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1 /*
2  * ATRAC3+ compatible decoder
3  *
4  * Copyright (c) 2010-2013 Maxim Poliakovski
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Bitstream parser for ATRAC3+ decoder.
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "avcodec.h"
30 #include "get_bits.h"
31 #include "atrac3plus.h"
32 #include "atrac3plus_data.h"
33 
34 static VLC_TYPE tables_data[154276][2];
35 static VLC wl_vlc_tabs[4];
36 static VLC sf_vlc_tabs[8];
37 static VLC ct_vlc_tabs[4];
38 static VLC spec_vlc_tabs[112];
39 static VLC gain_vlc_tabs[11];
40 static VLC tone_vlc_tabs[7];
41 
42 /**
43  * Generate canonical VLC table from given descriptor.
44  *
45  * @param[in]     cb          ptr to codebook descriptor
46  * @param[in,out] xlat        ptr to ptr to translation table
47  * @param[in,out] tab_offset  starting offset to the generated vlc table
48  * @param[out]    out_vlc     ptr to vlc table to be generated
49  */
build_canonical_huff(const uint8_t * cb,const uint8_t ** xlat,int * tab_offset,VLC * out_vlc)50 static av_cold void build_canonical_huff(const uint8_t *cb, const uint8_t **xlat,
51                                          int *tab_offset, VLC *out_vlc)
52 {
53     int i, max_len;
54     uint8_t bits[256];
55     int index = 0;
56 
57     for (int b = 1; b <= 12; b++) {
58         for (i = *cb++; i > 0; i--) {
59             av_assert0(index < 256);
60             bits[index]  = b;
61             index++;
62         }
63     }
64     max_len = bits[index - 1];
65 
66     out_vlc->table = &tables_data[*tab_offset];
67     out_vlc->table_allocated = 1 << max_len;
68 
69     ff_init_vlc_from_lengths(out_vlc, max_len, index, bits, 1,
70                              *xlat, 1, 1, 0, INIT_VLC_USE_NEW_STATIC, NULL);
71 
72     *tab_offset += 1 << max_len;
73     *xlat       += index;
74 }
75 
ff_atrac3p_init_vlcs(void)76 av_cold void ff_atrac3p_init_vlcs(void)
77 {
78     int i, tab_offset = 0;
79     const uint8_t *xlats;
80 
81     xlats = atrac3p_wl_ct_xlats;
82     for (int i = 0; i < 4; i++) {
83         build_canonical_huff(atrac3p_wl_cbs[i], &xlats,
84                              &tab_offset, &wl_vlc_tabs[i]);
85         build_canonical_huff(atrac3p_ct_cbs[i], &xlats,
86                              &tab_offset, &ct_vlc_tabs[i]);
87     }
88 
89     xlats = atrac3p_sf_xlats;
90     for (int i = 0; i < 8; i++)
91         build_canonical_huff(atrac3p_sf_cbs[i], &xlats,
92                              &tab_offset, &sf_vlc_tabs[i]);
93 
94     /* build huffman tables for spectrum decoding */
95     xlats = atrac3p_spectra_xlats;
96     for (i = 0; i < 112; i++) {
97         if (atrac3p_spectra_cbs[i][0] >= 0)
98             build_canonical_huff(atrac3p_spectra_cbs[i],
99                                  &xlats, &tab_offset, &spec_vlc_tabs[i]);
100         else /* Reuse already initialized VLC table */
101             spec_vlc_tabs[i] = spec_vlc_tabs[-atrac3p_spectra_cbs[i][0]];
102     }
103 
104     /* build huffman tables for gain data decoding */
105     xlats = atrac3p_gain_xlats;
106     for (i = 0; i < 11; i++)
107         build_canonical_huff(atrac3p_gain_cbs[i], &xlats,
108                              &tab_offset, &gain_vlc_tabs[i]);
109 
110     /* build huffman tables for tone decoding */
111     xlats = atrac3p_tone_xlats;
112     for (i = 0; i < 7; i++)
113         build_canonical_huff(atrac3p_tone_cbs[i], &xlats,
114                              &tab_offset, &tone_vlc_tabs[i]);
115 }
116 
117 /**
118  * Decode number of coded quantization units.
119  *
120  * @param[in]     gb            the GetBit context
121  * @param[in,out] chan          ptr to the channel parameters
122  * @param[in,out] ctx           ptr to the channel unit context
123  * @param[in]     avctx         ptr to the AVCodecContext
124  * @return result code: 0 = OK, otherwise - error code
125  */
num_coded_units(GetBitContext * gb,Atrac3pChanParams * chan,Atrac3pChanUnitCtx * ctx,AVCodecContext * avctx)126 static int num_coded_units(GetBitContext *gb, Atrac3pChanParams *chan,
127                            Atrac3pChanUnitCtx *ctx, AVCodecContext *avctx)
128 {
129     chan->fill_mode = get_bits(gb, 2);
130     if (!chan->fill_mode) {
131         chan->num_coded_vals = ctx->num_quant_units;
132     } else {
133         chan->num_coded_vals = get_bits(gb, 5);
134         if (chan->num_coded_vals > ctx->num_quant_units) {
135             av_log(avctx, AV_LOG_ERROR,
136                    "Invalid number of transmitted units!\n");
137             return AVERROR_INVALIDDATA;
138         }
139 
140         if (chan->fill_mode == 3)
141             chan->split_point = get_bits(gb, 2) + (chan->ch_num << 1) + 1;
142     }
143 
144     return 0;
145 }
146 
147 /**
148  * Add weighting coefficients to the decoded word-length information.
149  *
150  * @param[in,out] ctx           ptr to the channel unit context
151  * @param[in,out] chan          ptr to the channel parameters
152  * @param[in]     wtab_idx      index of the table of weights
153  * @param[in]     avctx         ptr to the AVCodecContext
154  * @return result code: 0 = OK, otherwise - error code
155  */
add_wordlen_weights(Atrac3pChanUnitCtx * ctx,Atrac3pChanParams * chan,int wtab_idx,AVCodecContext * avctx)156 static int add_wordlen_weights(Atrac3pChanUnitCtx *ctx,
157                                Atrac3pChanParams *chan, int wtab_idx,
158                                AVCodecContext *avctx)
159 {
160     int i;
161     const int8_t *weights_tab =
162         &atrac3p_wl_weights[chan->ch_num * 3 + wtab_idx - 1][0];
163 
164     for (i = 0; i < ctx->num_quant_units; i++) {
165         chan->qu_wordlen[i] += weights_tab[i];
166         if (chan->qu_wordlen[i] < 0 || chan->qu_wordlen[i] > 7) {
167             av_log(avctx, AV_LOG_ERROR,
168                    "WL index out of range: pos=%d, val=%d!\n",
169                    i, chan->qu_wordlen[i]);
170             return AVERROR_INVALIDDATA;
171         }
172     }
173 
174     return 0;
175 }
176 
177 /**
178  * Subtract weighting coefficients from decoded scalefactors.
179  *
180  * @param[in,out] ctx           ptr to the channel unit context
181  * @param[in,out] chan          ptr to the channel parameters
182  * @param[in]     wtab_idx      index of table of weights
183  * @param[in]     avctx         ptr to the AVCodecContext
184  * @return result code: 0 = OK, otherwise - error code
185  */
subtract_sf_weights(Atrac3pChanUnitCtx * ctx,Atrac3pChanParams * chan,int wtab_idx,AVCodecContext * avctx)186 static int subtract_sf_weights(Atrac3pChanUnitCtx *ctx,
187                                Atrac3pChanParams *chan, int wtab_idx,
188                                AVCodecContext *avctx)
189 {
190     int i;
191     const int8_t *weights_tab = &atrac3p_sf_weights[wtab_idx - 1][0];
192 
193     for (i = 0; i < ctx->used_quant_units; i++) {
194         chan->qu_sf_idx[i] -= weights_tab[i];
195         if (chan->qu_sf_idx[i] < 0 || chan->qu_sf_idx[i] > 63) {
196             av_log(avctx, AV_LOG_ERROR,
197                    "SF index out of range: pos=%d, val=%d!\n",
198                    i, chan->qu_sf_idx[i]);
199             return AVERROR_INVALIDDATA;
200         }
201     }
202 
203     return 0;
204 }
205 
206 /**
207  * Unpack vector quantization tables.
208  *
209  * @param[in]    start_val    start value for the unpacked table
210  * @param[in]    shape_vec    ptr to table to unpack
211  * @param[out]   dst          ptr to output array
212  * @param[in]    num_values   number of values to unpack
213  */
unpack_vq_shape(int start_val,const int8_t * shape_vec,int * dst,int num_values)214 static inline void unpack_vq_shape(int start_val, const int8_t *shape_vec,
215                                    int *dst, int num_values)
216 {
217     int i;
218 
219     if (num_values) {
220         dst[0] = dst[1] = dst[2] = start_val;
221         for (i = 3; i < num_values; i++)
222             dst[i] = start_val - shape_vec[atrac3p_qu_num_to_seg[i] - 1];
223     }
224 }
225 
226 #define UNPACK_SF_VQ_SHAPE(gb, dst, num_vals)                            \
227     start_val = get_bits((gb), 6);                                       \
228     unpack_vq_shape(start_val, &atrac3p_sf_shapes[get_bits((gb), 6)][0], \
229                     (dst), (num_vals))
230 
231 /**
232  * Decode word length for each quantization unit of a channel.
233  *
234  * @param[in]     gb            the GetBit context
235  * @param[in,out] ctx           ptr to the channel unit context
236  * @param[in]     ch_num        channel to process
237  * @param[in]     avctx         ptr to the AVCodecContext
238  * @return result code: 0 = OK, otherwise - error code
239  */
decode_channel_wordlen(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,AVCodecContext * avctx)240 static int decode_channel_wordlen(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
241                                   int ch_num, AVCodecContext *avctx)
242 {
243     int i, weight_idx = 0, delta, diff, pos, delta_bits, min_val, flag,
244         ret, start_val;
245     VLC *vlc_tab;
246     Atrac3pChanParams *chan     = &ctx->channels[ch_num];
247     Atrac3pChanParams *ref_chan = &ctx->channels[0];
248 
249     chan->fill_mode = 0;
250 
251     switch (get_bits(gb, 2)) { /* switch according to coding mode */
252     case 0: /* coded using constant number of bits */
253         for (i = 0; i < ctx->num_quant_units; i++)
254             chan->qu_wordlen[i] = get_bits(gb, 3);
255         break;
256     case 1:
257         if (ch_num) {
258             if ((ret = num_coded_units(gb, chan, ctx, avctx)) < 0)
259                 return ret;
260 
261             if (chan->num_coded_vals) {
262                 vlc_tab = &wl_vlc_tabs[get_bits(gb, 2)];
263 
264                 for (i = 0; i < chan->num_coded_vals; i++) {
265                     delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
266                     chan->qu_wordlen[i] = (ref_chan->qu_wordlen[i] + delta) & 7;
267                 }
268             }
269         } else {
270             weight_idx = get_bits(gb, 2);
271             if ((ret = num_coded_units(gb, chan, ctx, avctx)) < 0)
272                 return ret;
273 
274             if (chan->num_coded_vals) {
275                 pos = get_bits(gb, 5);
276                 if (pos > chan->num_coded_vals) {
277                     av_log(avctx, AV_LOG_ERROR,
278                            "WL mode 1: invalid position!\n");
279                     return AVERROR_INVALIDDATA;
280                 }
281 
282                 delta_bits = get_bits(gb, 2);
283                 min_val    = get_bits(gb, 3);
284 
285                 for (i = 0; i < pos; i++)
286                     chan->qu_wordlen[i] = get_bits(gb, 3);
287 
288                 for (i = pos; i < chan->num_coded_vals; i++)
289                     chan->qu_wordlen[i] = (min_val + get_bitsz(gb, delta_bits)) & 7;
290             }
291         }
292         break;
293     case 2:
294         if ((ret = num_coded_units(gb, chan, ctx, avctx)) < 0)
295             return ret;
296 
297         if (ch_num && chan->num_coded_vals) {
298             vlc_tab = &wl_vlc_tabs[get_bits(gb, 2)];
299             delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
300             chan->qu_wordlen[0] = (ref_chan->qu_wordlen[0] + delta) & 7;
301 
302             for (i = 1; i < chan->num_coded_vals; i++) {
303                 diff = ref_chan->qu_wordlen[i] - ref_chan->qu_wordlen[i - 1];
304                 delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
305                 chan->qu_wordlen[i] = (chan->qu_wordlen[i - 1] + diff + delta) & 7;
306             }
307         } else if (chan->num_coded_vals) {
308             flag    = get_bits(gb, 1);
309             vlc_tab = &wl_vlc_tabs[get_bits(gb, 1)];
310 
311             start_val = get_bits(gb, 3);
312             unpack_vq_shape(start_val,
313                             &atrac3p_wl_shapes[start_val][get_bits(gb, 4)][0],
314                             chan->qu_wordlen, chan->num_coded_vals);
315 
316             if (!flag) {
317                 for (i = 0; i < chan->num_coded_vals; i++) {
318                     delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
319                     chan->qu_wordlen[i] = (chan->qu_wordlen[i] + delta) & 7;
320                 }
321             } else {
322                 for (i = 0; i < (chan->num_coded_vals & - 2); i += 2)
323                     if (!get_bits1(gb)) {
324                         chan->qu_wordlen[i]     = (chan->qu_wordlen[i] +
325                                                    get_vlc2(gb, vlc_tab->table,
326                                                             vlc_tab->bits, 1)) & 7;
327                         chan->qu_wordlen[i + 1] = (chan->qu_wordlen[i + 1] +
328                                                    get_vlc2(gb, vlc_tab->table,
329                                                             vlc_tab->bits, 1)) & 7;
330                     }
331 
332                 if (chan->num_coded_vals & 1)
333                     chan->qu_wordlen[i] = (chan->qu_wordlen[i] +
334                                            get_vlc2(gb, vlc_tab->table,
335                                                     vlc_tab->bits, 1)) & 7;
336             }
337         }
338         break;
339     case 3:
340         weight_idx = get_bits(gb, 2);
341         if ((ret = num_coded_units(gb, chan, ctx, avctx)) < 0)
342             return ret;
343 
344         if (chan->num_coded_vals) {
345             vlc_tab = &wl_vlc_tabs[get_bits(gb, 2)];
346 
347             /* first coefficient is coded directly */
348             chan->qu_wordlen[0] = get_bits(gb, 3);
349 
350             for (i = 1; i < chan->num_coded_vals; i++) {
351                 delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
352                 chan->qu_wordlen[i] = (chan->qu_wordlen[i - 1] + delta) & 7;
353             }
354         }
355         break;
356     }
357 
358     if (chan->fill_mode == 2) {
359         for (i = chan->num_coded_vals; i < ctx->num_quant_units; i++)
360             chan->qu_wordlen[i] = ch_num ? get_bits1(gb) : 1;
361     } else if (chan->fill_mode == 3) {
362         pos = ch_num ? chan->num_coded_vals + chan->split_point
363                      : ctx->num_quant_units - chan->split_point;
364         if (pos > FF_ARRAY_ELEMS(chan->qu_wordlen)) {
365             av_log(avctx, AV_LOG_ERROR, "Split point beyond array\n");
366             pos = FF_ARRAY_ELEMS(chan->qu_wordlen);
367         }
368         for (i = chan->num_coded_vals; i < pos; i++)
369             chan->qu_wordlen[i] = 1;
370     }
371 
372     if (weight_idx)
373         return add_wordlen_weights(ctx, chan, weight_idx, avctx);
374 
375     return 0;
376 }
377 
378 /**
379  * Decode scale factor indexes for each quant unit of a channel.
380  *
381  * @param[in]     gb            the GetBit context
382  * @param[in,out] ctx           ptr to the channel unit context
383  * @param[in]     ch_num        channel to process
384  * @param[in]     avctx         ptr to the AVCodecContext
385  * @return result code: 0 = OK, otherwise - error code
386  */
decode_channel_sf_idx(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,AVCodecContext * avctx)387 static int decode_channel_sf_idx(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
388                                  int ch_num, AVCodecContext *avctx)
389 {
390     int i, weight_idx = 0, delta, diff, num_long_vals,
391         delta_bits, min_val, vlc_sel, start_val;
392     VLC *vlc_tab;
393     Atrac3pChanParams *chan     = &ctx->channels[ch_num];
394     Atrac3pChanParams *ref_chan = &ctx->channels[0];
395 
396     switch (get_bits(gb, 2)) { /* switch according to coding mode */
397     case 0: /* coded using constant number of bits */
398         for (i = 0; i < ctx->used_quant_units; i++)
399             chan->qu_sf_idx[i] = get_bits(gb, 6);
400         break;
401     case 1:
402         if (ch_num) {
403             vlc_tab = &sf_vlc_tabs[get_bits(gb, 2)];
404 
405             for (i = 0; i < ctx->used_quant_units; i++) {
406                 delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
407                 chan->qu_sf_idx[i] = (ref_chan->qu_sf_idx[i] + delta) & 0x3F;
408             }
409         } else {
410             weight_idx = get_bits(gb, 2);
411             if (weight_idx == 3) {
412                 UNPACK_SF_VQ_SHAPE(gb, chan->qu_sf_idx, ctx->used_quant_units);
413 
414                 num_long_vals = get_bits(gb, 5);
415                 delta_bits    = get_bits(gb, 2);
416                 min_val       = get_bits(gb, 4) - 7;
417 
418                 for (i = 0; i < num_long_vals; i++)
419                     chan->qu_sf_idx[i] = (chan->qu_sf_idx[i] +
420                                           get_bits(gb, 4) - 7) & 0x3F;
421 
422                 /* all others are: min_val + delta */
423                 for (i = num_long_vals; i < ctx->used_quant_units; i++)
424                     chan->qu_sf_idx[i] = (chan->qu_sf_idx[i] + min_val +
425                                           get_bitsz(gb, delta_bits)) & 0x3F;
426             } else {
427                 num_long_vals = get_bits(gb, 5);
428                 delta_bits    = get_bits(gb, 3);
429                 min_val       = get_bits(gb, 6);
430                 if (num_long_vals > ctx->used_quant_units || delta_bits == 7) {
431                     av_log(avctx, AV_LOG_ERROR,
432                            "SF mode 1: invalid parameters!\n");
433                     return AVERROR_INVALIDDATA;
434                 }
435 
436                 /* read full-precision SF indexes */
437                 for (i = 0; i < num_long_vals; i++)
438                     chan->qu_sf_idx[i] = get_bits(gb, 6);
439 
440                 /* all others are: min_val + delta */
441                 for (i = num_long_vals; i < ctx->used_quant_units; i++)
442                     chan->qu_sf_idx[i] = (min_val +
443                                           get_bitsz(gb, delta_bits)) & 0x3F;
444             }
445         }
446         break;
447     case 2:
448         if (ch_num) {
449             vlc_tab = &sf_vlc_tabs[get_bits(gb, 2)];
450 
451             delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
452             chan->qu_sf_idx[0] = (ref_chan->qu_sf_idx[0] + delta) & 0x3F;
453 
454             for (i = 1; i < ctx->used_quant_units; i++) {
455                 diff  = ref_chan->qu_sf_idx[i] - ref_chan->qu_sf_idx[i - 1];
456                 delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
457                 chan->qu_sf_idx[i] = (chan->qu_sf_idx[i - 1] + diff + delta) & 0x3F;
458             }
459         } else {
460             vlc_tab = &sf_vlc_tabs[get_bits(gb, 2) + 4];
461 
462             UNPACK_SF_VQ_SHAPE(gb, chan->qu_sf_idx, ctx->used_quant_units);
463 
464             for (i = 0; i < ctx->used_quant_units; i++) {
465                 delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
466                 chan->qu_sf_idx[i] = (chan->qu_sf_idx[i] +
467                                       sign_extend(delta, 4)) & 0x3F;
468             }
469         }
470         break;
471     case 3:
472         if (ch_num) {
473             /* copy coefficients from reference channel */
474             for (i = 0; i < ctx->used_quant_units; i++)
475                 chan->qu_sf_idx[i] = ref_chan->qu_sf_idx[i];
476         } else {
477             weight_idx = get_bits(gb, 2);
478             vlc_sel    = get_bits(gb, 2);
479             vlc_tab    = &sf_vlc_tabs[vlc_sel];
480 
481             if (weight_idx == 3) {
482                 vlc_tab = &sf_vlc_tabs[vlc_sel + 4];
483 
484                 UNPACK_SF_VQ_SHAPE(gb, chan->qu_sf_idx, ctx->used_quant_units);
485 
486                 diff               = (get_bits(gb, 4)    + 56)   & 0x3F;
487                 chan->qu_sf_idx[0] = (chan->qu_sf_idx[0] + diff) & 0x3F;
488 
489                 for (i = 1; i < ctx->used_quant_units; i++) {
490                     delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
491                     diff               = (diff + sign_extend(delta, 4)) & 0x3F;
492                     chan->qu_sf_idx[i] = (diff + chan->qu_sf_idx[i])    & 0x3F;
493                 }
494             } else {
495                 /* 1st coefficient is coded directly */
496                 chan->qu_sf_idx[0] = get_bits(gb, 6);
497 
498                 for (i = 1; i < ctx->used_quant_units; i++) {
499                     delta = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
500                     chan->qu_sf_idx[i] = (chan->qu_sf_idx[i - 1] + delta) & 0x3F;
501                 }
502             }
503         }
504         break;
505     }
506 
507     if (weight_idx && weight_idx < 3)
508         return subtract_sf_weights(ctx, chan, weight_idx, avctx);
509 
510     return 0;
511 }
512 
513 /**
514  * Decode word length information for each channel.
515  *
516  * @param[in]     gb            the GetBit context
517  * @param[in,out] ctx           ptr to the channel unit context
518  * @param[in]     num_channels  number of channels to process
519  * @param[in]     avctx         ptr to the AVCodecContext
520  * @return result code: 0 = OK, otherwise - error code
521  */
decode_quant_wordlen(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)522 static int decode_quant_wordlen(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
523                                 int num_channels, AVCodecContext *avctx)
524 {
525     int ch_num, i, ret;
526 
527     for (ch_num = 0; ch_num < num_channels; ch_num++) {
528         memset(ctx->channels[ch_num].qu_wordlen, 0,
529                sizeof(ctx->channels[ch_num].qu_wordlen));
530 
531         if ((ret = decode_channel_wordlen(gb, ctx, ch_num, avctx)) < 0)
532             return ret;
533     }
534 
535     /* scan for last non-zero coeff in both channels and
536      * set number of quant units having coded spectrum */
537     for (i = ctx->num_quant_units - 1; i >= 0; i--)
538         if (ctx->channels[0].qu_wordlen[i] ||
539             (num_channels == 2 && ctx->channels[1].qu_wordlen[i]))
540             break;
541     ctx->used_quant_units = i + 1;
542 
543     return 0;
544 }
545 
546 /**
547  * Decode scale factor indexes for each channel.
548  *
549  * @param[in]     gb            the GetBit context
550  * @param[in,out] ctx           ptr to the channel unit context
551  * @param[in]     num_channels  number of channels to process
552  * @param[in]     avctx         ptr to the AVCodecContext
553  * @return result code: 0 = OK, otherwise - error code
554  */
decode_scale_factors(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)555 static int decode_scale_factors(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
556                                 int num_channels, AVCodecContext *avctx)
557 {
558     int ch_num, ret;
559 
560     if (!ctx->used_quant_units)
561         return 0;
562 
563     for (ch_num = 0; ch_num < num_channels; ch_num++) {
564         memset(ctx->channels[ch_num].qu_sf_idx, 0,
565                sizeof(ctx->channels[ch_num].qu_sf_idx));
566 
567         if ((ret = decode_channel_sf_idx(gb, ctx, ch_num, avctx)) < 0)
568             return ret;
569     }
570 
571     return 0;
572 }
573 
574 /**
575  * Decode number of code table values.
576  *
577  * @param[in]     gb            the GetBit context
578  * @param[in,out] ctx           ptr to the channel unit context
579  * @param[in]     avctx         ptr to the AVCodecContext
580  * @return result code: 0 = OK, otherwise - error code
581  */
get_num_ct_values(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,AVCodecContext * avctx)582 static int get_num_ct_values(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
583                              AVCodecContext *avctx)
584 {
585     int num_coded_vals;
586 
587     if (get_bits1(gb)) {
588         num_coded_vals = get_bits(gb, 5);
589         if (num_coded_vals > ctx->used_quant_units) {
590             av_log(avctx, AV_LOG_ERROR,
591                    "Invalid number of code table indexes: %d!\n", num_coded_vals);
592             return AVERROR_INVALIDDATA;
593         }
594         return num_coded_vals;
595     } else
596         return ctx->used_quant_units;
597 }
598 
599 #define DEC_CT_IDX_COMMON(OP)                                           \
600     num_vals = get_num_ct_values(gb, ctx, avctx);                       \
601     if (num_vals < 0)                                                   \
602         return num_vals;                                                \
603                                                                         \
604     for (i = 0; i < num_vals; i++) {                                    \
605         if (chan->qu_wordlen[i]) {                                      \
606             chan->qu_tab_idx[i] = OP;                                   \
607         } else if (ch_num && ref_chan->qu_wordlen[i])                   \
608             /* get clone master flag */                                 \
609             chan->qu_tab_idx[i] = get_bits1(gb);                        \
610     }
611 
612 #define CODING_DIRECT get_bits(gb, num_bits)
613 
614 #define CODING_VLC get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1)
615 
616 #define CODING_VLC_DELTA                                                \
617     (!i) ? CODING_VLC                                                   \
618          : (pred + get_vlc2(gb, delta_vlc->table,                       \
619                             delta_vlc->bits, 1)) & mask;                \
620     pred = chan->qu_tab_idx[i]
621 
622 #define CODING_VLC_DIFF                                                 \
623     (ref_chan->qu_tab_idx[i] +                                          \
624      get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1)) & mask
625 
626 /**
627  * Decode code table indexes for each quant unit of a channel.
628  *
629  * @param[in]     gb            the GetBit context
630  * @param[in,out] ctx           ptr to the channel unit context
631  * @param[in]     ch_num        channel to process
632  * @param[in]     avctx         ptr to the AVCodecContext
633  * @return result code: 0 = OK, otherwise - error code
634  */
decode_channel_code_tab(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,AVCodecContext * avctx)635 static int decode_channel_code_tab(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
636                                    int ch_num, AVCodecContext *avctx)
637 {
638     int i, num_vals, num_bits, pred;
639     int mask = ctx->use_full_table ? 7 : 3; /* mask for modular arithmetic */
640     VLC *vlc_tab, *delta_vlc;
641     Atrac3pChanParams *chan     = &ctx->channels[ch_num];
642     Atrac3pChanParams *ref_chan = &ctx->channels[0];
643 
644     chan->table_type = get_bits1(gb);
645 
646     switch (get_bits(gb, 2)) { /* switch according to coding mode */
647     case 0: /* directly coded */
648         num_bits = ctx->use_full_table + 2;
649         DEC_CT_IDX_COMMON(CODING_DIRECT);
650         break;
651     case 1: /* entropy-coded */
652         vlc_tab = ctx->use_full_table ? &ct_vlc_tabs[1]
653                                       : ct_vlc_tabs;
654         DEC_CT_IDX_COMMON(CODING_VLC);
655         break;
656     case 2: /* entropy-coded delta */
657         if (ctx->use_full_table) {
658             vlc_tab   = &ct_vlc_tabs[1];
659             delta_vlc = &ct_vlc_tabs[2];
660         } else {
661             vlc_tab   = ct_vlc_tabs;
662             delta_vlc = ct_vlc_tabs;
663         }
664         pred = 0;
665         DEC_CT_IDX_COMMON(CODING_VLC_DELTA);
666         break;
667     case 3: /* entropy-coded difference to master */
668         if (ch_num) {
669             vlc_tab = ctx->use_full_table ? &ct_vlc_tabs[3]
670                                           : ct_vlc_tabs;
671             DEC_CT_IDX_COMMON(CODING_VLC_DIFF);
672         }
673         break;
674     }
675 
676     return 0;
677 }
678 
679 /**
680  * Decode code table indexes for each channel.
681  *
682  * @param[in]     gb            the GetBit context
683  * @param[in,out] ctx           ptr to the channel unit context
684  * @param[in]     num_channels  number of channels to process
685  * @param[in]     avctx         ptr to the AVCodecContext
686  * @return result code: 0 = OK, otherwise - error code
687  */
decode_code_table_indexes(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)688 static int decode_code_table_indexes(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
689                                      int num_channels, AVCodecContext *avctx)
690 {
691     int ch_num, ret;
692 
693     if (!ctx->used_quant_units)
694         return 0;
695 
696     ctx->use_full_table = get_bits1(gb);
697 
698     for (ch_num = 0; ch_num < num_channels; ch_num++) {
699         memset(ctx->channels[ch_num].qu_tab_idx, 0,
700                sizeof(ctx->channels[ch_num].qu_tab_idx));
701 
702         if ((ret = decode_channel_code_tab(gb, ctx, ch_num, avctx)) < 0)
703             return ret;
704     }
705 
706     return 0;
707 }
708 
709 /**
710  * Decode huffman-coded spectral lines for a given quant unit.
711  *
712  * This is a generalized version for all known coding modes.
713  * Its speed can be improved by creating separate functions for each mode.
714  *
715  * @param[in]   gb          the GetBit context
716  * @param[in]   tab         code table telling how to decode spectral lines
717  * @param[in]   vlc_tab     ptr to the huffman table associated with the code table
718  * @param[out]  out         pointer to buffer where decoded data should be stored
719  * @param[in]   num_specs   number of spectral lines to decode
720  */
decode_qu_spectra(GetBitContext * gb,const Atrac3pSpecCodeTab * tab,VLC * vlc_tab,int16_t * out,const int num_specs)721 static void decode_qu_spectra(GetBitContext *gb, const Atrac3pSpecCodeTab *tab,
722                               VLC *vlc_tab, int16_t *out, const int num_specs)
723 {
724     int i, j, pos, cf;
725     int group_size = tab->group_size;
726     int num_coeffs = tab->num_coeffs;
727     int bits       = tab->bits;
728     int is_signed  = tab->is_signed;
729     unsigned val;
730 
731     for (pos = 0; pos < num_specs;) {
732         if (group_size == 1 || get_bits1(gb)) {
733             for (j = 0; j < group_size; j++) {
734                 val = get_vlc2(gb, vlc_tab->table, vlc_tab->bits, 1);
735 
736                 for (i = 0; i < num_coeffs; i++) {
737                     cf = av_mod_uintp2(val, bits);
738                     if (is_signed)
739                         cf = sign_extend(cf, bits);
740                     else if (cf && get_bits1(gb))
741                         cf = -cf;
742 
743                     out[pos++] = cf;
744                     val      >>= bits;
745                 }
746             }
747         } else /* group skipped */
748             pos += group_size * num_coeffs;
749     }
750 }
751 
752 /**
753  * Decode huffman-coded IMDCT spectrum for all channels.
754  *
755  * @param[in]     gb            the GetBit context
756  * @param[in,out] ctx           ptr to the channel unit context
757  * @param[in]     num_channels  number of channels to process
758  * @param[in]     avctx         ptr to the AVCodecContext
759  */
decode_spectrum(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)760 static void decode_spectrum(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
761                             int num_channels, AVCodecContext *avctx)
762 {
763     int i, ch_num, qu, wordlen, codetab, tab_index, num_specs;
764     const Atrac3pSpecCodeTab *tab;
765     Atrac3pChanParams *chan;
766 
767     for (ch_num = 0; ch_num < num_channels; ch_num++) {
768         chan = &ctx->channels[ch_num];
769 
770         memset(chan->spectrum, 0, sizeof(chan->spectrum));
771 
772         /* set power compensation level to disabled */
773         memset(chan->power_levs, ATRAC3P_POWER_COMP_OFF, sizeof(chan->power_levs));
774 
775         for (qu = 0; qu < ctx->used_quant_units; qu++) {
776             num_specs = ff_atrac3p_qu_to_spec_pos[qu + 1] -
777                         ff_atrac3p_qu_to_spec_pos[qu];
778 
779             wordlen = chan->qu_wordlen[qu];
780             codetab = chan->qu_tab_idx[qu];
781             if (wordlen) {
782                 if (!ctx->use_full_table)
783                     codetab = atrac3p_ct_restricted_to_full[chan->table_type][wordlen - 1][codetab];
784 
785                 tab_index = (chan->table_type * 8 + codetab) * 7 + wordlen - 1;
786                 tab       = &atrac3p_spectra_tabs[tab_index];
787 
788                 decode_qu_spectra(gb, tab, &spec_vlc_tabs[tab_index],
789                                   &chan->spectrum[ff_atrac3p_qu_to_spec_pos[qu]],
790                                   num_specs);
791             } else if (ch_num && ctx->channels[0].qu_wordlen[qu] && !codetab) {
792                 /* copy coefficients from master */
793                 memcpy(&chan->spectrum[ff_atrac3p_qu_to_spec_pos[qu]],
794                        &ctx->channels[0].spectrum[ff_atrac3p_qu_to_spec_pos[qu]],
795                        num_specs *
796                        sizeof(chan->spectrum[ff_atrac3p_qu_to_spec_pos[qu]]));
797                 chan->qu_wordlen[qu] = ctx->channels[0].qu_wordlen[qu];
798             }
799         }
800 
801         /* Power compensation levels only present in the bitstream
802          * if there are more than 2 quant units. The lowest two units
803          * correspond to the frequencies 0...351 Hz, whose shouldn't
804          * be affected by the power compensation. */
805         if (ctx->used_quant_units > 2) {
806             num_specs = atrac3p_subband_to_num_powgrps[ctx->num_coded_subbands - 1];
807             for (i = 0; i < num_specs; i++)
808                 chan->power_levs[i] = get_bits(gb, 4);
809         }
810     }
811 }
812 
813 /**
814  * Retrieve specified amount of flag bits from the input bitstream.
815  * The data can be shortened in the case of the following two common conditions:
816  * if all bits are zero then only one signal bit = 0 will be stored,
817  * if all bits are ones then two signal bits = 1,0 will be stored.
818  * Otherwise, all necessary bits will be directly stored
819  * prefixed by two signal bits = 1,1.
820  *
821  * @param[in]   gb              ptr to the GetBitContext
822  * @param[out]  out             where to place decoded flags
823  * @param[in]   num_flags       number of flags to process
824  * @return: 0 = all flag bits are zero, 1 = there is at least one non-zero flag bit
825  */
get_subband_flags(GetBitContext * gb,uint8_t * out,int num_flags)826 static int get_subband_flags(GetBitContext *gb, uint8_t *out, int num_flags)
827 {
828     int i, result;
829 
830     memset(out, 0, num_flags);
831 
832     result = get_bits1(gb);
833     if (result) {
834         if (get_bits1(gb))
835             for (i = 0; i < num_flags; i++)
836                 out[i] = get_bits1(gb);
837         else
838             memset(out, 1, num_flags);
839     }
840 
841     return result;
842 }
843 
844 /**
845  * Decode mdct window shape flags for all channels.
846  *
847  * @param[in]     gb            the GetBit context
848  * @param[in,out] ctx           ptr to the channel unit context
849  * @param[in]     num_channels  number of channels to process
850  */
decode_window_shape(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels)851 static void decode_window_shape(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
852                                 int num_channels)
853 {
854     int ch_num;
855 
856     for (ch_num = 0; ch_num < num_channels; ch_num++)
857         get_subband_flags(gb, ctx->channels[ch_num].wnd_shape,
858                           ctx->num_subbands);
859 }
860 
861 /**
862  * Decode number of gain control points.
863  *
864  * @param[in]     gb              the GetBit context
865  * @param[in,out] ctx             ptr to the channel unit context
866  * @param[in]     ch_num          channel to process
867  * @param[in]     coded_subbands  number of subbands to process
868  * @return result code: 0 = OK, otherwise - error code
869  */
decode_gainc_npoints(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int coded_subbands)870 static int decode_gainc_npoints(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
871                                 int ch_num, int coded_subbands)
872 {
873     int i, delta, delta_bits, min_val;
874     Atrac3pChanParams *chan     = &ctx->channels[ch_num];
875     Atrac3pChanParams *ref_chan = &ctx->channels[0];
876 
877     switch (get_bits(gb, 2)) { /* switch according to coding mode */
878     case 0: /* fixed-length coding */
879         for (i = 0; i < coded_subbands; i++)
880             chan->gain_data[i].num_points = get_bits(gb, 3);
881         break;
882     case 1: /* variable-length coding */
883         for (i = 0; i < coded_subbands; i++)
884             chan->gain_data[i].num_points =
885                 get_vlc2(gb, gain_vlc_tabs[0].table,
886                          gain_vlc_tabs[0].bits, 1);
887         break;
888     case 2:
889         if (ch_num) { /* VLC modulo delta to master channel */
890             for (i = 0; i < coded_subbands; i++) {
891                 delta = get_vlc2(gb, gain_vlc_tabs[1].table,
892                                  gain_vlc_tabs[1].bits, 1);
893                 chan->gain_data[i].num_points =
894                     (ref_chan->gain_data[i].num_points + delta) & 7;
895             }
896         } else { /* VLC modulo delta to previous */
897             chan->gain_data[0].num_points =
898                 get_vlc2(gb, gain_vlc_tabs[0].table,
899                          gain_vlc_tabs[0].bits, 1);
900 
901             for (i = 1; i < coded_subbands; i++) {
902                 delta = get_vlc2(gb, gain_vlc_tabs[1].table,
903                                  gain_vlc_tabs[1].bits, 1);
904                 chan->gain_data[i].num_points =
905                     (chan->gain_data[i - 1].num_points + delta) & 7;
906             }
907         }
908         break;
909     case 3:
910         if (ch_num) { /* copy data from master channel */
911             for (i = 0; i < coded_subbands; i++)
912                 chan->gain_data[i].num_points =
913                     ref_chan->gain_data[i].num_points;
914         } else { /* shorter delta to min */
915             delta_bits = get_bits(gb, 2);
916             min_val    = get_bits(gb, 3);
917 
918             for (i = 0; i < coded_subbands; i++) {
919                 chan->gain_data[i].num_points = min_val + get_bitsz(gb, delta_bits);
920                 if (chan->gain_data[i].num_points > 7)
921                     return AVERROR_INVALIDDATA;
922             }
923         }
924     }
925 
926     return 0;
927 }
928 
929 /**
930  * Implements coding mode 3 (slave) for gain compensation levels.
931  *
932  * @param[out]   dst   ptr to the output array
933  * @param[in]    ref   ptr to the reference channel
934  */
gainc_level_mode3s(AtracGainInfo * dst,AtracGainInfo * ref)935 static inline void gainc_level_mode3s(AtracGainInfo *dst, AtracGainInfo *ref)
936 {
937     int i;
938 
939     for (i = 0; i < dst->num_points; i++)
940         dst->lev_code[i] = (i >= ref->num_points) ? 7 : ref->lev_code[i];
941 }
942 
943 /**
944  * Implements coding mode 1 (master) for gain compensation levels.
945  *
946  * @param[in]     gb     the GetBit context
947  * @param[in]     ctx    ptr to the channel unit context
948  * @param[out]    dst    ptr to the output array
949  */
gainc_level_mode1m(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,AtracGainInfo * dst)950 static inline void gainc_level_mode1m(GetBitContext *gb,
951                                       Atrac3pChanUnitCtx *ctx,
952                                       AtracGainInfo *dst)
953 {
954     int i, delta;
955 
956     if (dst->num_points > 0)
957         dst->lev_code[0] = get_vlc2(gb, gain_vlc_tabs[2].table,
958                                     gain_vlc_tabs[2].bits, 1);
959 
960     for (i = 1; i < dst->num_points; i++) {
961         delta = get_vlc2(gb, gain_vlc_tabs[3].table,
962                          gain_vlc_tabs[3].bits, 1);
963         dst->lev_code[i] = (dst->lev_code[i - 1] + delta) & 0xF;
964     }
965 }
966 
967 /**
968  * Decode level code for each gain control point.
969  *
970  * @param[in]     gb              the GetBit context
971  * @param[in,out] ctx             ptr to the channel unit context
972  * @param[in]     ch_num          channel to process
973  * @param[in]     coded_subbands  number of subbands to process
974  * @return result code: 0 = OK, otherwise - error code
975  */
decode_gainc_levels(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int coded_subbands)976 static int decode_gainc_levels(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
977                                int ch_num, int coded_subbands)
978 {
979     int sb, i, delta, delta_bits, min_val, pred;
980     Atrac3pChanParams *chan     = &ctx->channels[ch_num];
981     Atrac3pChanParams *ref_chan = &ctx->channels[0];
982 
983     switch (get_bits(gb, 2)) { /* switch according to coding mode */
984     case 0: /* fixed-length coding */
985         for (sb = 0; sb < coded_subbands; sb++)
986             for (i = 0; i < chan->gain_data[sb].num_points; i++)
987                 chan->gain_data[sb].lev_code[i] = get_bits(gb, 4);
988         break;
989     case 1:
990         if (ch_num) { /* VLC modulo delta to master channel */
991             for (sb = 0; sb < coded_subbands; sb++)
992                 for (i = 0; i < chan->gain_data[sb].num_points; i++) {
993                     delta = get_vlc2(gb, gain_vlc_tabs[5].table,
994                                      gain_vlc_tabs[5].bits, 1);
995                     pred = (i >= ref_chan->gain_data[sb].num_points)
996                            ? 7 : ref_chan->gain_data[sb].lev_code[i];
997                     chan->gain_data[sb].lev_code[i] = (pred + delta) & 0xF;
998                 }
999         } else { /* VLC modulo delta to previous */
1000             for (sb = 0; sb < coded_subbands; sb++)
1001                 gainc_level_mode1m(gb, ctx, &chan->gain_data[sb]);
1002         }
1003         break;
1004     case 2:
1005         if (ch_num) { /* VLC modulo delta to previous or clone master */
1006             for (sb = 0; sb < coded_subbands; sb++)
1007                 if (chan->gain_data[sb].num_points > 0) {
1008                     if (get_bits1(gb))
1009                         gainc_level_mode1m(gb, ctx, &chan->gain_data[sb]);
1010                     else
1011                         gainc_level_mode3s(&chan->gain_data[sb],
1012                                            &ref_chan->gain_data[sb]);
1013                 }
1014         } else { /* VLC modulo delta to lev_codes of previous subband */
1015             if (chan->gain_data[0].num_points > 0)
1016                 gainc_level_mode1m(gb, ctx, &chan->gain_data[0]);
1017 
1018             for (sb = 1; sb < coded_subbands; sb++)
1019                 for (i = 0; i < chan->gain_data[sb].num_points; i++) {
1020                     delta = get_vlc2(gb, gain_vlc_tabs[4].table,
1021                                      gain_vlc_tabs[4].bits, 1);
1022                     pred = (i >= chan->gain_data[sb - 1].num_points)
1023                            ? 7 : chan->gain_data[sb - 1].lev_code[i];
1024                     chan->gain_data[sb].lev_code[i] = (pred + delta) & 0xF;
1025                 }
1026         }
1027         break;
1028     case 3:
1029         if (ch_num) { /* clone master */
1030             for (sb = 0; sb < coded_subbands; sb++)
1031                 gainc_level_mode3s(&chan->gain_data[sb],
1032                                    &ref_chan->gain_data[sb]);
1033         } else { /* shorter delta to min */
1034             delta_bits = get_bits(gb, 2);
1035             min_val    = get_bits(gb, 4);
1036 
1037             for (sb = 0; sb < coded_subbands; sb++)
1038                 for (i = 0; i < chan->gain_data[sb].num_points; i++) {
1039                     chan->gain_data[sb].lev_code[i] = min_val + get_bitsz(gb, delta_bits);
1040                     if (chan->gain_data[sb].lev_code[i] > 15)
1041                         return AVERROR_INVALIDDATA;
1042                 }
1043         }
1044         break;
1045     }
1046 
1047     return 0;
1048 }
1049 
1050 /**
1051  * Implements coding mode 0 for gain compensation locations.
1052  *
1053  * @param[in]     gb     the GetBit context
1054  * @param[in]     ctx    ptr to the channel unit context
1055  * @param[out]    dst    ptr to the output array
1056  * @param[in]     pos    position of the value to be processed
1057  */
gainc_loc_mode0(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,AtracGainInfo * dst,int pos)1058 static inline void gainc_loc_mode0(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1059                                    AtracGainInfo *dst, int pos)
1060 {
1061     int delta_bits;
1062 
1063     if (!pos || dst->loc_code[pos - 1] < 15)
1064         dst->loc_code[pos] = get_bits(gb, 5);
1065     else if (dst->loc_code[pos - 1] >= 30)
1066         dst->loc_code[pos] = 31;
1067     else {
1068         delta_bits         = av_log2(30 - dst->loc_code[pos - 1]) + 1;
1069         dst->loc_code[pos] = dst->loc_code[pos - 1] +
1070                              get_bits(gb, delta_bits) + 1;
1071     }
1072 }
1073 
1074 /**
1075  * Implements coding mode 1 for gain compensation locations.
1076  *
1077  * @param[in]     gb     the GetBit context
1078  * @param[in]     ctx    ptr to the channel unit context
1079  * @param[out]    dst    ptr to the output array
1080  */
gainc_loc_mode1(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,AtracGainInfo * dst)1081 static inline void gainc_loc_mode1(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1082                                    AtracGainInfo *dst)
1083 {
1084     int i;
1085     VLC *tab;
1086 
1087     if (dst->num_points > 0) {
1088         /* 1st coefficient is stored directly */
1089         dst->loc_code[0] = get_bits(gb, 5);
1090 
1091         for (i = 1; i < dst->num_points; i++) {
1092             /* switch VLC according to the curve direction
1093              * (ascending/descending) */
1094             tab              = (dst->lev_code[i] <= dst->lev_code[i - 1])
1095                                ? &gain_vlc_tabs[7]
1096                                : &gain_vlc_tabs[9];
1097             dst->loc_code[i] = dst->loc_code[i - 1] +
1098                                get_vlc2(gb, tab->table, tab->bits, 1);
1099         }
1100     }
1101 }
1102 
1103 /**
1104  * Decode location code for each gain control point.
1105  *
1106  * @param[in]     gb              the GetBit context
1107  * @param[in,out] ctx             ptr to the channel unit context
1108  * @param[in]     ch_num          channel to process
1109  * @param[in]     coded_subbands  number of subbands to process
1110  * @param[in]     avctx           ptr to the AVCodecContext
1111  * @return result code: 0 = OK, otherwise - error code
1112  */
decode_gainc_loc_codes(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int coded_subbands,AVCodecContext * avctx)1113 static int decode_gainc_loc_codes(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1114                                   int ch_num, int coded_subbands,
1115                                   AVCodecContext *avctx)
1116 {
1117     int sb, i, delta, delta_bits, min_val, pred, more_than_ref;
1118     AtracGainInfo *dst, *ref;
1119     VLC *tab;
1120     Atrac3pChanParams *chan     = &ctx->channels[ch_num];
1121     Atrac3pChanParams *ref_chan = &ctx->channels[0];
1122 
1123     switch (get_bits(gb, 2)) { /* switch according to coding mode */
1124     case 0: /* sequence of numbers in ascending order */
1125         for (sb = 0; sb < coded_subbands; sb++)
1126             for (i = 0; i < chan->gain_data[sb].num_points; i++)
1127                 gainc_loc_mode0(gb, ctx, &chan->gain_data[sb], i);
1128         break;
1129     case 1:
1130         if (ch_num) {
1131             for (sb = 0; sb < coded_subbands; sb++) {
1132                 if (chan->gain_data[sb].num_points <= 0)
1133                     continue;
1134                 dst = &chan->gain_data[sb];
1135                 ref = &ref_chan->gain_data[sb];
1136 
1137                 /* 1st value is vlc-coded modulo delta to master */
1138                 delta = get_vlc2(gb, gain_vlc_tabs[10].table,
1139                                  gain_vlc_tabs[10].bits, 1);
1140                 pred = ref->num_points > 0 ? ref->loc_code[0] : 0;
1141                 dst->loc_code[0] = (pred + delta) & 0x1F;
1142 
1143                 for (i = 1; i < dst->num_points; i++) {
1144                     more_than_ref = i >= ref->num_points;
1145                     if (dst->lev_code[i] > dst->lev_code[i - 1]) {
1146                         /* ascending curve */
1147                         if (more_than_ref) {
1148                             delta =
1149                                 get_vlc2(gb, gain_vlc_tabs[9].table,
1150                                          gain_vlc_tabs[9].bits, 1);
1151                             dst->loc_code[i] = dst->loc_code[i - 1] + delta;
1152                         } else {
1153                             if (get_bits1(gb))
1154                                 gainc_loc_mode0(gb, ctx, dst, i);  // direct coding
1155                             else
1156                                 dst->loc_code[i] = ref->loc_code[i];  // clone master
1157                         }
1158                     } else { /* descending curve */
1159                         tab   = more_than_ref ? &gain_vlc_tabs[7]
1160                                               : &gain_vlc_tabs[10];
1161                         delta = get_vlc2(gb, tab->table, tab->bits, 1);
1162                         if (more_than_ref)
1163                             dst->loc_code[i] = dst->loc_code[i - 1] + delta;
1164                         else
1165                             dst->loc_code[i] = (ref->loc_code[i] + delta) & 0x1F;
1166                     }
1167                 }
1168             }
1169         } else /* VLC delta to previous */
1170             for (sb = 0; sb < coded_subbands; sb++)
1171                 gainc_loc_mode1(gb, ctx, &chan->gain_data[sb]);
1172         break;
1173     case 2:
1174         if (ch_num) {
1175             for (sb = 0; sb < coded_subbands; sb++) {
1176                 if (chan->gain_data[sb].num_points <= 0)
1177                     continue;
1178                 dst = &chan->gain_data[sb];
1179                 ref = &ref_chan->gain_data[sb];
1180                 if (dst->num_points > ref->num_points || get_bits1(gb))
1181                     gainc_loc_mode1(gb, ctx, dst);
1182                 else /* clone master for the whole subband */
1183                     for (i = 0; i < chan->gain_data[sb].num_points; i++)
1184                         dst->loc_code[i] = ref->loc_code[i];
1185             }
1186         } else {
1187             /* data for the first subband is coded directly */
1188             for (i = 0; i < chan->gain_data[0].num_points; i++)
1189                 gainc_loc_mode0(gb, ctx, &chan->gain_data[0], i);
1190 
1191             for (sb = 1; sb < coded_subbands; sb++) {
1192                 if (chan->gain_data[sb].num_points <= 0)
1193                     continue;
1194                 dst = &chan->gain_data[sb];
1195 
1196                 /* 1st value is vlc-coded modulo delta to the corresponding
1197                  * value of the previous subband if any or zero */
1198                 delta = get_vlc2(gb, gain_vlc_tabs[6].table,
1199                                  gain_vlc_tabs[6].bits, 1);
1200                 pred             = dst[-1].num_points > 0
1201                                    ? dst[-1].loc_code[0] : 0;
1202                 dst->loc_code[0] = (pred + delta) & 0x1F;
1203 
1204                 for (i = 1; i < dst->num_points; i++) {
1205                     more_than_ref = i >= dst[-1].num_points;
1206                     /* Select VLC table according to curve direction and
1207                      * presence of prediction. */
1208                     tab = &gain_vlc_tabs[(dst->lev_code[i] > dst->lev_code[i - 1]) *
1209                                                    2 + more_than_ref + 6];
1210                     delta = get_vlc2(gb, tab->table, tab->bits, 1);
1211                     if (more_than_ref)
1212                         dst->loc_code[i] = dst->loc_code[i - 1] + delta;
1213                     else
1214                         dst->loc_code[i] = (dst[-1].loc_code[i] + delta) & 0x1F;
1215                 }
1216             }
1217         }
1218         break;
1219     case 3:
1220         if (ch_num) { /* clone master or direct or direct coding */
1221             for (sb = 0; sb < coded_subbands; sb++)
1222                 for (i = 0; i < chan->gain_data[sb].num_points; i++) {
1223                     if (i >= ref_chan->gain_data[sb].num_points)
1224                         gainc_loc_mode0(gb, ctx, &chan->gain_data[sb], i);
1225                     else
1226                         chan->gain_data[sb].loc_code[i] =
1227                             ref_chan->gain_data[sb].loc_code[i];
1228                 }
1229         } else { /* shorter delta to min */
1230             delta_bits = get_bits(gb, 2) + 1;
1231             min_val    = get_bits(gb, 5);
1232 
1233             for (sb = 0; sb < coded_subbands; sb++)
1234                 for (i = 0; i < chan->gain_data[sb].num_points; i++)
1235                     chan->gain_data[sb].loc_code[i] = min_val + i +
1236                                                       get_bits(gb, delta_bits);
1237         }
1238         break;
1239     }
1240 
1241     /* Validate decoded information */
1242     for (sb = 0; sb < coded_subbands; sb++) {
1243         dst = &chan->gain_data[sb];
1244         for (i = 0; i < chan->gain_data[sb].num_points; i++) {
1245             if (dst->loc_code[i] < 0 || dst->loc_code[i] > 31 ||
1246                 (i && dst->loc_code[i] <= dst->loc_code[i - 1])) {
1247                 av_log(avctx, AV_LOG_ERROR,
1248                        "Invalid gain location: ch=%d, sb=%d, pos=%d, val=%d\n",
1249                        ch_num, sb, i, dst->loc_code[i]);
1250                 return AVERROR_INVALIDDATA;
1251             }
1252         }
1253     }
1254 
1255     return 0;
1256 }
1257 
1258 /**
1259  * Decode gain control data for all channels.
1260  *
1261  * @param[in]     gb            the GetBit context
1262  * @param[in,out] ctx           ptr to the channel unit context
1263  * @param[in]     num_channels  number of channels to process
1264  * @param[in]     avctx         ptr to the AVCodecContext
1265  * @return result code: 0 = OK, otherwise - error code
1266  */
decode_gainc_data(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)1267 static int decode_gainc_data(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1268                              int num_channels, AVCodecContext *avctx)
1269 {
1270     int ch_num, coded_subbands, sb, ret;
1271 
1272     for (ch_num = 0; ch_num < num_channels; ch_num++) {
1273         memset(ctx->channels[ch_num].gain_data, 0,
1274                sizeof(*ctx->channels[ch_num].gain_data) * ATRAC3P_SUBBANDS);
1275 
1276         if (get_bits1(gb)) { /* gain control data present? */
1277             coded_subbands = get_bits(gb, 4) + 1;
1278             if (get_bits1(gb)) /* is high band gain data replication on? */
1279                 ctx->channels[ch_num].num_gain_subbands = get_bits(gb, 4) + 1;
1280             else
1281                 ctx->channels[ch_num].num_gain_subbands = coded_subbands;
1282 
1283             if ((ret = decode_gainc_npoints(gb, ctx, ch_num, coded_subbands)) < 0 ||
1284                 (ret = decode_gainc_levels(gb, ctx, ch_num, coded_subbands))  < 0 ||
1285                 (ret = decode_gainc_loc_codes(gb, ctx, ch_num, coded_subbands, avctx)) < 0)
1286                 return ret;
1287 
1288             if (coded_subbands > 0) { /* propagate gain data if requested */
1289                 for (sb = coded_subbands; sb < ctx->channels[ch_num].num_gain_subbands; sb++)
1290                     ctx->channels[ch_num].gain_data[sb] =
1291                         ctx->channels[ch_num].gain_data[sb - 1];
1292             }
1293         } else {
1294             ctx->channels[ch_num].num_gain_subbands = 0;
1295         }
1296     }
1297 
1298     return 0;
1299 }
1300 
1301 /**
1302  * Decode envelope for all tones of a channel.
1303  *
1304  * @param[in]     gb                the GetBit context
1305  * @param[in,out] ctx               ptr to the channel unit context
1306  * @param[in]     ch_num            channel to process
1307  * @param[in]     band_has_tones    ptr to an array of per-band-flags:
1308  *                                  1 - tone data present
1309  */
decode_tones_envelope(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int band_has_tones[])1310 static void decode_tones_envelope(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1311                                   int ch_num, int band_has_tones[])
1312 {
1313     int sb;
1314     Atrac3pWavesData *dst = ctx->channels[ch_num].tones_info;
1315     Atrac3pWavesData *ref = ctx->channels[0].tones_info;
1316 
1317     if (!ch_num || !get_bits1(gb)) { /* mode 0: fixed-length coding */
1318         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1319             if (!band_has_tones[sb])
1320                 continue;
1321             dst[sb].pend_env.has_start_point = get_bits1(gb);
1322             dst[sb].pend_env.start_pos       = dst[sb].pend_env.has_start_point
1323                                                ? get_bits(gb, 5) : -1;
1324             dst[sb].pend_env.has_stop_point  = get_bits1(gb);
1325             dst[sb].pend_env.stop_pos        = dst[sb].pend_env.has_stop_point
1326                                                ? get_bits(gb, 5) : 32;
1327         }
1328     } else { /* mode 1(slave only): copy master */
1329         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1330             if (!band_has_tones[sb])
1331                 continue;
1332             dst[sb].pend_env.has_start_point = ref[sb].pend_env.has_start_point;
1333             dst[sb].pend_env.has_stop_point  = ref[sb].pend_env.has_stop_point;
1334             dst[sb].pend_env.start_pos       = ref[sb].pend_env.start_pos;
1335             dst[sb].pend_env.stop_pos        = ref[sb].pend_env.stop_pos;
1336         }
1337     }
1338 }
1339 
1340 /**
1341  * Decode number of tones for each subband of a channel.
1342  *
1343  * @param[in]     gb                the GetBit context
1344  * @param[in,out] ctx               ptr to the channel unit context
1345  * @param[in]     ch_num            channel to process
1346  * @param[in]     band_has_tones    ptr to an array of per-band-flags:
1347  *                                  1 - tone data present
1348  * @param[in]     avctx             ptr to the AVCodecContext
1349  * @return result code: 0 = OK, otherwise - error code
1350  */
decode_band_numwavs(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int band_has_tones[],AVCodecContext * avctx)1351 static int decode_band_numwavs(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1352                                int ch_num, int band_has_tones[],
1353                                AVCodecContext *avctx)
1354 {
1355     int mode, sb, delta;
1356     Atrac3pWavesData *dst = ctx->channels[ch_num].tones_info;
1357     Atrac3pWavesData *ref = ctx->channels[0].tones_info;
1358 
1359     mode = get_bits(gb, ch_num + 1);
1360     switch (mode) {
1361     case 0: /** fixed-length coding */
1362         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++)
1363             if (band_has_tones[sb])
1364                 dst[sb].num_wavs = get_bits(gb, 4);
1365         break;
1366     case 1: /** variable-length coding */
1367         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++)
1368             if (band_has_tones[sb])
1369                 dst[sb].num_wavs =
1370                     get_vlc2(gb, tone_vlc_tabs[1].table,
1371                              tone_vlc_tabs[1].bits, 1);
1372         break;
1373     case 2: /** VLC modulo delta to master (slave only) */
1374         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++)
1375             if (band_has_tones[sb]) {
1376                 delta = get_vlc2(gb, tone_vlc_tabs[2].table,
1377                                  tone_vlc_tabs[2].bits, 1);
1378                 delta = sign_extend(delta, 3);
1379                 dst[sb].num_wavs = (ref[sb].num_wavs + delta) & 0xF;
1380             }
1381         break;
1382     case 3: /** copy master (slave only) */
1383         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++)
1384             if (band_has_tones[sb])
1385                 dst[sb].num_wavs = ref[sb].num_wavs;
1386         break;
1387     }
1388 
1389     /** initialize start tone index for each subband */
1390     for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++)
1391         if (band_has_tones[sb]) {
1392             if (ctx->waves_info->tones_index + dst[sb].num_wavs > 48) {
1393                 av_log(avctx, AV_LOG_ERROR,
1394                        "Too many tones: %d (max. 48), frame: %d!\n",
1395                        ctx->waves_info->tones_index + dst[sb].num_wavs,
1396                        avctx->frame_number);
1397                 return AVERROR_INVALIDDATA;
1398             }
1399             dst[sb].start_index           = ctx->waves_info->tones_index;
1400             ctx->waves_info->tones_index += dst[sb].num_wavs;
1401         }
1402 
1403     return 0;
1404 }
1405 
1406 /**
1407  * Decode frequency information for each subband of a channel.
1408  *
1409  * @param[in]     gb                the GetBit context
1410  * @param[in,out] ctx               ptr to the channel unit context
1411  * @param[in]     ch_num            channel to process
1412  * @param[in]     band_has_tones    ptr to an array of per-band-flags:
1413  *                                  1 - tone data present
1414  */
decode_tones_frequency(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int band_has_tones[])1415 static void decode_tones_frequency(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1416                                    int ch_num, int band_has_tones[])
1417 {
1418     int sb, i, direction, nbits, pred, delta;
1419     Atrac3pWaveParam *iwav, *owav;
1420     Atrac3pWavesData *dst = ctx->channels[ch_num].tones_info;
1421     Atrac3pWavesData *ref = ctx->channels[0].tones_info;
1422 
1423     if (!ch_num || !get_bits1(gb)) { /* mode 0: fixed-length coding */
1424         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1425             if (!band_has_tones[sb] || !dst[sb].num_wavs)
1426                 continue;
1427             iwav      = &ctx->waves_info->waves[dst[sb].start_index];
1428             direction = (dst[sb].num_wavs > 1) ? get_bits1(gb) : 0;
1429             if (direction) { /** packed numbers in descending order */
1430                 if (dst[sb].num_wavs)
1431                     iwav[dst[sb].num_wavs - 1].freq_index = get_bits(gb, 10);
1432                 for (i = dst[sb].num_wavs - 2; i >= 0 ; i--) {
1433                     nbits = av_log2(iwav[i+1].freq_index) + 1;
1434                     iwav[i].freq_index = get_bits(gb, nbits);
1435                 }
1436             } else { /** packed numbers in ascending order */
1437                 for (i = 0; i < dst[sb].num_wavs; i++) {
1438                     if (!i || iwav[i - 1].freq_index < 512)
1439                         iwav[i].freq_index = get_bits(gb, 10);
1440                     else {
1441                         nbits = av_log2(1023 - iwav[i - 1].freq_index) + 1;
1442                         iwav[i].freq_index = get_bits(gb, nbits) +
1443                                              1024 - (1 << nbits);
1444                     }
1445                 }
1446             }
1447         }
1448     } else { /* mode 1: VLC modulo delta to master (slave only) */
1449         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1450             if (!band_has_tones[sb] || !dst[sb].num_wavs)
1451                 continue;
1452             iwav = &ctx->waves_info->waves[ref[sb].start_index];
1453             owav = &ctx->waves_info->waves[dst[sb].start_index];
1454             for (i = 0; i < dst[sb].num_wavs; i++) {
1455                 delta = get_vlc2(gb, tone_vlc_tabs[6].table,
1456                                  tone_vlc_tabs[6].bits, 1);
1457                 delta = sign_extend(delta, 8);
1458                 pred  = (i < ref[sb].num_wavs) ? iwav[i].freq_index :
1459                         (ref[sb].num_wavs ? iwav[ref[sb].num_wavs - 1].freq_index : 0);
1460                 owav[i].freq_index = (pred + delta) & 0x3FF;
1461             }
1462         }
1463     }
1464 }
1465 
1466 /**
1467  * Decode amplitude information for each subband of a channel.
1468  *
1469  * @param[in]     gb                the GetBit context
1470  * @param[in,out] ctx               ptr to the channel unit context
1471  * @param[in]     ch_num            channel to process
1472  * @param[in]     band_has_tones    ptr to an array of per-band-flags:
1473  *                                  1 - tone data present
1474  */
decode_tones_amplitude(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int band_has_tones[])1475 static void decode_tones_amplitude(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1476                                    int ch_num, int band_has_tones[])
1477 {
1478     int mode, sb, j, i, diff, maxdiff, fi, delta, pred;
1479     Atrac3pWaveParam *wsrc, *wref;
1480     int refwaves[48] = { 0 };
1481     Atrac3pWavesData *dst = ctx->channels[ch_num].tones_info;
1482     Atrac3pWavesData *ref = ctx->channels[0].tones_info;
1483 
1484     if (ch_num) {
1485         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1486             if (!band_has_tones[sb] || !dst[sb].num_wavs)
1487                 continue;
1488             wsrc = &ctx->waves_info->waves[dst[sb].start_index];
1489             wref = &ctx->waves_info->waves[ref[sb].start_index];
1490             for (j = 0; j < dst[sb].num_wavs; j++) {
1491                 for (i = 0, fi = 0, maxdiff = 1024; i < ref[sb].num_wavs; i++) {
1492                     diff = FFABS(wsrc[j].freq_index - wref[i].freq_index);
1493                     if (diff < maxdiff) {
1494                         maxdiff = diff;
1495                         fi      = i;
1496                     }
1497                 }
1498 
1499                 if (maxdiff < 8)
1500                     refwaves[dst[sb].start_index + j] = fi + ref[sb].start_index;
1501                 else if (j < ref[sb].num_wavs)
1502                     refwaves[dst[sb].start_index + j] = j + ref[sb].start_index;
1503                 else
1504                     refwaves[dst[sb].start_index + j] = -1;
1505             }
1506         }
1507     }
1508 
1509     mode = get_bits(gb, ch_num + 1);
1510 
1511     switch (mode) {
1512     case 0: /** fixed-length coding */
1513         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1514             if (!band_has_tones[sb] || !dst[sb].num_wavs)
1515                 continue;
1516             if (ctx->waves_info->amplitude_mode)
1517                 for (i = 0; i < dst[sb].num_wavs; i++)
1518                     ctx->waves_info->waves[dst[sb].start_index + i].amp_sf = get_bits(gb, 6);
1519             else
1520                 ctx->waves_info->waves[dst[sb].start_index].amp_sf = get_bits(gb, 6);
1521         }
1522         break;
1523     case 1: /** min + VLC delta */
1524         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1525             if (!band_has_tones[sb] || !dst[sb].num_wavs)
1526                 continue;
1527             if (ctx->waves_info->amplitude_mode)
1528                 for (i = 0; i < dst[sb].num_wavs; i++)
1529                     ctx->waves_info->waves[dst[sb].start_index + i].amp_sf =
1530                         get_vlc2(gb, tone_vlc_tabs[3].table,
1531                                  tone_vlc_tabs[3].bits, 1) + 20;
1532             else
1533                 ctx->waves_info->waves[dst[sb].start_index].amp_sf =
1534                     get_vlc2(gb, tone_vlc_tabs[4].table,
1535                              tone_vlc_tabs[4].bits, 1) + 24;
1536         }
1537         break;
1538     case 2: /** VLC modulo delta to master (slave only) */
1539         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1540             if (!band_has_tones[sb] || !dst[sb].num_wavs)
1541                 continue;
1542             for (i = 0; i < dst[sb].num_wavs; i++) {
1543                 delta = get_vlc2(gb, tone_vlc_tabs[5].table,
1544                                  tone_vlc_tabs[5].bits, 1);
1545                 delta = sign_extend(delta, 5);
1546                 pred  = refwaves[dst[sb].start_index + i] >= 0 ?
1547                         ctx->waves_info->waves[refwaves[dst[sb].start_index + i]].amp_sf : 34;
1548                 ctx->waves_info->waves[dst[sb].start_index + i].amp_sf = (pred + delta) & 0x3F;
1549             }
1550         }
1551         break;
1552     case 3: /** clone master (slave only) */
1553         for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1554             if (!band_has_tones[sb])
1555                 continue;
1556             for (i = 0; i < dst[sb].num_wavs; i++)
1557                 ctx->waves_info->waves[dst[sb].start_index + i].amp_sf =
1558                     refwaves[dst[sb].start_index + i] >= 0
1559                     ? ctx->waves_info->waves[refwaves[dst[sb].start_index + i]].amp_sf
1560                     : 32;
1561         }
1562         break;
1563     }
1564 }
1565 
1566 /**
1567  * Decode phase information for each subband of a channel.
1568  *
1569  * @param[in]     gb                the GetBit context
1570  * @param[in,out] ctx               ptr to the channel unit context
1571  * @param[in]     ch_num            channel to process
1572  * @param[in]     band_has_tones    ptr to an array of per-band-flags:
1573  *                                  1 - tone data present
1574  */
decode_tones_phase(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int ch_num,int band_has_tones[])1575 static void decode_tones_phase(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1576                                int ch_num, int band_has_tones[])
1577 {
1578     int sb, i;
1579     Atrac3pWaveParam *wparam;
1580     Atrac3pWavesData *dst = ctx->channels[ch_num].tones_info;
1581 
1582     for (sb = 0; sb < ctx->waves_info->num_tone_bands; sb++) {
1583         if (!band_has_tones[sb])
1584             continue;
1585         wparam = &ctx->waves_info->waves[dst[sb].start_index];
1586         for (i = 0; i < dst[sb].num_wavs; i++)
1587             wparam[i].phase_index = get_bits(gb, 5);
1588     }
1589 }
1590 
1591 /**
1592  * Decode tones info for all channels.
1593  *
1594  * @param[in]     gb            the GetBit context
1595  * @param[in,out] ctx           ptr to the channel unit context
1596  * @param[in]     num_channels  number of channels to process
1597  * @param[in]     avctx         ptr to the AVCodecContext
1598  * @return result code: 0 = OK, otherwise - error code
1599  */
decode_tones_info(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)1600 static int decode_tones_info(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1601                              int num_channels, AVCodecContext *avctx)
1602 {
1603     int ch_num, i, ret;
1604     int band_has_tones[16];
1605 
1606     for (ch_num = 0; ch_num < num_channels; ch_num++)
1607         memset(ctx->channels[ch_num].tones_info, 0,
1608                sizeof(*ctx->channels[ch_num].tones_info) * ATRAC3P_SUBBANDS);
1609 
1610     ctx->waves_info->tones_present = get_bits1(gb);
1611     if (!ctx->waves_info->tones_present)
1612         return 0;
1613 
1614     memset(ctx->waves_info->waves, 0, sizeof(ctx->waves_info->waves));
1615 
1616     ctx->waves_info->amplitude_mode = get_bits1(gb);
1617     if (!ctx->waves_info->amplitude_mode) {
1618         avpriv_report_missing_feature(avctx, "GHA amplitude mode 0");
1619         return AVERROR_PATCHWELCOME;
1620     }
1621 
1622     ctx->waves_info->num_tone_bands =
1623         get_vlc2(gb, tone_vlc_tabs[0].table,
1624                  tone_vlc_tabs[0].bits, 1) + 1;
1625 
1626     if (num_channels == 2) {
1627         get_subband_flags(gb, ctx->waves_info->tone_sharing, ctx->waves_info->num_tone_bands);
1628         get_subband_flags(gb, ctx->waves_info->tone_master,  ctx->waves_info->num_tone_bands);
1629         get_subband_flags(gb, ctx->waves_info->invert_phase, ctx->waves_info->num_tone_bands);
1630     }
1631 
1632     ctx->waves_info->tones_index = 0;
1633 
1634     for (ch_num = 0; ch_num < num_channels; ch_num++) {
1635         for (i = 0; i < ctx->waves_info->num_tone_bands; i++)
1636             band_has_tones[i] = !ch_num ? 1 : !ctx->waves_info->tone_sharing[i];
1637 
1638         decode_tones_envelope(gb, ctx, ch_num, band_has_tones);
1639         if ((ret = decode_band_numwavs(gb, ctx, ch_num, band_has_tones,
1640                                        avctx)) < 0)
1641             return ret;
1642 
1643         decode_tones_frequency(gb, ctx, ch_num, band_has_tones);
1644         decode_tones_amplitude(gb, ctx, ch_num, band_has_tones);
1645         decode_tones_phase(gb, ctx, ch_num, band_has_tones);
1646     }
1647 
1648     if (num_channels == 2) {
1649         for (i = 0; i < ctx->waves_info->num_tone_bands; i++) {
1650             if (ctx->waves_info->tone_sharing[i])
1651                 ctx->channels[1].tones_info[i] = ctx->channels[0].tones_info[i];
1652 
1653             if (ctx->waves_info->tone_master[i])
1654                 FFSWAP(Atrac3pWavesData, ctx->channels[0].tones_info[i],
1655                        ctx->channels[1].tones_info[i]);
1656         }
1657     }
1658 
1659     return 0;
1660 }
1661 
ff_atrac3p_decode_channel_unit(GetBitContext * gb,Atrac3pChanUnitCtx * ctx,int num_channels,AVCodecContext * avctx)1662 int ff_atrac3p_decode_channel_unit(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
1663                                    int num_channels, AVCodecContext *avctx)
1664 {
1665     int ret;
1666 
1667     /* parse sound header */
1668     ctx->num_quant_units = get_bits(gb, 5) + 1;
1669     if (ctx->num_quant_units > 28 && ctx->num_quant_units < 32) {
1670         av_log(avctx, AV_LOG_ERROR,
1671                "Invalid number of quantization units: %d!\n",
1672                ctx->num_quant_units);
1673         return AVERROR_INVALIDDATA;
1674     }
1675 
1676     ctx->mute_flag = get_bits1(gb);
1677 
1678     /* decode various sound parameters */
1679     if ((ret = decode_quant_wordlen(gb, ctx, num_channels, avctx)) < 0)
1680         return ret;
1681 
1682     ctx->num_subbands       = atrac3p_qu_to_subband[ctx->num_quant_units - 1] + 1;
1683     ctx->num_coded_subbands = ctx->used_quant_units
1684                               ? atrac3p_qu_to_subband[ctx->used_quant_units - 1] + 1
1685                               : 0;
1686 
1687     if ((ret = decode_scale_factors(gb, ctx, num_channels, avctx)) < 0)
1688         return ret;
1689 
1690     if ((ret = decode_code_table_indexes(gb, ctx, num_channels, avctx)) < 0)
1691         return ret;
1692 
1693     decode_spectrum(gb, ctx, num_channels, avctx);
1694 
1695     if (num_channels == 2) {
1696         get_subband_flags(gb, ctx->swap_channels, ctx->num_coded_subbands);
1697         get_subband_flags(gb, ctx->negate_coeffs, ctx->num_coded_subbands);
1698     }
1699 
1700     decode_window_shape(gb, ctx, num_channels);
1701 
1702     if ((ret = decode_gainc_data(gb, ctx, num_channels, avctx)) < 0)
1703         return ret;
1704 
1705     if ((ret = decode_tones_info(gb, ctx, num_channels, avctx)) < 0)
1706         return ret;
1707 
1708     /* decode global noise info */
1709     ctx->noise_present = get_bits1(gb);
1710     if (ctx->noise_present) {
1711         ctx->noise_level_index = get_bits(gb, 4);
1712         ctx->noise_table_index = get_bits(gb, 4);
1713     }
1714 
1715     return 0;
1716 }
1717