• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * SVQ1 decoder
3  * ported to MPlayer by Arpi <arpi@thot.banki.hu>
4  * ported to libavcodec by Nick Kurshev <nickols_k@mail.ru>
5  *
6  * Copyright (c) 2002 The Xine project
7  * Copyright (c) 2002 The FFmpeg project
8  *
9  * SVQ1 Encoder (c) 2004 Mike Melanson <melanson@pcisys.net>
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * Sorenson Vector Quantizer #1 (SVQ1) video codec.
31  * For more information of the SVQ1 algorithm, visit:
32  *   http://www.pcisys.net/~melanson/codecs/
33  */
34 
35 #include "libavutil/crc.h"
36 #include "libavutil/thread.h"
37 
38 #include "avcodec.h"
39 #include "get_bits.h"
40 #include "h263.h"
41 #include "hpeldsp.h"
42 #include "internal.h"
43 #include "mathops.h"
44 #include "svq1.h"
45 
46 #define SVQ1_BLOCK_TYPE_VLC_BITS 3
47 static VLC svq1_block_type;
48 static VLC svq1_motion_component;
49 static VLC svq1_intra_multistage[6];
50 static VLC svq1_inter_multistage[6];
51 static VLC svq1_intra_mean;
52 static VLC svq1_inter_mean;
53 
54 /* motion vector (prediction) */
55 typedef struct svq1_pmv_s {
56     int x;
57     int y;
58 } svq1_pmv;
59 
60 typedef struct SVQ1Context {
61     HpelDSPContext hdsp;
62     GetBitContext gb;
63     AVFrame *prev;
64 
65     uint8_t *pkt_swapped;
66     int pkt_swapped_allocated;
67 
68     svq1_pmv *pmv;
69     int pmv_allocated;
70 
71     int width;
72     int height;
73     int frame_code;
74     int nonref;         // 1 if the current frame won't be referenced
75 } SVQ1Context;
76 
77 static const uint8_t string_table[256] = {
78     0x00, 0xD5, 0x7F, 0xAA, 0xFE, 0x2B, 0x81, 0x54,
79     0x29, 0xFC, 0x56, 0x83, 0xD7, 0x02, 0xA8, 0x7D,
80     0x52, 0x87, 0x2D, 0xF8, 0xAC, 0x79, 0xD3, 0x06,
81     0x7B, 0xAE, 0x04, 0xD1, 0x85, 0x50, 0xFA, 0x2F,
82     0xA4, 0x71, 0xDB, 0x0E, 0x5A, 0x8F, 0x25, 0xF0,
83     0x8D, 0x58, 0xF2, 0x27, 0x73, 0xA6, 0x0C, 0xD9,
84     0xF6, 0x23, 0x89, 0x5C, 0x08, 0xDD, 0x77, 0xA2,
85     0xDF, 0x0A, 0xA0, 0x75, 0x21, 0xF4, 0x5E, 0x8B,
86     0x9D, 0x48, 0xE2, 0x37, 0x63, 0xB6, 0x1C, 0xC9,
87     0xB4, 0x61, 0xCB, 0x1E, 0x4A, 0x9F, 0x35, 0xE0,
88     0xCF, 0x1A, 0xB0, 0x65, 0x31, 0xE4, 0x4E, 0x9B,
89     0xE6, 0x33, 0x99, 0x4C, 0x18, 0xCD, 0x67, 0xB2,
90     0x39, 0xEC, 0x46, 0x93, 0xC7, 0x12, 0xB8, 0x6D,
91     0x10, 0xC5, 0x6F, 0xBA, 0xEE, 0x3B, 0x91, 0x44,
92     0x6B, 0xBE, 0x14, 0xC1, 0x95, 0x40, 0xEA, 0x3F,
93     0x42, 0x97, 0x3D, 0xE8, 0xBC, 0x69, 0xC3, 0x16,
94     0xEF, 0x3A, 0x90, 0x45, 0x11, 0xC4, 0x6E, 0xBB,
95     0xC6, 0x13, 0xB9, 0x6C, 0x38, 0xED, 0x47, 0x92,
96     0xBD, 0x68, 0xC2, 0x17, 0x43, 0x96, 0x3C, 0xE9,
97     0x94, 0x41, 0xEB, 0x3E, 0x6A, 0xBF, 0x15, 0xC0,
98     0x4B, 0x9E, 0x34, 0xE1, 0xB5, 0x60, 0xCA, 0x1F,
99     0x62, 0xB7, 0x1D, 0xC8, 0x9C, 0x49, 0xE3, 0x36,
100     0x19, 0xCC, 0x66, 0xB3, 0xE7, 0x32, 0x98, 0x4D,
101     0x30, 0xE5, 0x4F, 0x9A, 0xCE, 0x1B, 0xB1, 0x64,
102     0x72, 0xA7, 0x0D, 0xD8, 0x8C, 0x59, 0xF3, 0x26,
103     0x5B, 0x8E, 0x24, 0xF1, 0xA5, 0x70, 0xDA, 0x0F,
104     0x20, 0xF5, 0x5F, 0x8A, 0xDE, 0x0B, 0xA1, 0x74,
105     0x09, 0xDC, 0x76, 0xA3, 0xF7, 0x22, 0x88, 0x5D,
106     0xD6, 0x03, 0xA9, 0x7C, 0x28, 0xFD, 0x57, 0x82,
107     0xFF, 0x2A, 0x80, 0x55, 0x01, 0xD4, 0x7E, 0xAB,
108     0x84, 0x51, 0xFB, 0x2E, 0x7A, 0xAF, 0x05, 0xD0,
109     0xAD, 0x78, 0xD2, 0x07, 0x53, 0x86, 0x2C, 0xF9
110 };
111 
112 #define SVQ1_PROCESS_VECTOR()                                           \
113     for (; level > 0; i++) {                                            \
114         /* process next depth */                                        \
115         if (i == m) {                                                   \
116             m = n;                                                      \
117             if (--level == 0)                                           \
118                 break;                                                  \
119         }                                                               \
120         /* divide block if next bit set */                              \
121         if (!get_bits1(bitbuf))                                         \
122             break;                                                      \
123         /* add child nodes */                                           \
124         list[n++] = list[i];                                            \
125         list[n++] = list[i] + (((level & 1) ? pitch : 1) << ((level >> 1) + 1));\
126     }
127 
128 #define SVQ1_ADD_CODEBOOK()                                             \
129     /* add codebook entries to vector */                                \
130     for (j = 0; j < stages; j++) {                                      \
131         n3  = codebook[entries[j]] ^ 0x80808080;                        \
132         n1 += (n3 & 0xFF00FF00) >> 8;                                   \
133         n2 +=  n3 & 0x00FF00FF;                                         \
134     }                                                                   \
135                                                                         \
136     /* clip to [0..255] */                                              \
137     if (n1 & 0xFF00FF00) {                                              \
138         n3  = (n1 >> 15  & 0x00010001 | 0x01000100) - 0x00010001;       \
139         n1 += 0x7F007F00;                                               \
140         n1 |= (~n1 >> 15 & 0x00010001 | 0x01000100) - 0x00010001;       \
141         n1 &= n3 & 0x00FF00FF;                                          \
142     }                                                                   \
143                                                                         \
144     if (n2 & 0xFF00FF00) {                                              \
145         n3  = (n2 >> 15  & 0x00010001 | 0x01000100) - 0x00010001;       \
146         n2 += 0x7F007F00;                                               \
147         n2 |= (~n2 >> 15 & 0x00010001 | 0x01000100) - 0x00010001;       \
148         n2 &= n3 & 0x00FF00FF;                                          \
149     }
150 
151 #define SVQ1_CALC_CODEBOOK_ENTRIES(cbook)                               \
152     codebook = (const uint32_t *)cbook[level];                          \
153     if (stages > 0)                                                     \
154         bit_cache = get_bits(bitbuf, 4 * stages);                       \
155     /* calculate codebook entries for this vector */                    \
156     for (j = 0; j < stages; j++) {                                      \
157         entries[j] = (((bit_cache >> (4 * (stages - j - 1))) & 0xF) +   \
158                       16 * j) << (level + 1);                           \
159     }                                                                   \
160     mean -= stages * 128;                                               \
161     n4    = (mean << 16) + mean;
162 
svq1_decode_block_intra(GetBitContext * bitbuf,uint8_t * pixels,ptrdiff_t pitch)163 static int svq1_decode_block_intra(GetBitContext *bitbuf, uint8_t *pixels,
164                                    ptrdiff_t pitch)
165 {
166     uint32_t bit_cache;
167     uint8_t *list[63];
168     uint32_t *dst;
169     const uint32_t *codebook;
170     int entries[6];
171     int i, j, m, n;
172     int stages;
173     unsigned mean;
174     unsigned x, y, width, height, level;
175     uint32_t n1, n2, n3, n4;
176 
177     /* initialize list for breadth first processing of vectors */
178     list[0] = pixels;
179 
180     /* recursively process vector */
181     for (i = 0, m = 1, n = 1, level = 5; i < n; i++) {
182         SVQ1_PROCESS_VECTOR();
183 
184         /* destination address and vector size */
185         dst    = (uint32_t *)list[i];
186         width  = 1 << ((4 + level) / 2);
187         height = 1 << ((3 + level) / 2);
188 
189         /* get number of stages (-1 skips vector, 0 for mean only) */
190         stages = get_vlc2(bitbuf, svq1_intra_multistage[level].table, 3, 3) - 1;
191 
192         if (stages == -1) {
193             for (y = 0; y < height; y++)
194                 memset(&dst[y * (pitch / 4)], 0, width);
195             continue;   /* skip vector */
196         }
197 
198         if ((stages > 0 && level >= 4)) {
199             ff_dlog(NULL,
200                     "Error (svq1_decode_block_intra): invalid vector: stages=%i level=%i\n",
201                     stages, level);
202             return AVERROR_INVALIDDATA;  /* invalid vector */
203         }
204         av_assert0(stages >= 0);
205 
206         mean = get_vlc2(bitbuf, svq1_intra_mean.table, 8, 3);
207 
208         if (stages == 0) {
209             for (y = 0; y < height; y++)
210                 memset(&dst[y * (pitch / 4)], mean, width);
211         } else {
212             SVQ1_CALC_CODEBOOK_ENTRIES(ff_svq1_intra_codebooks);
213 
214             for (y = 0; y < height; y++) {
215                 for (x = 0; x < width / 4; x++, codebook++) {
216                     n1 = n4;
217                     n2 = n4;
218                     SVQ1_ADD_CODEBOOK()
219                     /* store result */
220                     dst[x] = n1 << 8 | n2;
221                 }
222                 dst += pitch / 4;
223             }
224         }
225     }
226 
227     return 0;
228 }
229 
svq1_decode_block_non_intra(GetBitContext * bitbuf,uint8_t * pixels,ptrdiff_t pitch)230 static int svq1_decode_block_non_intra(GetBitContext *bitbuf, uint8_t *pixels,
231                                        ptrdiff_t pitch)
232 {
233     uint32_t bit_cache;
234     uint8_t *list[63];
235     uint32_t *dst;
236     const uint32_t *codebook;
237     int entries[6];
238     int i, j, m, n;
239     int stages;
240     unsigned mean;
241     int x, y, width, height, level;
242     uint32_t n1, n2, n3, n4;
243 
244     /* initialize list for breadth first processing of vectors */
245     list[0] = pixels;
246 
247     /* recursively process vector */
248     for (i = 0, m = 1, n = 1, level = 5; i < n; i++) {
249         SVQ1_PROCESS_VECTOR();
250 
251         /* destination address and vector size */
252         dst    = (uint32_t *)list[i];
253         width  = 1 << ((4 + level) / 2);
254         height = 1 << ((3 + level) / 2);
255 
256         /* get number of stages (-1 skips vector, 0 for mean only) */
257         stages = get_vlc2(bitbuf, svq1_inter_multistage[level].table, 3, 2) - 1;
258 
259         if (stages == -1)
260             continue;           /* skip vector */
261 
262         if ((stages > 0 && level >= 4)) {
263             ff_dlog(NULL,
264                     "Error (svq1_decode_block_non_intra): invalid vector: stages=%i level=%i\n",
265                     stages, level);
266             return AVERROR_INVALIDDATA;  /* invalid vector */
267         }
268         av_assert0(stages >= 0);
269 
270         mean = get_vlc2(bitbuf, svq1_inter_mean.table, 9, 3) - 256;
271 
272         SVQ1_CALC_CODEBOOK_ENTRIES(ff_svq1_inter_codebooks);
273 
274         for (y = 0; y < height; y++) {
275             for (x = 0; x < width / 4; x++, codebook++) {
276                 n3 = dst[x];
277                 /* add mean value to vector */
278                 n1 = n4 + ((n3 & 0xFF00FF00) >> 8);
279                 n2 = n4 +  (n3 & 0x00FF00FF);
280                 SVQ1_ADD_CODEBOOK()
281                 /* store result */
282                 dst[x] = n1 << 8 | n2;
283             }
284             dst += pitch / 4;
285         }
286     }
287     return 0;
288 }
289 
svq1_decode_motion_vector(GetBitContext * bitbuf,svq1_pmv * mv,svq1_pmv ** pmv)290 static int svq1_decode_motion_vector(GetBitContext *bitbuf, svq1_pmv *mv,
291                                      svq1_pmv **pmv)
292 {
293     int diff;
294     int i;
295 
296     for (i = 0; i < 2; i++) {
297         /* get motion code */
298         diff = get_vlc2(bitbuf, svq1_motion_component.table, 7, 2);
299         if (diff < 0)
300             return AVERROR_INVALIDDATA;
301         else if (diff) {
302             if (get_bits1(bitbuf))
303                 diff = -diff;
304         }
305 
306         /* add median of motion vector predictors and clip result */
307         if (i == 1)
308             mv->y = sign_extend(diff + mid_pred(pmv[0]->y, pmv[1]->y, pmv[2]->y), 6);
309         else
310             mv->x = sign_extend(diff + mid_pred(pmv[0]->x, pmv[1]->x, pmv[2]->x), 6);
311     }
312 
313     return 0;
314 }
315 
svq1_skip_block(uint8_t * current,uint8_t * previous,ptrdiff_t pitch,int x,int y)316 static void svq1_skip_block(uint8_t *current, uint8_t *previous,
317                             ptrdiff_t pitch, int x, int y)
318 {
319     uint8_t *src;
320     uint8_t *dst;
321     int i;
322 
323     src = &previous[x + y * pitch];
324     dst = current;
325 
326     for (i = 0; i < 16; i++) {
327         memcpy(dst, src, 16);
328         src += pitch;
329         dst += pitch;
330     }
331 }
332 
svq1_motion_inter_block(HpelDSPContext * hdsp,GetBitContext * bitbuf,uint8_t * current,uint8_t * previous,ptrdiff_t pitch,svq1_pmv * motion,int x,int y,int width,int height)333 static int svq1_motion_inter_block(HpelDSPContext *hdsp, GetBitContext *bitbuf,
334                                    uint8_t *current, uint8_t *previous,
335                                    ptrdiff_t pitch, svq1_pmv *motion, int x, int y,
336                                    int width, int height)
337 {
338     uint8_t *src;
339     uint8_t *dst;
340     svq1_pmv mv;
341     svq1_pmv *pmv[3];
342     int result;
343 
344     /* predict and decode motion vector */
345     pmv[0] = &motion[0];
346     if (y == 0) {
347         pmv[1] =
348         pmv[2] = pmv[0];
349     } else {
350         pmv[1] = &motion[x / 8 + 2];
351         pmv[2] = &motion[x / 8 + 4];
352     }
353 
354     result = svq1_decode_motion_vector(bitbuf, &mv, pmv);
355     if (result)
356         return result;
357 
358     motion[0].x         =
359     motion[x / 8 + 2].x =
360     motion[x / 8 + 3].x = mv.x;
361     motion[0].y         =
362     motion[x / 8 + 2].y =
363     motion[x / 8 + 3].y = mv.y;
364 
365     mv.x = av_clip(mv.x, -2 * x, 2 * (width  - x - 16));
366     mv.y = av_clip(mv.y, -2 * y, 2 * (height - y - 16));
367 
368     src = &previous[(x + (mv.x >> 1)) + (y + (mv.y >> 1)) * pitch];
369     dst = current;
370 
371     hdsp->put_pixels_tab[0][(mv.y & 1) << 1 | (mv.x & 1)](dst, src, pitch, 16);
372 
373     return 0;
374 }
375 
svq1_motion_inter_4v_block(HpelDSPContext * hdsp,GetBitContext * bitbuf,uint8_t * current,uint8_t * previous,ptrdiff_t pitch,svq1_pmv * motion,int x,int y,int width,int height)376 static int svq1_motion_inter_4v_block(HpelDSPContext *hdsp, GetBitContext *bitbuf,
377                                       uint8_t *current, uint8_t *previous,
378                                       ptrdiff_t pitch, svq1_pmv *motion, int x, int y,
379                                       int width, int height)
380 {
381     uint8_t *src;
382     uint8_t *dst;
383     svq1_pmv mv;
384     svq1_pmv *pmv[4];
385     int i, result;
386 
387     /* predict and decode motion vector (0) */
388     pmv[0] = &motion[0];
389     if (y == 0) {
390         pmv[1] =
391         pmv[2] = pmv[0];
392     } else {
393         pmv[1] = &motion[(x / 8) + 2];
394         pmv[2] = &motion[(x / 8) + 4];
395     }
396 
397     result = svq1_decode_motion_vector(bitbuf, &mv, pmv);
398     if (result)
399         return result;
400 
401     /* predict and decode motion vector (1) */
402     pmv[0] = &mv;
403     if (y == 0) {
404         pmv[1] =
405         pmv[2] = pmv[0];
406     } else {
407         pmv[1] = &motion[(x / 8) + 3];
408     }
409     result = svq1_decode_motion_vector(bitbuf, &motion[0], pmv);
410     if (result)
411         return result;
412 
413     /* predict and decode motion vector (2) */
414     pmv[1] = &motion[0];
415     pmv[2] = &motion[(x / 8) + 1];
416 
417     result = svq1_decode_motion_vector(bitbuf, &motion[(x / 8) + 2], pmv);
418     if (result)
419         return result;
420 
421     /* predict and decode motion vector (3) */
422     pmv[2] = &motion[(x / 8) + 2];
423     pmv[3] = &motion[(x / 8) + 3];
424 
425     result = svq1_decode_motion_vector(bitbuf, pmv[3], pmv);
426     if (result)
427         return result;
428 
429     /* form predictions */
430     for (i = 0; i < 4; i++) {
431         int mvx = pmv[i]->x + (i  & 1) * 16;
432         int mvy = pmv[i]->y + (i >> 1) * 16;
433 
434         // FIXME: clipping or padding?
435         mvx = av_clip(mvx, -2 * x, 2 * (width  - x - 8));
436         mvy = av_clip(mvy, -2 * y, 2 * (height - y - 8));
437 
438         src = &previous[(x + (mvx >> 1)) + (y + (mvy >> 1)) * pitch];
439         dst = current;
440 
441         hdsp->put_pixels_tab[1][((mvy & 1) << 1) | (mvx & 1)](dst, src, pitch, 8);
442 
443         /* select next block */
444         if (i & 1)
445             current += 8 * (pitch - 1);
446         else
447             current += 8;
448     }
449 
450     return 0;
451 }
452 
svq1_decode_delta_block(AVCodecContext * avctx,HpelDSPContext * hdsp,GetBitContext * bitbuf,uint8_t * current,uint8_t * previous,ptrdiff_t pitch,svq1_pmv * motion,int x,int y,int width,int height)453 static int svq1_decode_delta_block(AVCodecContext *avctx, HpelDSPContext *hdsp,
454                                    GetBitContext *bitbuf,
455                                    uint8_t *current, uint8_t *previous,
456                                    ptrdiff_t pitch, svq1_pmv *motion, int x, int y,
457                                    int width, int height)
458 {
459     uint32_t block_type;
460     int result = 0;
461 
462     /* get block type */
463     block_type = get_vlc2(bitbuf, svq1_block_type.table,
464                           SVQ1_BLOCK_TYPE_VLC_BITS, 1);
465 
466     /* reset motion vectors */
467     if (block_type == SVQ1_BLOCK_SKIP || block_type == SVQ1_BLOCK_INTRA) {
468         motion[0].x         =
469         motion[0].y         =
470         motion[x / 8 + 2].x =
471         motion[x / 8 + 2].y =
472         motion[x / 8 + 3].x =
473         motion[x / 8 + 3].y = 0;
474     }
475 
476     switch (block_type) {
477     case SVQ1_BLOCK_SKIP:
478         svq1_skip_block(current, previous, pitch, x, y);
479         break;
480 
481     case SVQ1_BLOCK_INTER:
482         result = svq1_motion_inter_block(hdsp, bitbuf, current, previous,
483                                          pitch, motion, x, y, width, height);
484 
485         if (result != 0) {
486             ff_dlog(avctx, "Error in svq1_motion_inter_block %i\n", result);
487             break;
488         }
489         result = svq1_decode_block_non_intra(bitbuf, current, pitch);
490         break;
491 
492     case SVQ1_BLOCK_INTER_4V:
493         result = svq1_motion_inter_4v_block(hdsp, bitbuf, current, previous,
494                                             pitch, motion, x, y, width, height);
495 
496         if (result != 0) {
497             ff_dlog(avctx, "Error in svq1_motion_inter_4v_block %i\n", result);
498             break;
499         }
500         result = svq1_decode_block_non_intra(bitbuf, current, pitch);
501         break;
502 
503     case SVQ1_BLOCK_INTRA:
504         result = svq1_decode_block_intra(bitbuf, current, pitch);
505         break;
506     }
507 
508     return result;
509 }
510 
svq1_parse_string(GetBitContext * bitbuf,uint8_t out[257])511 static void svq1_parse_string(GetBitContext *bitbuf, uint8_t out[257])
512 {
513     uint8_t seed;
514     int i;
515 
516     out[0] = get_bits(bitbuf, 8);
517     seed   = string_table[out[0]];
518 
519     for (i = 1; i <= out[0]; i++) {
520         out[i] = get_bits(bitbuf, 8) ^ seed;
521         seed   = string_table[out[i] ^ seed];
522     }
523     out[i] = 0;
524 }
525 
svq1_decode_frame_header(AVCodecContext * avctx,AVFrame * frame)526 static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)
527 {
528     SVQ1Context *s = avctx->priv_data;
529     GetBitContext *bitbuf = &s->gb;
530     int frame_size_code;
531     int width  = s->width;
532     int height = s->height;
533 
534     skip_bits(bitbuf, 8); /* temporal_reference */
535 
536     /* frame type */
537     s->nonref = 0;
538     switch (get_bits(bitbuf, 2)) {
539     case 0:
540         frame->pict_type = AV_PICTURE_TYPE_I;
541         break;
542     case 2:
543         s->nonref = 1;
544     case 1:
545         frame->pict_type = AV_PICTURE_TYPE_P;
546         break;
547     default:
548         av_log(avctx, AV_LOG_ERROR, "Invalid frame type.\n");
549         return AVERROR_INVALIDDATA;
550     }
551 
552     if (frame->pict_type == AV_PICTURE_TYPE_I) {
553         /* unknown fields */
554         if (s->frame_code == 0x50 || s->frame_code == 0x60) {
555             int csum = get_bits(bitbuf, 16);
556 
557             csum = av_bswap16(av_crc(av_crc_get_table(AV_CRC_16_CCITT), av_bswap16(csum), bitbuf->buffer, bitbuf->size_in_bits >> 3));
558 
559             ff_dlog(avctx, "%s checksum (%02x) for packet data\n",
560                     (csum == 0) ? "correct" : "incorrect", csum);
561         }
562 
563         if ((s->frame_code ^ 0x10) >= 0x50) {
564             uint8_t msg[257];
565 
566             svq1_parse_string(bitbuf, msg);
567 
568             av_log(avctx, AV_LOG_INFO,
569                    "embedded message:\n%s\n", ((char *)msg) + 1);
570         }
571 
572         skip_bits(bitbuf, 2);
573         skip_bits(bitbuf, 2);
574         skip_bits1(bitbuf);
575 
576         /* load frame size */
577         frame_size_code = get_bits(bitbuf, 3);
578 
579         if (frame_size_code == 7) {
580             /* load width, height (12 bits each) */
581             width  = get_bits(bitbuf, 12);
582             height = get_bits(bitbuf, 12);
583 
584             if (!width || !height)
585                 return AVERROR_INVALIDDATA;
586         } else {
587             /* get width, height from table */
588             width  = ff_svq1_frame_size_table[frame_size_code][0];
589             height = ff_svq1_frame_size_table[frame_size_code][1];
590         }
591     }
592 
593     /* unknown fields */
594     if (get_bits1(bitbuf)) {
595         skip_bits1(bitbuf);    /* use packet checksum if (1) */
596         skip_bits1(bitbuf);    /* component checksums after image data if (1) */
597 
598         if (get_bits(bitbuf, 2) != 0)
599             return AVERROR_INVALIDDATA;
600     }
601 
602     if (get_bits1(bitbuf)) {
603         skip_bits1(bitbuf);
604         skip_bits(bitbuf, 4);
605         skip_bits1(bitbuf);
606         skip_bits(bitbuf, 2);
607 
608         if (skip_1stop_8data_bits(bitbuf) < 0)
609             return AVERROR_INVALIDDATA;
610     }
611     if (get_bits_left(bitbuf) <= 0)
612         return AVERROR_INVALIDDATA;
613 
614     s->width  = width;
615     s->height = height;
616     return 0;
617 }
618 
svq1_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)619 static int svq1_decode_frame(AVCodecContext *avctx, void *data,
620                              int *got_frame, AVPacket *avpkt)
621 {
622     const uint8_t *buf = avpkt->data;
623     int buf_size       = avpkt->size;
624     SVQ1Context     *s = avctx->priv_data;
625     AVFrame       *cur = data;
626     uint8_t *current;
627     int result, i, x, y, width, height;
628     int ret;
629 
630     /* initialize bit buffer */
631     ret = init_get_bits8(&s->gb, buf, buf_size);
632     if (ret < 0)
633         return ret;
634 
635     /* decode frame header */
636     s->frame_code = get_bits(&s->gb, 22);
637 
638     if ((s->frame_code & ~0x70) || !(s->frame_code & 0x60))
639         return AVERROR_INVALIDDATA;
640 
641     /* swap some header bytes (why?) */
642     if (s->frame_code != 0x20) {
643         uint32_t *src;
644 
645         if (buf_size < 9 * 4) {
646             av_log(avctx, AV_LOG_ERROR, "Input packet too small\n");
647             return AVERROR_INVALIDDATA;
648         }
649 
650         av_fast_padded_malloc(&s->pkt_swapped,
651                               &s->pkt_swapped_allocated,
652                               buf_size);
653         if (!s->pkt_swapped)
654             return AVERROR(ENOMEM);
655 
656         memcpy(s->pkt_swapped, buf, buf_size);
657         buf = s->pkt_swapped;
658         init_get_bits(&s->gb, buf, buf_size * 8);
659         skip_bits(&s->gb, 22);
660 
661         src = (uint32_t *)(s->pkt_swapped + 4);
662 
663         for (i = 0; i < 4; i++)
664             src[i] = ((src[i] << 16) | (src[i] >> 16)) ^ src[7 - i];
665     }
666 
667     result = svq1_decode_frame_header(avctx, cur);
668     if (result != 0) {
669         ff_dlog(avctx, "Error in svq1_decode_frame_header %i\n", result);
670         return result;
671     }
672 
673     result = ff_set_dimensions(avctx, s->width, s->height);
674     if (result < 0)
675         return result;
676 
677     if ((avctx->skip_frame >= AVDISCARD_NONREF && s->nonref) ||
678         (avctx->skip_frame >= AVDISCARD_NONKEY &&
679          cur->pict_type != AV_PICTURE_TYPE_I) ||
680         avctx->skip_frame >= AVDISCARD_ALL)
681         return buf_size;
682 
683     result = ff_get_buffer(avctx, cur, s->nonref ? 0 : AV_GET_BUFFER_FLAG_REF);
684     if (result < 0)
685         return result;
686 
687     av_fast_padded_malloc(&s->pmv, &s->pmv_allocated, (FFALIGN(s->width, 16) / 8 + 3) * sizeof(*s->pmv));
688     if (!s->pmv)
689         return AVERROR(ENOMEM);
690 
691     /* decode y, u and v components */
692     for (i = 0; i < 3; i++) {
693         int linesize = cur->linesize[i];
694         if (i == 0) {
695             width    = FFALIGN(s->width,  16);
696             height   = FFALIGN(s->height, 16);
697         } else {
698             if (avctx->flags & AV_CODEC_FLAG_GRAY)
699                 break;
700             width    = FFALIGN(s->width  / 4, 16);
701             height   = FFALIGN(s->height / 4, 16);
702         }
703 
704         current = cur->data[i];
705 
706         if (cur->pict_type == AV_PICTURE_TYPE_I) {
707             /* keyframe */
708             for (y = 0; y < height; y += 16) {
709                 for (x = 0; x < width; x += 16) {
710                     result = svq1_decode_block_intra(&s->gb, &current[x],
711                                                      linesize);
712                     if (result) {
713                         av_log(avctx, AV_LOG_ERROR,
714                                "Error in svq1_decode_block %i (keyframe)\n",
715                                result);
716                         return result;
717                     }
718                 }
719                 current += 16 * linesize;
720             }
721         } else {
722             /* delta frame */
723             uint8_t *previous = s->prev->data[i];
724             if (!previous ||
725                 s->prev->width != s->width || s->prev->height != s->height) {
726                 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
727                 return AVERROR_INVALIDDATA;
728             }
729 
730             memset(s->pmv, 0, ((width / 8) + 3) * sizeof(svq1_pmv));
731 
732             for (y = 0; y < height; y += 16) {
733                 for (x = 0; x < width; x += 16) {
734                     result = svq1_decode_delta_block(avctx, &s->hdsp,
735                                                      &s->gb, &current[x],
736                                                      previous, linesize,
737                                                      s->pmv, x, y, width, height);
738                     if (result != 0) {
739                         ff_dlog(avctx,
740                                 "Error in svq1_decode_delta_block %i\n",
741                                 result);
742                         return result;
743                     }
744                 }
745 
746                 s->pmv[0].x =
747                 s->pmv[0].y = 0;
748 
749                 current += 16 * linesize;
750             }
751         }
752     }
753 
754     if (!s->nonref) {
755         av_frame_unref(s->prev);
756         result = av_frame_ref(s->prev, cur);
757         if (result < 0)
758             return result;
759     }
760 
761     *got_frame = 1;
762     result     = buf_size;
763 
764     return result;
765 }
766 
svq1_static_init(void)767 static av_cold void svq1_static_init(void)
768 {
769     INIT_VLC_STATIC(&svq1_block_type, SVQ1_BLOCK_TYPE_VLC_BITS, 4,
770                     &ff_svq1_block_type_vlc[0][1], 2, 1,
771                     &ff_svq1_block_type_vlc[0][0], 2, 1, 8);
772 
773     INIT_VLC_STATIC(&svq1_motion_component, 7, 33,
774                     &ff_mvtab[0][1], 2, 1,
775                     &ff_mvtab[0][0], 2, 1, 176);
776 
777     for (int i = 0, offset = 0; i < 6; i++) {
778         static const uint8_t sizes[2][6] = { { 14, 10, 14, 18, 16, 18 },
779                                              { 10, 10, 14, 14, 14, 16 } };
780         static VLC_TYPE table[168][2];
781         svq1_intra_multistage[i].table           = &table[offset];
782         svq1_intra_multistage[i].table_allocated = sizes[0][i];
783         offset                                  += sizes[0][i];
784         init_vlc(&svq1_intra_multistage[i], 3, 8,
785                  &ff_svq1_intra_multistage_vlc[i][0][1], 2, 1,
786                  &ff_svq1_intra_multistage_vlc[i][0][0], 2, 1,
787                  INIT_VLC_USE_NEW_STATIC);
788         svq1_inter_multistage[i].table           = &table[offset];
789         svq1_inter_multistage[i].table_allocated = sizes[1][i];
790         offset                                  += sizes[1][i];
791         init_vlc(&svq1_inter_multistage[i], 3, 8,
792                  &ff_svq1_inter_multistage_vlc[i][0][1], 2, 1,
793                  &ff_svq1_inter_multistage_vlc[i][0][0], 2, 1,
794                  INIT_VLC_USE_NEW_STATIC);
795     }
796 
797     INIT_VLC_STATIC(&svq1_intra_mean, 8, 256,
798                     &ff_svq1_intra_mean_vlc[0][1], 4, 2,
799                     &ff_svq1_intra_mean_vlc[0][0], 4, 2, 632);
800 
801     INIT_VLC_STATIC(&svq1_inter_mean, 9, 512,
802                     &ff_svq1_inter_mean_vlc[0][1], 4, 2,
803                     &ff_svq1_inter_mean_vlc[0][0], 4, 2, 1434);
804 }
805 
svq1_decode_init(AVCodecContext * avctx)806 static av_cold int svq1_decode_init(AVCodecContext *avctx)
807 {
808     static AVOnce init_static_once = AV_ONCE_INIT;
809     SVQ1Context *s = avctx->priv_data;
810 
811     s->prev = av_frame_alloc();
812     if (!s->prev)
813         return AVERROR(ENOMEM);
814 
815     s->width            = avctx->width  + 3 & ~3;
816     s->height           = avctx->height + 3 & ~3;
817     avctx->pix_fmt      = AV_PIX_FMT_YUV410P;
818 
819     ff_hpeldsp_init(&s->hdsp, avctx->flags);
820 
821     ff_thread_once(&init_static_once, svq1_static_init);
822 
823     return 0;
824 }
825 
svq1_decode_end(AVCodecContext * avctx)826 static av_cold int svq1_decode_end(AVCodecContext *avctx)
827 {
828     SVQ1Context *s = avctx->priv_data;
829 
830     av_frame_free(&s->prev);
831     av_freep(&s->pkt_swapped);
832     s->pkt_swapped_allocated = 0;
833     av_freep(&s->pmv);
834     s->pmv_allocated = 0;
835 
836     return 0;
837 }
838 
svq1_flush(AVCodecContext * avctx)839 static void svq1_flush(AVCodecContext *avctx)
840 {
841     SVQ1Context *s = avctx->priv_data;
842 
843     av_frame_unref(s->prev);
844 }
845 
846 AVCodec ff_svq1_decoder = {
847     .name           = "svq1",
848     .long_name      = NULL_IF_CONFIG_SMALL("Sorenson Vector Quantizer 1 / Sorenson Video 1 / SVQ1"),
849     .type           = AVMEDIA_TYPE_VIDEO,
850     .id             = AV_CODEC_ID_SVQ1,
851     .priv_data_size = sizeof(SVQ1Context),
852     .init           = svq1_decode_init,
853     .close          = svq1_decode_end,
854     .decode         = svq1_decode_frame,
855     .capabilities   = AV_CODEC_CAP_DR1,
856     .flush          = svq1_flush,
857     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV410P,
858                                                      AV_PIX_FMT_NONE },
859     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
860 };
861