
2155                             motion_y = motion_val[fragment][1];
2156 #if CONFIG_VP4_DECODER
2157                             if (plane && s->version >= 2) {
2158                                 motion_x = (motion_x >> 1) | (motion_x & 1);
2159                                 motion_y = (motion_y >> 1) | (motion_y & 1);
2160                             }
2161 #endif
2162 
2163                             src_x = (motion_x >> 1) + 8 * x;
2164                             src_y = (motion_y >> 1) + 8 * y;
2165 
2166                             motion_halfpel_index = motion_x & 0x01;
2167                             motion_source       += (motion_x >> 1);
2168 
2169                             motion_halfpel_index |= (motion_y & 0x01) << 1;
2170                             motion_source        += ((motion_y >> 1) * stride);
2171 
2172 #if CONFIG_VP4_DECODER
2173                             if (s->version >= 2) {
2174                                 uint8_t *temp = s->edge_emu_buffer;
2175                                 if (stride < 0)
2176                                     temp -= 8 * stride;
2177                                 if (vp4_mc_loop_filter(s, plane, motion_val[fragment][0], motion_val[fragment][1], x, y, motion_source, stride, src_x, src_y, temp)) {
2178                                     motion_source = temp;
2179                                     standard_mc = 0;
2180                                 }
2181                             }
2182 #endif
2183 
2184                             if (standard_mc && (
2185                                 src_x < 0 || src_y < 0 ||
2186                                 src_x + 9 >= plane_width ||
2187                                 src_y + 9 >= plane_height)) {
2188                                 uint8_t *temp = s->edge_emu_buffer;
2189                                 if (stride < 0)
2190                                     temp -= 8 * stride;
2191 
2192                                 s->vdsp.emulated_edge_mc(temp, motion_source,
2193                                                          stride, stride,
2194                                                          9, 9, src_x, src_y,
2195                                                          plane_width,
2196                                                          plane_height);
2197                                 motion_source = temp;
2198                             }
2199                         }
2200 
2201                         /* first, take care of copying a block from either the
2202                          * previous or the golden frame */
2203                         if (s->all_fragments[i].coding_method != MODE_INTRA) {
2204                             /* Note, it is possible to implement all MC cases
2205                              * with put_no_rnd_pixels_l2 which would look more
2206                              * like the VP3 source but this would be slower as
2207                              * put_no_rnd_pixels_tab is better optimized */
2208                             if (motion_halfpel_index != 3) {
2209                                 s->hdsp.put_no_rnd_pixels_tab[1][motion_halfpel_index](
2210                                     output_plane + first_pixel,
2211                                     motion_source, stride, 8);
2212                             } else {
2213                                 /* d is 0 if motion_x and _y have the same sign,
2214                                  * else -1 */
2215                                 int d = (motion_x ^ motion_y) >> 31;
2216                                 s->vp3dsp.put_no_rnd_pixels_l2(output_plane + first_pixel,
2217                                                                motion_source - d,
2218                                                                motion_source + stride + 1 + d,
2219                                                                stride, 8);
2220                             }
2221                         }
2222 
2223                         /* invert DCT and place (or add) in final output */
2224 
2225                         if (s->all_fragments[i].coding_method == MODE_INTRA) {
2226                             vp3_dequant(s, s->all_fragments + i,
2227                                         plane, 0, block);
2228                             s->vp3dsp.idct_put(output_plane + first_pixel,
2229                                                stride,
2230                                                block);
2231                         } else {
2232                             if (vp3_dequant(s, s->all_fragments + i,
2233                                             plane, 1, block)) {
2234                                 s->vp3dsp.idct_add(output_plane + first_pixel,
2235                                                    stride,
2236                                                    block);
2237                             } else {
2238                                 s->vp3dsp.idct_dc_add(output_plane + first_pixel,
2239                                                       stride, block);
2240                             }
2241                         }
2242                     } else {
2243                         /* copy directly from the previous frame */
2244                         s->hdsp.put_pixels_tab[1][0](
2245                             output_plane + first_pixel,
2246                             last_plane + first_pixel,
2247                             stride, 8);
2248                     }
2249                 }
2250             }
2251 
2252             // Filter up to the last row in the superblock row
2253             if (s->version < 2 && !s->skip_loop_filter)
2254                 apply_loop_filter(s, plane, 4 * sb_y - !!sb_y,
2255                                   FFMIN(4 * sb_y + 3, fragment_height - 1));
2256         }
2257     }
2258 
2259     /* this looks like a good place for slice dispatch... */
2260     /* algorithm:
2261      *   if (slice == s->macroblock_height - 1)
2262      *     dispatch (both last slice & 2nd-to-last slice);
2263      *   else if (slice > 0)
2264      *     dispatch (slice - 1);
2265      */
2266 
2267     vp3_draw_horiz_band(s, FFMIN((32 << s->chroma_y_shift) * (slice + 1) - 16,
2268                                  s->height - 16));
2269 }
2270 
2271 /// Allocate tables for per-frame data in Vp3DecodeContext
allocate_tables(AVCodecContext * avctx)2272 static av_cold int allocate_tables(AVCodecContext *avctx)
2273 {
2274     Vp3DecodeContext *s = avctx->priv_data;
2275     int y_fragment_count, c_fragment_count;
2276 
2277     free_tables(avctx);
2278 
2279     y_fragment_count = s->fragment_width[0] * s->fragment_height[0];
2280     c_fragment_count = s->fragment_width[1] * s->fragment_height[1];
2281 
2282     /* superblock_coding is used by unpack_superblocks (VP3/Theora) and vp4_unpack_macroblocks (VP4) */
2283     s->superblock_coding = av_mallocz(FFMAX(s->superblock_count, s->yuv_macroblock_count));
2284     s->all_fragments     = av_calloc(s->fragment_count, sizeof(*s->all_fragments));
2285 
2286     s-> kf_coded_fragment_list = av_calloc(s->fragment_count, sizeof(int));
2287     s->nkf_coded_fragment_list = av_calloc(s->fragment_count, sizeof(int));
2288     memset(s-> num_kf_coded_fragment, -1, sizeof(s-> num_kf_coded_fragment));
2289 
2290     s->dct_tokens_base = av_calloc(s->fragment_count,
2291                                    64 * sizeof(*s->dct_tokens_base));
2292     s->motion_val[0] = av_calloc(y_fragment_count, sizeof(*s->motion_val[0]));
2293     s->motion_val[1] = av_calloc(c_fragment_count, sizeof(*s->motion_val[1]));
2294 
2295     /* work out the block mapping tables */
2296     s->superblock_fragments = av_calloc(s->superblock_count, 16 * sizeof(int));
2297     s->macroblock_coding    = av_mallocz(s->macroblock_count + 1);
2298 
2299     s->dc_pred_row = av_malloc_array(s->y_superblock_width * 4, sizeof(*s->dc_pred_row));
2300 
2301     if (!s->superblock_coding    || !s->all_fragments          ||
2302         !s->dct_tokens_base      || !s->kf_coded_fragment_list ||
2303         !s->nkf_coded_fragment_list ||
2304         !s->superblock_fragments || !s->macroblock_coding      ||
2305         !s->dc_pred_row ||
2306         !s->motion_val[0]        || !s->motion_val[1]) {
2307         return -1;
2308     }
2309 
2310     init_block_mapping(s);
2311 
2312     return 0;
2313 }
2314 
init_frames(Vp3DecodeContext * s)2315 static av_cold int init_frames(Vp3DecodeContext *s)
2316 {
2317     s->current_frame.f = av_frame_alloc();
2318     s->last_frame.f    = av_frame_alloc();
2319     s->golden_frame.f  = av_frame_alloc();
2320 
2321     if (!s->current_frame.f || !s->last_frame.f || !s->golden_frame.f)
2322         return AVERROR(ENOMEM);
2323 
2324     return 0;
2325 }
2326 
vp3_decode_init(AVCodecContext * avctx)2327 static av_cold int vp3_decode_init(AVCodecContext *avctx)
2328 {
2329     Vp3DecodeContext *s = avctx->priv_data;
2330     int i, inter, plane, ret;
2331     int c_width;
2332     int c_height;
2333     int y_fragment_count, c_fragment_count;
2334 #if CONFIG_VP4_DECODER
2335     int j;
2336 #endif
2337 
2338     ret = init_frames(s);
2339     if (ret < 0)
2340         return ret;
2341 
2342     if (avctx->codec_tag == MKTAG('V', 'P', '4', '0')) {
2343         s->version = 3;
2344 #if !CONFIG_VP4_DECODER
2345         av_log(avctx, AV_LOG_ERROR, "This build does not support decoding VP4.\n");
2346         return AVERROR_DECODER_NOT_FOUND;
2347 #endif
2348     } else if (avctx->codec_tag == MKTAG('V', 'P', '3', '0'))
2349         s->version = 0;
2350     else
2351         s->version = 1;
2352 
2353     s->avctx  = avctx;
2354     s->width  = FFALIGN(avctx->coded_width, 16);
2355     s->height = FFALIGN(avctx->coded_height, 16);
2356     if (s->width < 18)
2357         return AVERROR_PATCHWELCOME;
2358     if (avctx->codec_id != AV_CODEC_ID_THEORA)
2359         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
2360     avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
2361     ff_hpeldsp_init(&s->hdsp, avctx->flags | AV_CODEC_FLAG_BITEXACT);
2362     ff_videodsp_init(&s->vdsp, 8);
2363     ff_vp3dsp_init(&s->vp3dsp, avctx->flags);
2364 
2365     for (i = 0; i < 64; i++) {
2366 #define TRANSPOSE(x) (((x) >> 3) | (((x) & 7) << 3))
2367         s->idct_permutation[i] = TRANSPOSE(i);
2368         s->idct_scantable[i]   = TRANSPOSE(ff_zigzag_direct[i]);
2369 #undef TRANSPOSE
2370     }
2371 
2372     /* initialize to an impossible value which will force a recalculation
2373      * in the first frame decode */
2374     for (i = 0; i < 3; i++)
2375         s->qps[i] = -1;
2376 
2377     ret = av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &s->chroma_x_shift, &s->chroma_y_shift);
2378     if (ret)
2379         return ret;
2380 
2381     s->y_superblock_width  = (s->width  + 31) / 32;
2382     s->y_superblock_height = (s->height + 31) / 32;
2383     s->y_superblock_count  = s->y_superblock_width * s->y_superblock_height;
2384 
2385     /* work out the dimensions for the C planes */
2386     c_width                = s->width >> s->chroma_x_shift;
2387     c_height               = s->height >> s->chroma_y_shift;
2388     s->c_superblock_width  = (c_width  + 31) / 32;
2389     s->c_superblock_height = (c_height + 31) / 32;
2390     s->c_superblock_count  = s->c_superblock_width * s->c_superblock_height;
2391 
2392     s->superblock_count   = s->y_superblock_count + (s->c_superblock_count * 2);
2393     s->u_superblock_start = s->y_superblock_count;
2394     s->v_superblock_start = s->u_superblock_start + s->c_superblock_count;
2395 
2396     s->macroblock_width  = (s->width  + 15) / 16;
2397     s->macroblock_height = (s->height + 15) / 16;
2398     s->macroblock_count  = s->macroblock_width * s->macroblock_height;
2399     s->c_macroblock_width  = (c_width  + 15) / 16;
2400     s->c_macroblock_height = (c_height + 15) / 16;
2401     s->c_macroblock_count  = s->c_macroblock_width * s->c_macroblock_height;
2402     s->yuv_macroblock_count = s->macroblock_count + 2 * s->c_macroblock_count;
2403 
2404     s->fragment_width[0]  = s->width / FRAGMENT_PIXELS;
2405     s->fragment_height[0] = s->height / FRAGMENT_PIXELS;
2406     s->fragment_width[1]  = s->fragment_width[0] >> s->chroma_x_shift;
2407     s->fragment_height[1] = s->fragment_height[0] >> s->chroma_y_shift;
2408 
2409     /* fragment count covers all 8x8 blocks for all 3 planes */
2410     y_fragment_count     = s->fragment_width[0] * s->fragment_height[0];
2411     c_fragment_count     = s->fragment_width[1] * s->fragment_height[1];
2412     s->fragment_count    = y_fragment_count + 2 * c_fragment_count;
2413     s->fragment_start[1] = y_fragment_count;
2414     s->fragment_start[2] = y_fragment_count + c_fragment_count;
2415 
2416     if (!s->theora_tables) {
2417         const uint8_t (*bias_tabs)[32][2];
2418 
2419         for (i = 0; i < 64; i++) {
2420             s->coded_dc_scale_factor[0][i] = s->version < 2 ? vp31_dc_scale_factor[i] : vp4_y_dc_scale_factor[i];
2421             s->coded_dc_scale_factor[1][i] = s->version < 2 ? vp31_dc_scale_factor[i] : vp4_uv_dc_scale_factor[i];
2422             s->coded_ac_scale_factor[i] = s->version < 2 ? vp31_ac_scale_factor[i] : vp4_ac_scale_factor[i];
2423             s->base_matrix[0][i]        = s->version < 2 ? vp31_intra_y_dequant[i] : vp4_generic_dequant[i];
2424             s->base_matrix[1][i]        = s->version < 2 ? vp31_intra_c_dequant[i] : vp4_generic_dequant[i];
2425             s->base_matrix[2][i]        = s->version < 2 ? vp31_inter_dequant[i]   : vp4_generic_dequant[i];
2426             s->filter_limit_values[i]   = s->version < 2 ? vp31_filter_limit_values[i] : vp4_filter_limit_values[i];
2427         }
2428 
2429         for (inter = 0; inter < 2; inter++) {
2430             for (plane = 0; plane < 3; plane++) {
2431                 s->qr_count[inter][plane]   = 1;
2432                 s->qr_size[inter][plane][0] = 63;
2433                 s->qr_base[inter][plane][0] =
2434                 s->qr_base[inter][plane][1] = 2 * inter + (!!plane) * !inter;
2435             }
2436         }
2437 
2438         /* init VLC tables */
2439         bias_tabs = CONFIG_VP4_DECODER && s->version >= 2 ? vp4_bias : vp3_bias;
2440         for (int i = 0; i < FF_ARRAY_ELEMS(s->coeff_vlc); i++) {
2441             ret = ff_init_vlc_from_lengths(&s->coeff_vlc[i], 11, 32,
2442                                            &bias_tabs[i][0][1], 2,
2443                                            &bias_tabs[i][0][0], 2, 1,
2444                                            0, 0, avctx);
2445             if (ret < 0)
2446                 return ret;
2447         }
2448     } else {
2449         for (i = 0; i < FF_ARRAY_ELEMS(s->coeff_vlc); i++) {
2450             const HuffTable *tab = &s->huffman_table[i];
2451 
2452             ret = ff_init_vlc_from_lengths(&s->coeff_vlc[i], 11, tab->nb_entries,
2453                                            &tab->entries[0].len, sizeof(*tab->entries),
2454                                            &tab->entries[0].sym, sizeof(*tab->entries), 1,
2455                                            0, 0, avctx);
2456             if (ret < 0)
2457                 return ret;
2458         }
2459     }
2460 
2461     ret = ff_init_vlc_from_lengths(&s->superblock_run_length_vlc, SUPERBLOCK_VLC_BITS, 34,
2462                                    superblock_run_length_vlc_lens, 1,
2463                                    NULL, 0, 0, 1, 0, avctx);
2464     if (ret < 0)
2465         return ret;
2466 
2467     ret = ff_init_vlc_from_lengths(&s->fragment_run_length_vlc, 5, 30,
2468                                    fragment_run_length_vlc_len, 1,
2469                                    NULL, 0, 0, 0, 0, avctx);
2470     if (ret < 0)
2471         return ret;
2472 
2473     ret = ff_init_vlc_from_lengths(&s->mode_code_vlc, 3, 8,
2474                                    mode_code_vlc_len, 1,
2475                                    NULL, 0, 0, 0, 0, avctx);
2476     if (ret < 0)
2477         return ret;
2478 
2479     ret = ff_init_vlc_from_lengths(&s->motion_vector_vlc, VP3_MV_VLC_BITS, 63,
2480                                    &motion_vector_vlc_table[0][1], 2,
2481                                    &motion_vector_vlc_table[0][0], 2, 1,
2482                                    -31, 0, avctx);
2483     if (ret < 0)
2484         return ret;
2485 
2486 #if CONFIG_VP4_DECODER
2487     for (j = 0; j < 2; j++)
2488         for (i = 0; i < 7; i++) {
2489             ret = ff_init_vlc_from_lengths(&s->vp4_mv_vlc[j][i], VP4_MV_VLC_BITS, 63,
2490                                            &vp4_mv_vlc[j][i][0][1], 2,
2491                                            &vp4_mv_vlc[j][i][0][0], 2, 1, -31,
2492                                            0, avctx);
2493             if (ret < 0)
2494                 return ret;
2495         }
2496 
2497     /* version >= 2 */
2498     for (i = 0; i < 2; i++)
2499         if ((ret = init_vlc(&s->block_pattern_vlc[i], 3, 14,
2500                             &vp4_block_pattern_vlc[i][0][1], 2, 1,
2501                             &vp4_block_pattern_vlc[i][0][0], 2, 1, 0)) < 0)
2502             return ret;
2503 #endif
2504 
2505     return allocate_tables(avctx);
2506 }
2507 
2508 /// Release and shuffle frames after decode finishes
update_frames(AVCodecContext * avctx)2509 static int update_frames(AVCodecContext *avctx)
2510 {
2511     Vp3DecodeContext *s = avctx->priv_data;
2512     int ret = 0;
2513 
2514     /* shuffle frames (last = current) */
2515     ff_thread_release_ext_buffer(avctx, &s->last_frame);
2516     ret = ff_thread_ref_frame(&s->last_frame, &s->current_frame);
2517     if (ret < 0)
2518         goto fail;
2519 
2520     if (s->keyframe) {
2521         ff_thread_release_ext_buffer(avctx, &s->golden_frame);
2522         ret = ff_thread_ref_frame(&s->golden_frame, &s->current_frame);
2523     }
2524 
2525 fail:
2526     ff_thread_release_ext_buffer(avctx, &s->current_frame);
2527     return ret;
2528 }
2529 
2530 #if HAVE_THREADS
ref_frame(Vp3DecodeContext * s,ThreadFrame * dst,ThreadFrame * src)2531 static int ref_frame(Vp3DecodeContext *s, ThreadFrame *dst, ThreadFrame *src)
2532 {
2533     ff_thread_release_ext_buffer(s->avctx, dst);
2534     if (src->f->data[0])
2535         return ff_thread_ref_frame(dst, src);
2536     return 0;
2537 }
2538 
ref_frames(Vp3DecodeContext * dst,Vp3DecodeContext * src)2539 static int ref_frames(Vp3DecodeContext *dst, Vp3DecodeContext *src)
2540 {
2541     int ret;
2542     if ((ret = ref_frame(dst, &dst->current_frame, &src->current_frame)) < 0 ||
2543         (ret = ref_frame(dst, &dst->golden_frame,  &src->golden_frame)) < 0  ||
2544         (ret = ref_frame(dst, &dst->last_frame,    &src->last_frame)) < 0)
2545         return ret;
2546     return 0;
2547 }
2548 
vp3_update_thread_context(AVCodecContext * dst,const AVCodecContext * src)2549 static int vp3_update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
2550 {
2551     Vp3DecodeContext *s = dst->priv_data, *s1 = src->priv_data;
2552     int qps_changed = 0, i, err;
2553 
2554     if (!s1->current_frame.f->data[0] ||
2555         s->width != s1->width || s->height != s1->height) {
2556         if (s != s1)
2557             ref_frames(s, s1);
2558         return -1;
2559     }
2560 
2561     if (s != s1) {
2562         // copy previous frame data
2563         if ((err = ref_frames(s, s1)) < 0)
2564             return err;
2565 
2566         s->keyframe = s1->keyframe;
2567 
2568         // copy qscale data if necessary
2569         for (i = 0; i < 3; i++) {
2570             if (s->qps[i] != s1->qps[1]) {
2571                 qps_changed = 1;
2572                 memcpy(&s->qmat[i], &s1->qmat[i], sizeof(s->qmat[i]));
2573             }
2574         }
2575 
2576         if (s->qps[0] != s1->qps[0])
2577             memcpy(&s->bounding_values_array, &s1->bounding_values_array,
2578                    sizeof(s->bounding_values_array));
2579 
2580         if (qps_changed) {
2581             memcpy(s->qps,      s1->qps,      sizeof(s->qps));
2582             memcpy(s->last_qps, s1->last_qps, sizeof(s->last_qps));
2583             s->nqps = s1->nqps;
2584         }
2585     }
2586 
2587     return update_frames(dst);
2588 }
2589 #endif
2590 
vp3_decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame,AVPacket * avpkt)2591 static int vp3_decode_frame(AVCodecContext *avctx, AVFrame *frame,
2592                             int *got_frame, AVPacket *avpkt)
2593 {
2594     const uint8_t *buf  = avpkt->data;
2595     int buf_size        = avpkt->size;
2596     Vp3DecodeContext *s = avctx->priv_data;
2597     GetBitContext gb;
2598     int i, ret;
2599 
2600     if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
2601         return ret;
2602 
2603 #if CONFIG_THEORA_DECODER
2604     if (s->theora && get_bits1(&gb)) {
2605         int type = get_bits(&gb, 7);
2606         skip_bits_long(&gb, 6*8); /* "theora" */
2607 
2608         if (s->avctx->active_thread_type&FF_THREAD_FRAME) {
2609             av_log(avctx, AV_LOG_ERROR, "midstream reconfiguration with multithreading is unsupported, try -threads 1\n");
2610             return AVERROR_PATCHWELCOME;
2611         }
2612         if (type == 0) {
2613             vp3_decode_end(avctx);
2614             ret = theora_decode_header(avctx, &gb);
2615 
2616             if (ret >= 0)
2617                 ret = vp3_decode_init(avctx);
2618             if (ret < 0) {
2619                 vp3_decode_end(avctx);
2620                 return ret;
2621             }
2622             return buf_size;
2623         } else if (type == 2) {
2624             vp3_decode_end(avctx);
2625             ret = theora_decode_tables(avctx, &gb);
2626             if (ret >= 0)
2627                 ret = vp3_decode_init(avctx);
2628             if (ret < 0) {
2629                 vp3_decode_end(avctx);
2630                 return ret;
2631             }
2632             return buf_size;
2633         }
2634 
2635         av_log(avctx, AV_LOG_ERROR,
2636                "Header packet passed to frame decoder, skipping\n");
2637         return -1;
2638     }
2639 #endif
2640 
2641     s->keyframe = !get_bits1(&gb);
2642     if (!s->all_fragments) {
2643         av_log(avctx, AV_LOG_ERROR, "Data packet without prior valid headers\n");
2644         return -1;
2645     }
2646     if (!s->theora)
2647         skip_bits(&gb, 1);
2648     for (i = 0; i < 3; i++)
2649         s->last_qps[i] = s->qps[i];
2650 
2651     s->nqps = 0;
2652     do {
2653         s->qps[s->nqps++] = get_bits(&gb, 6);
2654     } while (s->theora >= 0x030200 && s->nqps < 3 && get_bits1(&gb));
2655     for (i = s->nqps; i < 3; i++)
2656         s->qps[i] = -1;
2657 
2658     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2659         av_log(s->avctx, AV_LOG_INFO, " VP3 %sframe #%d: Q index = %d\n",
2660                s->keyframe ? "key" : "", avctx->frame_number + 1, s->qps[0]);
2661 
2662     s->skip_loop_filter = !s->filter_limit_values[s->qps[0]] ||
2663                           avctx->skip_loop_filter >= (s->keyframe ? AVDISCARD_ALL
2664                                                                   : AVDISCARD_NONKEY);
2665 
2666     if (s->qps[0] != s->last_qps[0])
2667         init_loop_filter(s);
2668 
2669     for (i = 0; i < s->nqps; i++)
2670         // reinit all dequantizers if the first one changed, because
2671         // the DC of the first quantizer must be used for all matrices
2672         if (s->qps[i] != s->last_qps[i] || s->qps[0] != s->last_qps[0])
2673             init_dequantizer(s, i);
2674 
2675     if (avctx->skip_frame >= AVDISCARD_NONKEY && !s->keyframe)
2676         return buf_size;
2677 
2678     s->current_frame.f->pict_type = s->keyframe ? AV_PICTURE_TYPE_I
2679                                                 : AV_PICTURE_TYPE_P;
2680     s->current_frame.f->key_frame = s->keyframe;
2681     if ((ret = ff_thread_get_ext_buffer(avctx, &s->current_frame,
2682                                         AV_GET_BUFFER_FLAG_REF)) < 0)
2683         goto error;
2684 
2685     if (!s->edge_emu_buffer) {
2686         s->edge_emu_buffer = av_malloc(9 * FFABS(s->current_frame.f->linesize[0]));
2687         if (!s->edge_emu_buffer) {
2688             ret = AVERROR(ENOMEM);
2689             goto error;
2690         }
2691     }
2692 
2693     if (s->keyframe) {
2694         if (!s->theora) {
2695             skip_bits(&gb, 4); /* width code */
2696             skip_bits(&gb, 4); /* height code */
2697             if (s->version) {
2698                 int version = get_bits(&gb, 5);
2699 #if !CONFIG_VP4_DECODER
2700                 if (version >= 2) {
2701                     av_log(avctx, AV_LOG_ERROR, "This build does not support decoding VP4.\n");
2702                     return AVERROR_DECODER_NOT_FOUND;
2703                 }
2704 #endif
2705                 s->version = version;
2706                 if (avctx->frame_number == 0)
2707                     av_log(s->avctx, AV_LOG_DEBUG,
2708                            "VP version: %d\n", s->version);
2709             }
2710         }
2711         if (s->version || s->theora) {
2712             if (get_bits1(&gb))
2713                 av_log(s->avctx, AV_LOG_ERROR,
2714                        "Warning, unsupported keyframe coding type?!\n");
2715             skip_bits(&gb, 2); /* reserved? */
2716 
2717 #if CONFIG_VP4_DECODER
2718             if (s->version >= 2) {
2719                 int mb_height, mb_width;
2720                 int mb_width_mul, mb_width_div, mb_height_mul, mb_height_div;
2721 
2722                 mb_height = get_bits(&gb, 8);
2723                 mb_width  = get_bits(&gb, 8);
2724                 if (mb_height != s->macroblock_height ||
2725                     mb_width != s->macroblock_width)
2726                     avpriv_request_sample(s->avctx, "macroblock dimension mismatch");
2727 
2728                 mb_width_mul = get_bits(&gb, 5);
2729                 mb_width_div = get_bits(&gb, 3);
2730                 mb_height_mul = get_bits(&gb, 5);
2731                 mb_height_div = get_bits(&gb, 3);
2732                 if (mb_width_mul != 1 || mb_width_div != 1 || mb_height_mul != 1 || mb_height_div != 1)
2733                     avpriv_request_sample(s->avctx, "unexpected macroblock dimension multipler/divider");
2734 
2735                 if (get_bits(&gb, 2))
2736                     avpriv_request_sample(s->avctx, "unknown bits");
2737             }
2738 #endif
2739         }
2740     } else {
2741         if (!s->golden_frame.f->data[0]) {
2742             av_log(s->avctx, AV_LOG_WARNING,
2743                    "vp3: first frame not a keyframe\n");
2744 
2745             s->golden_frame.f->pict_type = AV_PICTURE_TYPE_I;
2746             if ((ret = ff_thread_get_ext_buffer(avctx, &s->golden_frame,
2747                                                 AV_GET_BUFFER_FLAG_REF)) < 0)
2748                 goto error;
2749             ff_thread_release_ext_buffer(avctx, &s->last_frame);
2750             if ((ret = ff_thread_ref_frame(&s->last_frame,
2751                                            &s->golden_frame)) < 0)
2752                 goto error;
2753             ff_thread_report_progress(&s->last_frame, INT_MAX, 0);
2754         }
2755     }
2756 
2757     memset(s->all_fragments, 0, s->fragment_count * sizeof(Vp3Fragment));
2758     ff_thread_finish_setup(avctx);
2759 
2760     if (s->version < 2) {
2761         if ((ret = unpack_superblocks(s, &gb)) < 0) {
2762             av_log(s->avctx, AV_LOG_ERROR, "error in unpack_superblocks\n");
2763             goto error;
2764         }
2765 #if CONFIG_VP4_DECODER
2766     } else {
2767         if ((ret = vp4_unpack_macroblocks(s, &gb)) < 0) {
2768             av_log(s->avctx, AV_LOG_ERROR, "error in vp4_unpack_macroblocks\n");
2769             goto error;
2770     }
2771 #endif
2772     }
2773     if ((ret = unpack_modes(s, &gb)) < 0) {
2774         av_log(s->avctx, AV_LOG_ERROR, "error in unpack_modes\n");
2775         goto error;
2776     }
2777     if (ret = unpack_vectors(s, &gb)) {
2778         av_log(s->avctx, AV_LOG_ERROR, "error in unpack_vectors\n");
2779         goto error;
2780     }
2781     if ((ret = unpack_block_qpis(s, &gb)) < 0) {
2782         av_log(s->avctx, AV_LOG_ERROR, "error in unpack_block_qpis\n");
2783         goto error;
2784     }
2785 
2786     if (s->version < 2) {
2787         if ((ret = unpack_dct_coeffs(s, &gb)) < 0) {
2788             av_log(s->avctx, AV_LOG_ERROR, "error in unpack_dct_coeffs\n");
2789             goto error;
2790         }
2791 #if CONFIG_VP4_DECODER
2792     } else {
2793         if ((ret = vp4_unpack_dct_coeffs(s, &gb)) < 0) {
2794             av_log(s->avctx, AV_LOG_ERROR, "error in vp4_unpack_dct_coeffs\n");
2795             goto error;
2796         }
2797 #endif
2798     }
2799 
2800     for (i = 0; i < 3; i++) {
2801         int height = s->height >> (i && s->chroma_y_shift);
2802         if (s->flipped_image)
2803             s->data_offset[i] = 0;
2804         else
2805             s->data_offset[i] = (height - 1) * s->current_frame.f->linesize[i];
2806     }
2807 
2808     s->last_slice_end = 0;
2809     for (i = 0; i < s->c_superblock_height; i++)
2810         render_slice(s, i);
2811 
2812     // filter the last row
2813     if (s->version < 2)
2814         for (i = 0; i < 3; i++) {
2815             int row = (s->height >> (3 + (i && s->chroma_y_shift))) - 1;
2816             apply_loop_filter(s, i, row, row + 1);
2817         }
2818     vp3_draw_horiz_band(s, s->height);
2819 
2820     /* output frame, offset as needed */
2821     if ((ret = av_frame_ref(frame, s->current_frame.f)) < 0)
2822         return ret;
2823 
2824     frame->crop_left   = s->offset_x;
2825     frame->crop_right  = avctx->coded_width - avctx->width - s->offset_x;
2826     frame->crop_top    = s->offset_y;
2827     frame->crop_bottom = avctx->coded_height - avctx->height - s->offset_y;
2828 
2829     *got_frame = 1;
2830 
2831     if (!HAVE_THREADS || !(s->avctx->active_thread_type & FF_THREAD_FRAME)) {
2832         ret = update_frames(avctx);
2833         if (ret < 0)
2834             return ret;
2835     }
2836 
2837     return buf_size;
2838 
2839 error:
2840     ff_thread_report_progress(&s->current_frame, INT_MAX, 0);
2841 
2842     if (!HAVE_THREADS || !(s->avctx->active_thread_type & FF_THREAD_FRAME))
2843         av_frame_unref(s->current_frame.f);
2844 
2845     return ret;
2846 }
2847 
read_huffman_tree(HuffTable * huff,GetBitContext * gb,int length,AVCodecContext * avctx)2848 static int read_huffman_tree(HuffTable *huff, GetBitContext *gb, int length,
2849                              AVCodecContext *avctx)
2850 {
2851     if (get_bits1(gb)) {
2852         int token;
2853         if (huff->nb_entries >= 32) { /* overflow */
2854             av_log(avctx, AV_LOG_ERROR, "huffman tree overflow\n");
2855             return -1;
2856         }
2857         token = get_bits(gb, 5);
2858         ff_dlog(avctx, "code length %d, curr entry %d, token %d\n",
2859                 length, huff->nb_entries, token);
2860         huff->entries[huff->nb_entries++] = (HuffEntry){ length, token };
2861     } else {
2862         /* The following bound follows from the fact that nb_entries <= 32. */
2863         if (length >= 31) { /* overflow */
2864             av_log(avctx, AV_LOG_ERROR, "huffman tree overflow\n");
2865             return -1;
2866         }
2867         length++;
2868         if (read_huffman_tree(huff, gb, length, avctx))
2869             return -1;
2870         if (read_huffman_tree(huff, gb, length, avctx))
2871             return -1;
2872     }
2873     return 0;
2874 }
2875 
2876 #if CONFIG_THEORA_DECODER
2877 static const enum AVPixelFormat theora_pix_fmts[4] = {
2878     AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P
2879 };
2880 
theora_decode_header(AVCodecContext * avctx,GetBitContext * gb)2881 static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb)
2882 {
2883     Vp3DecodeContext *s = avctx->priv_data;
2884     int visible_width, visible_height, colorspace;
2885     uint8_t offset_x = 0, offset_y = 0;
2886     int ret;
2887     AVRational fps, aspect;
2888 
2889     if (get_bits_left(gb) < 206)
2890         return AVERROR_INVALIDDATA;
2891 
2892     s->theora_header = 0;
2893     s->theora = get_bits(gb, 24);
2894     av_log(avctx, AV_LOG_DEBUG, "Theora bitstream version %X\n", s->theora);
2895     if (!s->theora) {
2896         s->theora = 1;
2897         avpriv_request_sample(s->avctx, "theora 0");
2898     }
2899 
2900     /* 3.2.0 aka alpha3 has the same frame orientation as original vp3
2901      * but previous versions have the image flipped relative to vp3 */
2902     if (s->theora < 0x030200) {
2903         s->flipped_image = 1;
2904         av_log(avctx, AV_LOG_DEBUG,
2905                "Old (<alpha3) Theora bitstream, flipped image\n");
2906     }
2907 
2908     visible_width  =
2909     s->width       = get_bits(gb, 16) << 4;
2910     visible_height =
2911     s->height      = get_bits(gb, 16) << 4;
2912 
2913     if (s->theora >= 0x030200) {
2914         visible_width  = get_bits(gb, 24);
2915         visible_height = get_bits(gb, 24);
2916 
2917         offset_x = get_bits(gb, 8); /* offset x */
2918         offset_y = get_bits(gb, 8); /* offset y, from bottom */
2919     }
2920 
2921     /* sanity check */
2922     if (av_image_check_size(visible_width, visible_height, 0, avctx) < 0 ||
2923         visible_width  + offset_x > s->width ||
2924         visible_height + offset_y > s->height ||
2925         visible_width < 18
2926     ) {
2927         av_log(avctx, AV_LOG_ERROR,
2928                "Invalid frame dimensions - w:%d h:%d x:%d y:%d (%dx%d).\n",
2929                visible_width, visible_height, offset_x, offset_y,
2930                s->width, s->height);
2931         return AVERROR_INVALIDDATA;
2932     }
2933 
2934     fps.num = get_bits_long(gb, 32);
2935     fps.den = get_bits_long(gb, 32);
2936     if (fps.num && fps.den) {
2937         if (fps.num < 0 || fps.den < 0) {
2938             av_log(avctx, AV_LOG_ERROR, "Invalid framerate\n");
2939             return AVERROR_INVALIDDATA;
2940         }
2941         av_reduce(&avctx->framerate.den, &avctx->framerate.num,
2942                   fps.den, fps.num, 1 << 30);
2943     }
2944 
2945     aspect.num = get_bits(gb, 24);
2946     aspect.den = get_bits(gb, 24);
2947     if (aspect.num && aspect.den) {
2948         av_reduce(&avctx->sample_aspect_ratio.num,
2949                   &avctx->sample_aspect_ratio.den,
2950                   aspect.num, aspect.den, 1 << 30);
2951         ff_set_sar(avctx, avctx->sample_aspect_ratio);
2952     }
2953 
2954     if (s->theora < 0x030200)
2955         skip_bits(gb, 5); /* keyframe frequency force */
2956     colorspace = get_bits(gb, 8);
2957     skip_bits(gb, 24); /* bitrate */
2958 
2959     skip_bits(gb, 6); /* quality hint */
2960 
2961     if (s->theora >= 0x030200) {
2962         skip_bits(gb, 5); /* keyframe frequency force */
2963         avctx->pix_fmt = theora_pix_fmts[get_bits(gb, 2)];
2964         if (avctx->pix_fmt == AV_PIX_FMT_NONE) {
2965             av_log(avctx, AV_LOG_ERROR, "Invalid pixel format\n");
2966             return AVERROR_INVALIDDATA;
2967         }
2968         skip_bits(gb, 3); /* reserved */
2969     } else
2970         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
2971 
2972     if (s->width < 18)
2973         return AVERROR_PATCHWELCOME;
2974     ret = ff_set_dimensions(avctx, s->width, s->height);
2975     if (ret < 0)
2976         return ret;
2977     if (!(avctx->flags2 & AV_CODEC_FLAG2_IGNORE_CROP)) {
2978         avctx->width  = visible_width;
2979         avctx->height = visible_height;
2980         // translate offsets from theora axis ([0,0] lower left)
2981         // to normal axis ([0,0] upper left)
2982         s->offset_x = offset_x;
2983         s->offset_y = s->height - visible_height - offset_y;
2984     }
2985 
2986     if (colorspace == 1)
2987         avctx->color_primaries = AVCOL_PRI_BT470M;
2988     else if (colorspace == 2)
2989         avctx->color_primaries = AVCOL_PRI_BT470BG;
2990 
2991     if (colorspace == 1 || colorspace == 2) {
2992         avctx->colorspace = AVCOL_SPC_BT470BG;
2993         avctx->color_trc  = AVCOL_TRC_BT709;
2994     }
2995 
2996     s->theora_header = 1;
2997     return 0;
2998 }
2999 
theora_decode_tables(AVCodecContext * avctx,GetBitContext * gb)3000 static int theora_decode_tables(AVCodecContext *avctx, GetBitContext *gb)
3001 {
3002     Vp3DecodeContext *s = avctx->priv_data;
3003     int i, n, matrices, inter, plane, ret;
3004 
3005     if (!s->theora_header)
3006         return AVERROR_INVALIDDATA;
3007 
3008     if (s->theora >= 0x030200) {
3009         n = get_bits(gb, 3);
3010         /* loop filter limit values table */
3011         if (n)
3012             for (i = 0; i < 64; i++)
3013                 s->filter_limit_values[i] = get_bits(gb, n);
3014     }
3015 
3016     if (s->theora >= 0x030200)
3017         n = get_bits(gb, 4) + 1;
3018     else
3019         n = 16;
3020     /* quality threshold table */
3021     for (i = 0; i < 64; i++)
3022         s->coded_ac_scale_factor[i] = get_bits(gb, n);
3023 
3024     if (s->theora >= 0x030200)
3025         n = get_bits(gb, 4) + 1;
3026     else
3027         n = 16;
3028     /* dc scale factor table */
3029     for (i = 0; i < 64; i++)
3030         s->coded_dc_scale_factor[0][i] =
3031         s->coded_dc_scale_factor[1][i] = get_bits(gb, n);
3032 
3033     if (s->theora >= 0x030200)
3034         matrices = get_bits(gb, 9) + 1;
3035     else
3036         matrices = 3;
3037 
3038     if (matrices > 384) {
3039         av_log(avctx, AV_LOG_ERROR, "invalid number of base matrixes\n");
3040         return -1;
3041     }
3042 
3043     for (n = 0; n < matrices; n++)
3044         for (i = 0; i < 64; i++)
3045             s->base_matrix[n][i] = get_bits(gb, 8);
3046 
3047     for (inter = 0; inter <= 1; inter++) {
3048         for (plane = 0; plane <= 2; plane++) {
3049             int newqr = 1;
3050             if (inter || plane > 0)
3051                 newqr = get_bits1(gb);
3052             if (!newqr) {
3053                 int qtj, plj;
3054                 if (inter && get_bits1(gb)) {
3055                     qtj = 0;
3056                     plj = plane;
3057                 } else {
3058                     qtj = (3 * inter + plane - 1) / 3;
3059                     plj = (plane + 2) % 3;
3060                 }
3061                 s->qr_count[inter][plane] = s->qr_count[qtj][plj];
3062                 memcpy(s->qr_size[inter][plane], s->qr_size[qtj][plj],
3063                        sizeof(s->qr_size[0][0]));
3064                 memcpy(s->qr_base[inter][plane], s->qr_base[qtj][plj],
3065                        sizeof(s->qr_base[0][0]));
3066             } else {
3067                 int qri = 0;
3068                 int qi  = 0;
3069 
3070                 for (;;) {
3071                     i = get_bits(gb, av_log2(matrices - 1) + 1);
3072                     if (i >= matrices) {
3073                         av_log(avctx, AV_LOG_ERROR,
3074                                "invalid base matrix index\n");
3075                         return -1;
3076                     }
3077                     s->qr_base[inter][plane][qri] = i;
3078                     if (qi >= 63)
3079                         break;
3080                     i = get_bits(gb, av_log2(63 - qi) + 1) + 1;
3081                     s->qr_size[inter][plane][qri++] = i;
3082                     qi += i;
3083                 }
3084 
3085                 if (qi > 63) {
3086                     av_log(avctx, AV_LOG_ERROR, "invalid qi %d > 63\n", qi);
3087                     return -1;
3088                 }
3089                 s->qr_count[inter][plane] = qri;
3090             }
3091         }
3092     }
3093 
3094     /* Huffman tables */
3095     for (int i = 0; i < FF_ARRAY_ELEMS(s->huffman_table); i++) {
3096         s->huffman_table[i].nb_entries = 0;
3097         if ((ret = read_huffman_tree(&s->huffman_table[i], gb, 0, avctx)) < 0)
3098             return ret;
3099     }
3100 
3101     s->theora_tables = 1;
3102 
3103     return 0;
3104 }
3105 
theora_decode_init(AVCodecContext * avctx)3106 static av_cold int theora_decode_init(AVCodecContext *avctx)
3107 {
3108     Vp3DecodeContext *s = avctx->priv_data;
3109     GetBitContext gb;
3110     int ptype;
3111     const uint8_t *header_start[3];
3112     int header_len[3];
3113     int i;
3114     int ret;
3115 
3116     avctx->pix_fmt = AV_PIX_FMT_YUV420P;
3117 
3118     s->theora = 1;
3119 
3120     if (!avctx->extradata_size) {
3121         av_log(avctx, AV_LOG_ERROR, "Missing extradata!\n");
3122         return -1;
3123     }
3124 
3125     if (avpriv_split_xiph_headers(avctx->extradata, avctx->extradata_size,
3126                                   42, header_start, header_len) < 0) {
3127         av_log(avctx, AV_LOG_ERROR, "Corrupt extradata\n");
3128         return -1;
3129     }
3130 
3131     for (i = 0; i < 3; i++) {
3132         if (header_len[i] <= 0)
3133             continue;
3134         ret = init_get_bits8(&gb, header_start[i], header_len[i]);
3135         if (ret < 0)
3136             return ret;
3137 
3138         ptype = get_bits(&gb, 8);
3139 
3140         if (!(ptype & 0x80)) {
3141             av_log(avctx, AV_LOG_ERROR, "Invalid extradata!\n");
3142 //          return -1;
3143         }
3144 
3145         // FIXME: Check for this as well.
3146         skip_bits_long(&gb, 6 * 8); /* "theora" */
3147 
3148         switch (ptype) {
3149         case 0x80:
3150             if (theora_decode_header(avctx, &gb) < 0)
3151                 return -1;
3152             break;
3153         case 0x81:
3154 // FIXME: is this needed? it breaks sometimes
3155 //            theora_decode_comments(avctx, gb);
3156             break;
3157         case 0x82:
3158             if (theora_decode_tables(avctx, &gb))
3159                 return -1;
3160             break;
3161         default:
3162             av_log(avctx, AV_LOG_ERROR,
3163                    "Unknown Theora config packet: %d\n", ptype & ~0x80);
3164             break;
3165         }
3166         if (ptype != 0x81 && get_bits_left(&gb) >= 8U)
3167             av_log(avctx, AV_LOG_WARNING,
3168                    "%d bits left in packet %X\n",
3169                    get_bits_left(&gb), ptype);
3170         if (s->theora < 0x030200)
3171             break;
3172     }
3173 
3174     return vp3_decode_init(avctx);
3175 }
3176 
3177 const FFCodec ff_theora_decoder = {
3178     .p.name                = "theora",
3179     .p.long_name           = NULL_IF_CONFIG_SMALL("Theora"),
3180     .p.type                = AVMEDIA_TYPE_VIDEO,
3181     .p.id                  = AV_CODEC_ID_THEORA,
3182     .priv_data_size        = sizeof(Vp3DecodeContext),
3183     .init                  = theora_decode_init,
3184     .close                 = vp3_decode_end,
3185     FF_CODEC_DECODE_CB(vp3_decode_frame),
3186     .p.capabilities        = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DRAW_HORIZ_BAND |
3187                              AV_CODEC_CAP_FRAME_THREADS,
3188     .flush                 = vp3_decode_flush,
3189     .update_thread_context = ONLY_IF_THREADS_ENABLED(vp3_update_thread_context),
3190     .caps_internal         = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP |
3191                              FF_CODEC_CAP_EXPORTS_CROPPING | FF_CODEC_CAP_ALLOCATE_PROGRESS,
3192 };
3193 #endif
3194 
3195 const FFCodec ff_vp3_decoder = {
3196     .p.name                = "vp3",
3197     .p.long_name           = NULL_IF_CONFIG_SMALL("On2 VP3"),
3198     .p.type                = AVMEDIA_TYPE_VIDEO,
3199     .p.id                  = AV_CODEC_ID_VP3,
3200     .priv_data_size        = sizeof(Vp3DecodeContext),
3201     .init                  = vp3_decode_init,
3202     .close                 = vp3_decode_end,
3203     FF_CODEC_DECODE_CB(vp3_decode_frame),
3204     .p.capabilities        = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DRAW_HORIZ_BAND |
3205                              AV_CODEC_CAP_FRAME_THREADS,
3206     .flush                 = vp3_decode_flush,
3207     .update_thread_context = ONLY_IF_THREADS_ENABLED(vp3_update_thread_context),
3208     .caps_internal         = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP |
3209                              FF_CODEC_CAP_ALLOCATE_PROGRESS,
3210 };
3211 
3212 #if CONFIG_VP4_DECODER
3213 const FFCodec ff_vp4_decoder = {
3214     .p.name                = "vp4",
3215     .p.long_name           = NULL_IF_CONFIG_SMALL("On2 VP4"),
3216     .p.type                = AVMEDIA_TYPE_VIDEO,
3217     .p.id                  = AV_CODEC_ID_VP4,
3218     .priv_data_size        = sizeof(Vp3DecodeContext),
3219     .init                  = vp3_decode_init,
3220     .close                 = vp3_decode_end,
3221     FF_CODEC_DECODE_CB(vp3_decode_frame),
3222     .p.capabilities        = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DRAW_HORIZ_BAND |
3223                              AV_CODEC_CAP_FRAME_THREADS,
3224     .flush                 = vp3_decode_flush,
3225     .update_thread_context = ONLY_IF_THREADS_ENABLED(vp3_update_thread_context),
3226     .caps_internal         = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP |
3227                              FF_CODEC_CAP_ALLOCATE_PROGRESS,
3228 };
3229 #endif
3230