1 /*
2 * MLP decoder
3 * Copyright (c) 2007-2008 Ian Caulfield
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * MLP decoder
25 */
26
27 #include <stdint.h>
28
29 #include "avcodec.h"
30 #include "libavutil/internal.h"
31 #include "libavutil/intreadwrite.h"
32 #include "libavutil/channel_layout.h"
33 #include "get_bits.h"
34 #include "internal.h"
35 #include "libavutil/crc.h"
36 #include "parser.h"
37 #include "mlp_parse.h"
38 #include "mlpdsp.h"
39 #include "mlp.h"
40 #include "config.h"
41
42 /** number of bits used for VLC lookup - longest Huffman code is 9 */
43 #if ARCH_ARM
44 #define VLC_BITS 5
45 #define VLC_STATIC_SIZE 64
46 #else
47 #define VLC_BITS 9
48 #define VLC_STATIC_SIZE 512
49 #endif
50
51 typedef struct SubStream {
52 /// Set if a valid restart header has been read. Otherwise the substream cannot be decoded.
53 uint8_t restart_seen;
54
55 //@{
56 /** restart header data */
57 /// The type of noise to be used in the rematrix stage.
58 uint16_t noise_type;
59
60 /// The index of the first channel coded in this substream.
61 uint8_t min_channel;
62 /// The index of the last channel coded in this substream.
63 uint8_t max_channel;
64 /// The number of channels input into the rematrix stage.
65 uint8_t max_matrix_channel;
66 /// For each channel output by the matrix, the output channel to map it to
67 uint8_t ch_assign[MAX_CHANNELS];
68 /// The channel layout for this substream
69 uint64_t mask;
70 /// The matrix encoding mode for this substream
71 enum AVMatrixEncoding matrix_encoding;
72
73 /// Channel coding parameters for channels in the substream
74 ChannelParams channel_params[MAX_CHANNELS];
75
76 /// The left shift applied to random noise in 0x31ea substreams.
77 uint8_t noise_shift;
78 /// The current seed value for the pseudorandom noise generator(s).
79 uint32_t noisegen_seed;
80
81 /// Set if the substream contains extra info to check the size of VLC blocks.
82 uint8_t data_check_present;
83
84 /// Bitmask of which parameter sets are conveyed in a decoding parameter block.
85 uint8_t param_presence_flags;
86 #define PARAM_BLOCKSIZE (1 << 7)
87 #define PARAM_MATRIX (1 << 6)
88 #define PARAM_OUTSHIFT (1 << 5)
89 #define PARAM_QUANTSTEP (1 << 4)
90 #define PARAM_FIR (1 << 3)
91 #define PARAM_IIR (1 << 2)
92 #define PARAM_HUFFOFFSET (1 << 1)
93 #define PARAM_PRESENCE (1 << 0)
94 //@}
95
96 //@{
97 /** matrix data */
98
99 /// Number of matrices to be applied.
100 uint8_t num_primitive_matrices;
101
102 /// matrix output channel
103 uint8_t matrix_out_ch[MAX_MATRICES];
104
105 /// Whether the LSBs of the matrix output are encoded in the bitstream.
106 uint8_t lsb_bypass[MAX_MATRICES];
107 /// Matrix coefficients, stored as 2.14 fixed point.
108 DECLARE_ALIGNED(32, int32_t, matrix_coeff)[MAX_MATRICES][MAX_CHANNELS];
109 /// Left shift to apply to noise values in 0x31eb substreams.
110 uint8_t matrix_noise_shift[MAX_MATRICES];
111 //@}
112
113 /// Left shift to apply to Huffman-decoded residuals.
114 uint8_t quant_step_size[MAX_CHANNELS];
115
116 /// number of PCM samples in current audio block
117 uint16_t blocksize;
118 /// Number of PCM samples decoded so far in this frame.
119 uint16_t blockpos;
120
121 /// Left shift to apply to decoded PCM values to get final 24-bit output.
122 int8_t output_shift[MAX_CHANNELS];
123
124 /// Running XOR of all output samples.
125 int32_t lossless_check_data;
126
127 } SubStream;
128
129 typedef struct MLPDecodeContext {
130 AVCodecContext *avctx;
131
132 /// Current access unit being read has a major sync.
133 int is_major_sync_unit;
134
135 /// Size of the major sync unit, in bytes
136 int major_sync_header_size;
137
138 /// Set if a valid major sync block has been read. Otherwise no decoding is possible.
139 uint8_t params_valid;
140
141 /// Number of substreams contained within this stream.
142 uint8_t num_substreams;
143
144 /// Index of the last substream to decode - further substreams are skipped.
145 uint8_t max_decoded_substream;
146
147 /// Stream needs channel reordering to comply with FFmpeg's channel order
148 uint8_t needs_reordering;
149
150 /// number of PCM samples contained in each frame
151 int access_unit_size;
152 /// next power of two above the number of samples in each frame
153 int access_unit_size_pow2;
154
155 SubStream substream[MAX_SUBSTREAMS];
156
157 int matrix_changed;
158 int filter_changed[MAX_CHANNELS][NUM_FILTERS];
159
160 int8_t noise_buffer[MAX_BLOCKSIZE_POW2];
161 int8_t bypassed_lsbs[MAX_BLOCKSIZE][MAX_CHANNELS];
162 DECLARE_ALIGNED(32, int32_t, sample_buffer)[MAX_BLOCKSIZE][MAX_CHANNELS];
163
164 MLPDSPContext dsp;
165 } MLPDecodeContext;
166
167 static const uint64_t thd_channel_order[] = {
168 AV_CH_FRONT_LEFT, AV_CH_FRONT_RIGHT, // LR
169 AV_CH_FRONT_CENTER, // C
170 AV_CH_LOW_FREQUENCY, // LFE
171 AV_CH_SIDE_LEFT, AV_CH_SIDE_RIGHT, // LRs
172 AV_CH_TOP_FRONT_LEFT, AV_CH_TOP_FRONT_RIGHT, // LRvh
173 AV_CH_FRONT_LEFT_OF_CENTER, AV_CH_FRONT_RIGHT_OF_CENTER, // LRc
174 AV_CH_BACK_LEFT, AV_CH_BACK_RIGHT, // LRrs
175 AV_CH_BACK_CENTER, // Cs
176 AV_CH_TOP_CENTER, // Ts
177 AV_CH_SURROUND_DIRECT_LEFT, AV_CH_SURROUND_DIRECT_RIGHT, // LRsd
178 AV_CH_WIDE_LEFT, AV_CH_WIDE_RIGHT, // LRw
179 AV_CH_TOP_FRONT_CENTER, // Cvh
180 AV_CH_LOW_FREQUENCY_2, // LFE2
181 };
182
mlp_channel_layout_subset(uint64_t channel_layout,uint64_t mask)183 static int mlp_channel_layout_subset(uint64_t channel_layout, uint64_t mask)
184 {
185 return channel_layout && ((channel_layout & mask) == channel_layout);
186 }
187
thd_channel_layout_extract_channel(uint64_t channel_layout,int index)188 static uint64_t thd_channel_layout_extract_channel(uint64_t channel_layout,
189 int index)
190 {
191 int i;
192
193 if (av_get_channel_layout_nb_channels(channel_layout) <= index)
194 return 0;
195
196 for (i = 0; i < FF_ARRAY_ELEMS(thd_channel_order); i++)
197 if (channel_layout & thd_channel_order[i] && !index--)
198 return thd_channel_order[i];
199 return 0;
200 }
201
202 static VLC huff_vlc[3];
203
204 /** Initialize static data, constant between all invocations of the codec. */
205
init_static(void)206 static av_cold void init_static(void)
207 {
208 if (!huff_vlc[0].bits) {
209 INIT_VLC_STATIC(&huff_vlc[0], VLC_BITS, 18,
210 &ff_mlp_huffman_tables[0][0][1], 2, 1,
211 &ff_mlp_huffman_tables[0][0][0], 2, 1, VLC_STATIC_SIZE);
212 INIT_VLC_STATIC(&huff_vlc[1], VLC_BITS, 16,
213 &ff_mlp_huffman_tables[1][0][1], 2, 1,
214 &ff_mlp_huffman_tables[1][0][0], 2, 1, VLC_STATIC_SIZE);
215 INIT_VLC_STATIC(&huff_vlc[2], VLC_BITS, 15,
216 &ff_mlp_huffman_tables[2][0][1], 2, 1,
217 &ff_mlp_huffman_tables[2][0][0], 2, 1, VLC_STATIC_SIZE);
218 }
219
220 ff_mlp_init_crc();
221 }
222
calculate_sign_huff(MLPDecodeContext * m,unsigned int substr,unsigned int ch)223 static inline int32_t calculate_sign_huff(MLPDecodeContext *m,
224 unsigned int substr, unsigned int ch)
225 {
226 SubStream *s = &m->substream[substr];
227 ChannelParams *cp = &s->channel_params[ch];
228 int lsb_bits = cp->huff_lsbs - s->quant_step_size[ch];
229 int sign_shift = lsb_bits + (cp->codebook ? 2 - cp->codebook : -1);
230 int32_t sign_huff_offset = cp->huff_offset;
231
232 if (cp->codebook > 0)
233 sign_huff_offset -= 7 << lsb_bits;
234
235 if (sign_shift >= 0)
236 sign_huff_offset -= 1 << sign_shift;
237
238 return sign_huff_offset;
239 }
240
241 /** Read a sample, consisting of either, both or neither of entropy-coded MSBs
242 * and plain LSBs. */
243
read_huff_channels(MLPDecodeContext * m,GetBitContext * gbp,unsigned int substr,unsigned int pos)244 static inline int read_huff_channels(MLPDecodeContext *m, GetBitContext *gbp,
245 unsigned int substr, unsigned int pos)
246 {
247 SubStream *s = &m->substream[substr];
248 unsigned int mat, channel;
249
250 for (mat = 0; mat < s->num_primitive_matrices; mat++)
251 if (s->lsb_bypass[mat])
252 m->bypassed_lsbs[pos + s->blockpos][mat] = get_bits1(gbp);
253
254 for (channel = s->min_channel; channel <= s->max_channel; channel++) {
255 ChannelParams *cp = &s->channel_params[channel];
256 int codebook = cp->codebook;
257 int quant_step_size = s->quant_step_size[channel];
258 int lsb_bits = cp->huff_lsbs - quant_step_size;
259 int result = 0;
260
261 if (codebook > 0)
262 result = get_vlc2(gbp, huff_vlc[codebook-1].table,
263 VLC_BITS, (9 + VLC_BITS - 1) / VLC_BITS);
264
265 if (result < 0)
266 return AVERROR_INVALIDDATA;
267
268 if (lsb_bits > 0)
269 result = (result << lsb_bits) + get_bits_long(gbp, lsb_bits);
270
271 result += cp->sign_huff_offset;
272 result *= 1 << quant_step_size;
273
274 m->sample_buffer[pos + s->blockpos][channel] = result;
275 }
276
277 return 0;
278 }
279
mlp_decode_init(AVCodecContext * avctx)280 static av_cold int mlp_decode_init(AVCodecContext *avctx)
281 {
282 MLPDecodeContext *m = avctx->priv_data;
283 int substr;
284
285 init_static();
286 m->avctx = avctx;
287 for (substr = 0; substr < MAX_SUBSTREAMS; substr++)
288 m->substream[substr].lossless_check_data = 0xffffffff;
289 ff_mlpdsp_init(&m->dsp);
290
291 return 0;
292 }
293
294 /** Read a major sync info header - contains high level information about
295 * the stream - sample rate, channel arrangement etc. Most of this
296 * information is not actually necessary for decoding, only for playback.
297 */
298
read_major_sync(MLPDecodeContext * m,GetBitContext * gb)299 static int read_major_sync(MLPDecodeContext *m, GetBitContext *gb)
300 {
301 MLPHeaderInfo mh;
302 int substr, ret;
303
304 if ((ret = ff_mlp_read_major_sync(m->avctx, &mh, gb)) != 0)
305 return ret;
306
307 if (mh.group1_bits == 0) {
308 av_log(m->avctx, AV_LOG_ERROR, "invalid/unknown bits per sample\n");
309 return AVERROR_INVALIDDATA;
310 }
311 if (mh.group2_bits > mh.group1_bits) {
312 av_log(m->avctx, AV_LOG_ERROR,
313 "Channel group 2 cannot have more bits per sample than group 1.\n");
314 return AVERROR_INVALIDDATA;
315 }
316
317 if (mh.group2_samplerate && mh.group2_samplerate != mh.group1_samplerate) {
318 av_log(m->avctx, AV_LOG_ERROR,
319 "Channel groups with differing sample rates are not currently supported.\n");
320 return AVERROR_INVALIDDATA;
321 }
322
323 if (mh.group1_samplerate == 0) {
324 av_log(m->avctx, AV_LOG_ERROR, "invalid/unknown sampling rate\n");
325 return AVERROR_INVALIDDATA;
326 }
327 if (mh.group1_samplerate > MAX_SAMPLERATE) {
328 av_log(m->avctx, AV_LOG_ERROR,
329 "Sampling rate %d is greater than the supported maximum (%d).\n",
330 mh.group1_samplerate, MAX_SAMPLERATE);
331 return AVERROR_INVALIDDATA;
332 }
333 if (mh.access_unit_size > MAX_BLOCKSIZE) {
334 av_log(m->avctx, AV_LOG_ERROR,
335 "Block size %d is greater than the supported maximum (%d).\n",
336 mh.access_unit_size, MAX_BLOCKSIZE);
337 return AVERROR_INVALIDDATA;
338 }
339 if (mh.access_unit_size_pow2 > MAX_BLOCKSIZE_POW2) {
340 av_log(m->avctx, AV_LOG_ERROR,
341 "Block size pow2 %d is greater than the supported maximum (%d).\n",
342 mh.access_unit_size_pow2, MAX_BLOCKSIZE_POW2);
343 return AVERROR_INVALIDDATA;
344 }
345
346 if (mh.num_substreams == 0)
347 return AVERROR_INVALIDDATA;
348 if (m->avctx->codec_id == AV_CODEC_ID_MLP && mh.num_substreams > 2) {
349 av_log(m->avctx, AV_LOG_ERROR, "MLP only supports up to 2 substreams.\n");
350 return AVERROR_INVALIDDATA;
351 }
352 if (mh.num_substreams > MAX_SUBSTREAMS) {
353 avpriv_request_sample(m->avctx,
354 "%d substreams (more than the "
355 "maximum supported by the decoder)",
356 mh.num_substreams);
357 return AVERROR_PATCHWELCOME;
358 }
359
360 m->major_sync_header_size = mh.header_size;
361
362 m->access_unit_size = mh.access_unit_size;
363 m->access_unit_size_pow2 = mh.access_unit_size_pow2;
364
365 m->num_substreams = mh.num_substreams;
366
367 /* limit to decoding 3 substreams, as the 4th is used by Dolby Atmos for non-audio data */
368 m->max_decoded_substream = FFMIN(m->num_substreams - 1, 2);
369
370 m->avctx->sample_rate = mh.group1_samplerate;
371 m->avctx->frame_size = mh.access_unit_size;
372
373 m->avctx->bits_per_raw_sample = mh.group1_bits;
374 if (mh.group1_bits > 16)
375 m->avctx->sample_fmt = AV_SAMPLE_FMT_S32;
376 else
377 m->avctx->sample_fmt = AV_SAMPLE_FMT_S16;
378 m->dsp.mlp_pack_output = m->dsp.mlp_select_pack_output(m->substream[m->max_decoded_substream].ch_assign,
379 m->substream[m->max_decoded_substream].output_shift,
380 m->substream[m->max_decoded_substream].max_matrix_channel,
381 m->avctx->sample_fmt == AV_SAMPLE_FMT_S32);
382
383 m->params_valid = 1;
384 for (substr = 0; substr < MAX_SUBSTREAMS; substr++)
385 m->substream[substr].restart_seen = 0;
386
387 /* Set the layout for each substream. When there's more than one, the first
388 * substream is Stereo. Subsequent substreams' layouts are indicated in the
389 * major sync. */
390 if (m->avctx->codec_id == AV_CODEC_ID_MLP) {
391 if (mh.stream_type != 0xbb) {
392 avpriv_request_sample(m->avctx,
393 "unexpected stream_type %X in MLP",
394 mh.stream_type);
395 return AVERROR_PATCHWELCOME;
396 }
397 if ((substr = (mh.num_substreams > 1)))
398 m->substream[0].mask = AV_CH_LAYOUT_STEREO;
399 m->substream[substr].mask = mh.channel_layout_mlp;
400 } else {
401 if (mh.stream_type != 0xba) {
402 avpriv_request_sample(m->avctx,
403 "unexpected stream_type %X in !MLP",
404 mh.stream_type);
405 return AVERROR_PATCHWELCOME;
406 }
407 if ((substr = (mh.num_substreams > 1)))
408 m->substream[0].mask = AV_CH_LAYOUT_STEREO;
409 if (mh.num_substreams > 2)
410 if (mh.channel_layout_thd_stream2)
411 m->substream[2].mask = mh.channel_layout_thd_stream2;
412 else
413 m->substream[2].mask = mh.channel_layout_thd_stream1;
414 m->substream[substr].mask = mh.channel_layout_thd_stream1;
415
416 if (m->avctx->channels<=2 && m->substream[substr].mask == AV_CH_LAYOUT_MONO && m->max_decoded_substream == 1) {
417 av_log(m->avctx, AV_LOG_DEBUG, "Mono stream with 2 substreams, ignoring 2nd\n");
418 m->max_decoded_substream = 0;
419 if (m->avctx->channels==2)
420 m->avctx->channel_layout = AV_CH_LAYOUT_STEREO;
421 }
422 }
423
424 m->needs_reordering = mh.channel_arrangement >= 18 && mh.channel_arrangement <= 20;
425
426 /* Parse the TrueHD decoder channel modifiers and set each substream's
427 * AVMatrixEncoding accordingly.
428 *
429 * The meaning of the modifiers depends on the channel layout:
430 *
431 * - THD_CH_MODIFIER_LTRT, THD_CH_MODIFIER_LBINRBIN only apply to 2-channel
432 *
433 * - THD_CH_MODIFIER_MONO applies to 1-channel or 2-channel (dual mono)
434 *
435 * - THD_CH_MODIFIER_SURROUNDEX, THD_CH_MODIFIER_NOTSURROUNDEX only apply to
436 * layouts with an Ls/Rs channel pair
437 */
438 for (substr = 0; substr < MAX_SUBSTREAMS; substr++)
439 m->substream[substr].matrix_encoding = AV_MATRIX_ENCODING_NONE;
440 if (m->avctx->codec_id == AV_CODEC_ID_TRUEHD) {
441 if (mh.num_substreams > 2 &&
442 mh.channel_layout_thd_stream2 & AV_CH_SIDE_LEFT &&
443 mh.channel_layout_thd_stream2 & AV_CH_SIDE_RIGHT &&
444 mh.channel_modifier_thd_stream2 == THD_CH_MODIFIER_SURROUNDEX)
445 m->substream[2].matrix_encoding = AV_MATRIX_ENCODING_DOLBYEX;
446
447 if (mh.num_substreams > 1 &&
448 mh.channel_layout_thd_stream1 & AV_CH_SIDE_LEFT &&
449 mh.channel_layout_thd_stream1 & AV_CH_SIDE_RIGHT &&
450 mh.channel_modifier_thd_stream1 == THD_CH_MODIFIER_SURROUNDEX)
451 m->substream[1].matrix_encoding = AV_MATRIX_ENCODING_DOLBYEX;
452
453 if (mh.num_substreams > 0)
454 switch (mh.channel_modifier_thd_stream0) {
455 case THD_CH_MODIFIER_LTRT:
456 m->substream[0].matrix_encoding = AV_MATRIX_ENCODING_DOLBY;
457 break;
458 case THD_CH_MODIFIER_LBINRBIN:
459 m->substream[0].matrix_encoding = AV_MATRIX_ENCODING_DOLBYHEADPHONE;
460 break;
461 default:
462 break;
463 }
464 }
465
466 return 0;
467 }
468
469 /** Read a restart header from a block in a substream. This contains parameters
470 * required to decode the audio that do not change very often. Generally
471 * (always) present only in blocks following a major sync. */
472
read_restart_header(MLPDecodeContext * m,GetBitContext * gbp,const uint8_t * buf,unsigned int substr)473 static int read_restart_header(MLPDecodeContext *m, GetBitContext *gbp,
474 const uint8_t *buf, unsigned int substr)
475 {
476 SubStream *s = &m->substream[substr];
477 unsigned int ch;
478 int sync_word, tmp;
479 uint8_t checksum;
480 uint8_t lossless_check;
481 int start_count = get_bits_count(gbp);
482 int min_channel, max_channel, max_matrix_channel, noise_type;
483 const int std_max_matrix_channel = m->avctx->codec_id == AV_CODEC_ID_MLP
484 ? MAX_MATRIX_CHANNEL_MLP
485 : MAX_MATRIX_CHANNEL_TRUEHD;
486
487 sync_word = get_bits(gbp, 13);
488
489 if (sync_word != 0x31ea >> 1) {
490 av_log(m->avctx, AV_LOG_ERROR,
491 "restart header sync incorrect (got 0x%04x)\n", sync_word);
492 return AVERROR_INVALIDDATA;
493 }
494
495 noise_type = get_bits1(gbp);
496
497 if (m->avctx->codec_id == AV_CODEC_ID_MLP && noise_type) {
498 av_log(m->avctx, AV_LOG_ERROR, "MLP must have 0x31ea sync word.\n");
499 return AVERROR_INVALIDDATA;
500 }
501
502 skip_bits(gbp, 16); /* Output timestamp */
503
504 min_channel = get_bits(gbp, 4);
505 max_channel = get_bits(gbp, 4);
506 max_matrix_channel = get_bits(gbp, 4);
507
508 if (max_matrix_channel > std_max_matrix_channel) {
509 av_log(m->avctx, AV_LOG_ERROR,
510 "Max matrix channel cannot be greater than %d.\n",
511 std_max_matrix_channel);
512 return AVERROR_INVALIDDATA;
513 }
514
515 if (max_channel != max_matrix_channel) {
516 av_log(m->avctx, AV_LOG_ERROR,
517 "Max channel must be equal max matrix channel.\n");
518 return AVERROR_INVALIDDATA;
519 }
520
521 /* This should happen for TrueHD streams with >6 channels and MLP's noise
522 * type. It is not yet known if this is allowed. */
523 if (max_channel > MAX_MATRIX_CHANNEL_MLP && !noise_type) {
524 avpriv_request_sample(m->avctx,
525 "%d channels (more than the "
526 "maximum supported by the decoder)",
527 max_channel + 2);
528 return AVERROR_PATCHWELCOME;
529 }
530
531 if (min_channel > max_channel) {
532 av_log(m->avctx, AV_LOG_ERROR,
533 "Substream min channel cannot be greater than max channel.\n");
534 return AVERROR_INVALIDDATA;
535 }
536
537 s->min_channel = min_channel;
538 s->max_channel = max_channel;
539 s->max_matrix_channel = max_matrix_channel;
540 s->noise_type = noise_type;
541
542 if (mlp_channel_layout_subset(m->avctx->request_channel_layout, s->mask) &&
543 m->max_decoded_substream > substr) {
544 av_log(m->avctx, AV_LOG_DEBUG,
545 "Extracting %d-channel downmix (0x%"PRIx64") from substream %d. "
546 "Further substreams will be skipped.\n",
547 s->max_channel + 1, s->mask, substr);
548 m->max_decoded_substream = substr;
549 }
550
551 s->noise_shift = get_bits(gbp, 4);
552 s->noisegen_seed = get_bits(gbp, 23);
553
554 skip_bits(gbp, 19);
555
556 s->data_check_present = get_bits1(gbp);
557 lossless_check = get_bits(gbp, 8);
558 if (substr == m->max_decoded_substream
559 && s->lossless_check_data != 0xffffffff) {
560 tmp = xor_32_to_8(s->lossless_check_data);
561 if (tmp != lossless_check)
562 av_log(m->avctx, AV_LOG_WARNING,
563 "Lossless check failed - expected %02x, calculated %02x.\n",
564 lossless_check, tmp);
565 }
566
567 skip_bits(gbp, 16);
568
569 memset(s->ch_assign, 0, sizeof(s->ch_assign));
570
571 for (ch = 0; ch <= s->max_matrix_channel; ch++) {
572 int ch_assign = get_bits(gbp, 6);
573 if (m->avctx->codec_id == AV_CODEC_ID_TRUEHD) {
574 uint64_t channel = thd_channel_layout_extract_channel(s->mask,
575 ch_assign);
576 ch_assign = av_get_channel_layout_channel_index(s->mask,
577 channel);
578 }
579 if (ch_assign < 0 || ch_assign > s->max_matrix_channel) {
580 avpriv_request_sample(m->avctx,
581 "Assignment of matrix channel %d to invalid output channel %d",
582 ch, ch_assign);
583 return AVERROR_PATCHWELCOME;
584 }
585 s->ch_assign[ch_assign] = ch;
586 }
587
588 checksum = ff_mlp_restart_checksum(buf, get_bits_count(gbp) - start_count);
589
590 if (checksum != get_bits(gbp, 8))
591 av_log(m->avctx, AV_LOG_ERROR, "restart header checksum error\n");
592
593 /* Set default decoding parameters. */
594 s->param_presence_flags = 0xff;
595 s->num_primitive_matrices = 0;
596 s->blocksize = 8;
597 s->lossless_check_data = 0;
598
599 memset(s->output_shift , 0, sizeof(s->output_shift ));
600 memset(s->quant_step_size, 0, sizeof(s->quant_step_size));
601
602 for (ch = s->min_channel; ch <= s->max_channel; ch++) {
603 ChannelParams *cp = &s->channel_params[ch];
604 cp->filter_params[FIR].order = 0;
605 cp->filter_params[IIR].order = 0;
606 cp->filter_params[FIR].shift = 0;
607 cp->filter_params[IIR].shift = 0;
608
609 /* Default audio coding is 24-bit raw PCM. */
610 cp->huff_offset = 0;
611 cp->sign_huff_offset = -(1 << 23);
612 cp->codebook = 0;
613 cp->huff_lsbs = 24;
614 }
615
616 if (substr == m->max_decoded_substream) {
617 m->avctx->channels = s->max_matrix_channel + 1;
618 m->avctx->channel_layout = s->mask;
619 m->dsp.mlp_pack_output = m->dsp.mlp_select_pack_output(s->ch_assign,
620 s->output_shift,
621 s->max_matrix_channel,
622 m->avctx->sample_fmt == AV_SAMPLE_FMT_S32);
623
624 if (m->avctx->codec_id == AV_CODEC_ID_MLP && m->needs_reordering) {
625 if (m->avctx->channel_layout == (AV_CH_LAYOUT_QUAD|AV_CH_LOW_FREQUENCY) ||
626 m->avctx->channel_layout == AV_CH_LAYOUT_5POINT0_BACK) {
627 int i = s->ch_assign[4];
628 s->ch_assign[4] = s->ch_assign[3];
629 s->ch_assign[3] = s->ch_assign[2];
630 s->ch_assign[2] = i;
631 } else if (m->avctx->channel_layout == AV_CH_LAYOUT_5POINT1_BACK) {
632 FFSWAP(int, s->ch_assign[2], s->ch_assign[4]);
633 FFSWAP(int, s->ch_assign[3], s->ch_assign[5]);
634 }
635 }
636
637 }
638
639 return 0;
640 }
641
642 /** Read parameters for one of the prediction filters. */
643
read_filter_params(MLPDecodeContext * m,GetBitContext * gbp,unsigned int substr,unsigned int channel,unsigned int filter)644 static int read_filter_params(MLPDecodeContext *m, GetBitContext *gbp,
645 unsigned int substr, unsigned int channel,
646 unsigned int filter)
647 {
648 SubStream *s = &m->substream[substr];
649 FilterParams *fp = &s->channel_params[channel].filter_params[filter];
650 const int max_order = filter ? MAX_IIR_ORDER : MAX_FIR_ORDER;
651 const char fchar = filter ? 'I' : 'F';
652 int i, order;
653
654 // Filter is 0 for FIR, 1 for IIR.
655 av_assert0(filter < 2);
656
657 if (m->filter_changed[channel][filter]++ > 1) {
658 av_log(m->avctx, AV_LOG_ERROR, "Filters may change only once per access unit.\n");
659 return AVERROR_INVALIDDATA;
660 }
661
662 order = get_bits(gbp, 4);
663 if (order > max_order) {
664 av_log(m->avctx, AV_LOG_ERROR,
665 "%cIR filter order %d is greater than maximum %d.\n",
666 fchar, order, max_order);
667 return AVERROR_INVALIDDATA;
668 }
669 fp->order = order;
670
671 if (order > 0) {
672 int32_t *fcoeff = s->channel_params[channel].coeff[filter];
673 int coeff_bits, coeff_shift;
674
675 fp->shift = get_bits(gbp, 4);
676
677 coeff_bits = get_bits(gbp, 5);
678 coeff_shift = get_bits(gbp, 3);
679 if (coeff_bits < 1 || coeff_bits > 16) {
680 av_log(m->avctx, AV_LOG_ERROR,
681 "%cIR filter coeff_bits must be between 1 and 16.\n",
682 fchar);
683 return AVERROR_INVALIDDATA;
684 }
685 if (coeff_bits + coeff_shift > 16) {
686 av_log(m->avctx, AV_LOG_ERROR,
687 "Sum of coeff_bits and coeff_shift for %cIR filter must be 16 or less.\n",
688 fchar);
689 return AVERROR_INVALIDDATA;
690 }
691
692 for (i = 0; i < order; i++)
693 fcoeff[i] = get_sbits(gbp, coeff_bits) * (1 << coeff_shift);
694
695 if (get_bits1(gbp)) {
696 int state_bits, state_shift;
697
698 if (filter == FIR) {
699 av_log(m->avctx, AV_LOG_ERROR,
700 "FIR filter has state data specified.\n");
701 return AVERROR_INVALIDDATA;
702 }
703
704 state_bits = get_bits(gbp, 4);
705 state_shift = get_bits(gbp, 4);
706
707 /* TODO: Check validity of state data. */
708
709 for (i = 0; i < order; i++)
710 fp->state[i] = state_bits ? get_sbits(gbp, state_bits) * (1 << state_shift) : 0;
711 }
712 }
713
714 return 0;
715 }
716
717 /** Read parameters for primitive matrices. */
718
read_matrix_params(MLPDecodeContext * m,unsigned int substr,GetBitContext * gbp)719 static int read_matrix_params(MLPDecodeContext *m, unsigned int substr, GetBitContext *gbp)
720 {
721 SubStream *s = &m->substream[substr];
722 unsigned int mat, ch;
723 const int max_primitive_matrices = m->avctx->codec_id == AV_CODEC_ID_MLP
724 ? MAX_MATRICES_MLP
725 : MAX_MATRICES_TRUEHD;
726
727 if (m->matrix_changed++ > 1) {
728 av_log(m->avctx, AV_LOG_ERROR, "Matrices may change only once per access unit.\n");
729 return AVERROR_INVALIDDATA;
730 }
731
732 s->num_primitive_matrices = get_bits(gbp, 4);
733
734 if (s->num_primitive_matrices > max_primitive_matrices) {
735 av_log(m->avctx, AV_LOG_ERROR,
736 "Number of primitive matrices cannot be greater than %d.\n",
737 max_primitive_matrices);
738 goto error;
739 }
740
741 for (mat = 0; mat < s->num_primitive_matrices; mat++) {
742 int frac_bits, max_chan;
743 s->matrix_out_ch[mat] = get_bits(gbp, 4);
744 frac_bits = get_bits(gbp, 4);
745 s->lsb_bypass [mat] = get_bits1(gbp);
746
747 if (s->matrix_out_ch[mat] > s->max_matrix_channel) {
748 av_log(m->avctx, AV_LOG_ERROR,
749 "Invalid channel %d specified as output from matrix.\n",
750 s->matrix_out_ch[mat]);
751 goto error;
752 }
753 if (frac_bits > 14) {
754 av_log(m->avctx, AV_LOG_ERROR,
755 "Too many fractional bits specified.\n");
756 goto error;
757 }
758
759 max_chan = s->max_matrix_channel;
760 if (!s->noise_type)
761 max_chan+=2;
762
763 for (ch = 0; ch <= max_chan; ch++) {
764 int coeff_val = 0;
765 if (get_bits1(gbp))
766 coeff_val = get_sbits(gbp, frac_bits + 2);
767
768 s->matrix_coeff[mat][ch] = coeff_val * (1 << (14 - frac_bits));
769 }
770
771 if (s->noise_type)
772 s->matrix_noise_shift[mat] = get_bits(gbp, 4);
773 else
774 s->matrix_noise_shift[mat] = 0;
775 }
776
777 return 0;
778 error:
779 s->num_primitive_matrices = 0;
780 memset(s->matrix_out_ch, 0, sizeof(s->matrix_out_ch));
781
782 return AVERROR_INVALIDDATA;
783 }
784
785 /** Read channel parameters. */
786
read_channel_params(MLPDecodeContext * m,unsigned int substr,GetBitContext * gbp,unsigned int ch)787 static int read_channel_params(MLPDecodeContext *m, unsigned int substr,
788 GetBitContext *gbp, unsigned int ch)
789 {
790 SubStream *s = &m->substream[substr];
791 ChannelParams *cp = &s->channel_params[ch];
792 FilterParams *fir = &cp->filter_params[FIR];
793 FilterParams *iir = &cp->filter_params[IIR];
794 int ret;
795
796 if (s->param_presence_flags & PARAM_FIR)
797 if (get_bits1(gbp))
798 if ((ret = read_filter_params(m, gbp, substr, ch, FIR)) < 0)
799 return ret;
800
801 if (s->param_presence_flags & PARAM_IIR)
802 if (get_bits1(gbp))
803 if ((ret = read_filter_params(m, gbp, substr, ch, IIR)) < 0)
804 return ret;
805
806 if (fir->order + iir->order > 8) {
807 av_log(m->avctx, AV_LOG_ERROR, "Total filter orders too high.\n");
808 return AVERROR_INVALIDDATA;
809 }
810
811 if (fir->order && iir->order &&
812 fir->shift != iir->shift) {
813 av_log(m->avctx, AV_LOG_ERROR,
814 "FIR and IIR filters must use the same precision.\n");
815 return AVERROR_INVALIDDATA;
816 }
817 /* The FIR and IIR filters must have the same precision.
818 * To simplify the filtering code, only the precision of the
819 * FIR filter is considered. If only the IIR filter is employed,
820 * the FIR filter precision is set to that of the IIR filter, so
821 * that the filtering code can use it. */
822 if (!fir->order && iir->order)
823 fir->shift = iir->shift;
824
825 if (s->param_presence_flags & PARAM_HUFFOFFSET)
826 if (get_bits1(gbp))
827 cp->huff_offset = get_sbits(gbp, 15);
828
829 cp->codebook = get_bits(gbp, 2);
830 cp->huff_lsbs = get_bits(gbp, 5);
831
832 if (cp->codebook > 0 && cp->huff_lsbs > 24) {
833 av_log(m->avctx, AV_LOG_ERROR, "Invalid huff_lsbs.\n");
834 cp->huff_lsbs = 0;
835 return AVERROR_INVALIDDATA;
836 }
837
838 return 0;
839 }
840
841 /** Read decoding parameters that change more often than those in the restart
842 * header. */
843
read_decoding_params(MLPDecodeContext * m,GetBitContext * gbp,unsigned int substr)844 static int read_decoding_params(MLPDecodeContext *m, GetBitContext *gbp,
845 unsigned int substr)
846 {
847 SubStream *s = &m->substream[substr];
848 unsigned int ch;
849 int ret = 0;
850 unsigned recompute_sho = 0;
851
852 if (s->param_presence_flags & PARAM_PRESENCE)
853 if (get_bits1(gbp))
854 s->param_presence_flags = get_bits(gbp, 8);
855
856 if (s->param_presence_flags & PARAM_BLOCKSIZE)
857 if (get_bits1(gbp)) {
858 s->blocksize = get_bits(gbp, 9);
859 if (s->blocksize < 8 || s->blocksize > m->access_unit_size) {
860 av_log(m->avctx, AV_LOG_ERROR, "Invalid blocksize.\n");
861 s->blocksize = 0;
862 return AVERROR_INVALIDDATA;
863 }
864 }
865
866 if (s->param_presence_flags & PARAM_MATRIX)
867 if (get_bits1(gbp))
868 if ((ret = read_matrix_params(m, substr, gbp)) < 0)
869 return ret;
870
871 if (s->param_presence_flags & PARAM_OUTSHIFT)
872 if (get_bits1(gbp)) {
873 for (ch = 0; ch <= s->max_matrix_channel; ch++) {
874 s->output_shift[ch] = get_sbits(gbp, 4);
875 if (s->output_shift[ch] < 0) {
876 avpriv_request_sample(m->avctx, "Negative output_shift");
877 s->output_shift[ch] = 0;
878 }
879 }
880 if (substr == m->max_decoded_substream)
881 m->dsp.mlp_pack_output = m->dsp.mlp_select_pack_output(s->ch_assign,
882 s->output_shift,
883 s->max_matrix_channel,
884 m->avctx->sample_fmt == AV_SAMPLE_FMT_S32);
885 }
886
887 if (s->param_presence_flags & PARAM_QUANTSTEP)
888 if (get_bits1(gbp))
889 for (ch = 0; ch <= s->max_channel; ch++) {
890 s->quant_step_size[ch] = get_bits(gbp, 4);
891
892 recompute_sho |= 1<<ch;
893 }
894
895 for (ch = s->min_channel; ch <= s->max_channel; ch++)
896 if (get_bits1(gbp)) {
897 recompute_sho |= 1<<ch;
898 if ((ret = read_channel_params(m, substr, gbp, ch)) < 0)
899 goto fail;
900 }
901
902
903 fail:
904 for (ch = 0; ch <= s->max_channel; ch++) {
905 if (recompute_sho & (1<<ch)) {
906 ChannelParams *cp = &s->channel_params[ch];
907
908 if (cp->codebook > 0 && cp->huff_lsbs < s->quant_step_size[ch]) {
909 if (ret >= 0) {
910 av_log(m->avctx, AV_LOG_ERROR, "quant_step_size larger than huff_lsbs\n");
911 ret = AVERROR_INVALIDDATA;
912 }
913 s->quant_step_size[ch] = 0;
914 }
915
916 cp->sign_huff_offset = calculate_sign_huff(m, substr, ch);
917 }
918 }
919 return ret;
920 }
921
922 #define MSB_MASK(bits) (-1u << (bits))
923
924 /** Generate PCM samples using the prediction filters and residual values
925 * read from the data stream, and update the filter state. */
926
filter_channel(MLPDecodeContext * m,unsigned int substr,unsigned int channel)927 static void filter_channel(MLPDecodeContext *m, unsigned int substr,
928 unsigned int channel)
929 {
930 SubStream *s = &m->substream[substr];
931 const int32_t *fircoeff = s->channel_params[channel].coeff[FIR];
932 int32_t state_buffer[NUM_FILTERS][MAX_BLOCKSIZE + MAX_FIR_ORDER];
933 int32_t *firbuf = state_buffer[FIR] + MAX_BLOCKSIZE;
934 int32_t *iirbuf = state_buffer[IIR] + MAX_BLOCKSIZE;
935 FilterParams *fir = &s->channel_params[channel].filter_params[FIR];
936 FilterParams *iir = &s->channel_params[channel].filter_params[IIR];
937 unsigned int filter_shift = fir->shift;
938 int32_t mask = MSB_MASK(s->quant_step_size[channel]);
939
940 memcpy(firbuf, fir->state, MAX_FIR_ORDER * sizeof(int32_t));
941 memcpy(iirbuf, iir->state, MAX_IIR_ORDER * sizeof(int32_t));
942
943 m->dsp.mlp_filter_channel(firbuf, fircoeff,
944 fir->order, iir->order,
945 filter_shift, mask, s->blocksize,
946 &m->sample_buffer[s->blockpos][channel]);
947
948 memcpy(fir->state, firbuf - s->blocksize, MAX_FIR_ORDER * sizeof(int32_t));
949 memcpy(iir->state, iirbuf - s->blocksize, MAX_IIR_ORDER * sizeof(int32_t));
950 }
951
952 /** Read a block of PCM residual data (or actual if no filtering active). */
953
read_block_data(MLPDecodeContext * m,GetBitContext * gbp,unsigned int substr)954 static int read_block_data(MLPDecodeContext *m, GetBitContext *gbp,
955 unsigned int substr)
956 {
957 SubStream *s = &m->substream[substr];
958 unsigned int i, ch, expected_stream_pos = 0;
959 int ret;
960
961 if (s->data_check_present) {
962 expected_stream_pos = get_bits_count(gbp);
963 expected_stream_pos += get_bits(gbp, 16);
964 avpriv_request_sample(m->avctx,
965 "Substreams with VLC block size check info");
966 }
967
968 if (s->blockpos + s->blocksize > m->access_unit_size) {
969 av_log(m->avctx, AV_LOG_ERROR, "too many audio samples in frame\n");
970 return AVERROR_INVALIDDATA;
971 }
972
973 memset(&m->bypassed_lsbs[s->blockpos][0], 0,
974 s->blocksize * sizeof(m->bypassed_lsbs[0]));
975
976 for (i = 0; i < s->blocksize; i++)
977 if ((ret = read_huff_channels(m, gbp, substr, i)) < 0)
978 return ret;
979
980 for (ch = s->min_channel; ch <= s->max_channel; ch++)
981 filter_channel(m, substr, ch);
982
983 s->blockpos += s->blocksize;
984
985 if (s->data_check_present) {
986 if (get_bits_count(gbp) != expected_stream_pos)
987 av_log(m->avctx, AV_LOG_ERROR, "block data length mismatch\n");
988 skip_bits(gbp, 8);
989 }
990
991 return 0;
992 }
993
994 /** Data table used for TrueHD noise generation function. */
995
996 static const int8_t noise_table[256] = {
997 30, 51, 22, 54, 3, 7, -4, 38, 14, 55, 46, 81, 22, 58, -3, 2,
998 52, 31, -7, 51, 15, 44, 74, 30, 85, -17, 10, 33, 18, 80, 28, 62,
999 10, 32, 23, 69, 72, 26, 35, 17, 73, 60, 8, 56, 2, 6, -2, -5,
1000 51, 4, 11, 50, 66, 76, 21, 44, 33, 47, 1, 26, 64, 48, 57, 40,
1001 38, 16, -10, -28, 92, 22, -18, 29, -10, 5, -13, 49, 19, 24, 70, 34,
1002 61, 48, 30, 14, -6, 25, 58, 33, 42, 60, 67, 17, 54, 17, 22, 30,
1003 67, 44, -9, 50, -11, 43, 40, 32, 59, 82, 13, 49, -14, 55, 60, 36,
1004 48, 49, 31, 47, 15, 12, 4, 65, 1, 23, 29, 39, 45, -2, 84, 69,
1005 0, 72, 37, 57, 27, 41, -15, -16, 35, 31, 14, 61, 24, 0, 27, 24,
1006 16, 41, 55, 34, 53, 9, 56, 12, 25, 29, 53, 5, 20, -20, -8, 20,
1007 13, 28, -3, 78, 38, 16, 11, 62, 46, 29, 21, 24, 46, 65, 43, -23,
1008 89, 18, 74, 21, 38, -12, 19, 12, -19, 8, 15, 33, 4, 57, 9, -8,
1009 36, 35, 26, 28, 7, 83, 63, 79, 75, 11, 3, 87, 37, 47, 34, 40,
1010 39, 19, 20, 42, 27, 34, 39, 77, 13, 42, 59, 64, 45, -1, 32, 37,
1011 45, -5, 53, -6, 7, 36, 50, 23, 6, 32, 9, -21, 18, 71, 27, 52,
1012 -25, 31, 35, 42, -1, 68, 63, 52, 26, 43, 66, 37, 41, 25, 40, 70,
1013 };
1014
1015 /** Noise generation functions.
1016 * I'm not sure what these are for - they seem to be some kind of pseudorandom
1017 * sequence generators, used to generate noise data which is used when the
1018 * channels are rematrixed. I'm not sure if they provide a practical benefit
1019 * to compression, or just obfuscate the decoder. Are they for some kind of
1020 * dithering? */
1021
1022 /** Generate two channels of noise, used in the matrix when
1023 * restart sync word == 0x31ea. */
1024
generate_2_noise_channels(MLPDecodeContext * m,unsigned int substr)1025 static void generate_2_noise_channels(MLPDecodeContext *m, unsigned int substr)
1026 {
1027 SubStream *s = &m->substream[substr];
1028 unsigned int i;
1029 uint32_t seed = s->noisegen_seed;
1030 unsigned int maxchan = s->max_matrix_channel;
1031
1032 for (i = 0; i < s->blockpos; i++) {
1033 uint16_t seed_shr7 = seed >> 7;
1034 m->sample_buffer[i][maxchan+1] = ((int8_t)(seed >> 15)) * (1 << s->noise_shift);
1035 m->sample_buffer[i][maxchan+2] = ((int8_t) seed_shr7) * (1 << s->noise_shift);
1036
1037 seed = (seed << 16) ^ seed_shr7 ^ (seed_shr7 << 5);
1038 }
1039
1040 s->noisegen_seed = seed;
1041 }
1042
1043 /** Generate a block of noise, used when restart sync word == 0x31eb. */
1044
fill_noise_buffer(MLPDecodeContext * m,unsigned int substr)1045 static void fill_noise_buffer(MLPDecodeContext *m, unsigned int substr)
1046 {
1047 SubStream *s = &m->substream[substr];
1048 unsigned int i;
1049 uint32_t seed = s->noisegen_seed;
1050
1051 for (i = 0; i < m->access_unit_size_pow2; i++) {
1052 uint8_t seed_shr15 = seed >> 15;
1053 m->noise_buffer[i] = noise_table[seed_shr15];
1054 seed = (seed << 8) ^ seed_shr15 ^ (seed_shr15 << 5);
1055 }
1056
1057 s->noisegen_seed = seed;
1058 }
1059
1060 /** Write the audio data into the output buffer. */
1061
output_data(MLPDecodeContext * m,unsigned int substr,AVFrame * frame,int * got_frame_ptr)1062 static int output_data(MLPDecodeContext *m, unsigned int substr,
1063 AVFrame *frame, int *got_frame_ptr)
1064 {
1065 AVCodecContext *avctx = m->avctx;
1066 SubStream *s = &m->substream[substr];
1067 unsigned int mat;
1068 unsigned int maxchan;
1069 int ret;
1070 int is32 = (m->avctx->sample_fmt == AV_SAMPLE_FMT_S32);
1071
1072 if (m->avctx->channels != s->max_matrix_channel + 1) {
1073 av_log(m->avctx, AV_LOG_ERROR, "channel count mismatch\n");
1074 return AVERROR_INVALIDDATA;
1075 }
1076
1077 if (!s->blockpos) {
1078 av_log(avctx, AV_LOG_ERROR, "No samples to output.\n");
1079 return AVERROR_INVALIDDATA;
1080 }
1081
1082 maxchan = s->max_matrix_channel;
1083 if (!s->noise_type) {
1084 generate_2_noise_channels(m, substr);
1085 maxchan += 2;
1086 } else {
1087 fill_noise_buffer(m, substr);
1088 }
1089
1090 /* Apply the channel matrices in turn to reconstruct the original audio
1091 * samples. */
1092 for (mat = 0; mat < s->num_primitive_matrices; mat++) {
1093 unsigned int dest_ch = s->matrix_out_ch[mat];
1094 m->dsp.mlp_rematrix_channel(&m->sample_buffer[0][0],
1095 s->matrix_coeff[mat],
1096 &m->bypassed_lsbs[0][mat],
1097 m->noise_buffer,
1098 s->num_primitive_matrices - mat,
1099 dest_ch,
1100 s->blockpos,
1101 maxchan,
1102 s->matrix_noise_shift[mat],
1103 m->access_unit_size_pow2,
1104 MSB_MASK(s->quant_step_size[dest_ch]));
1105 }
1106
1107 /* get output buffer */
1108 frame->nb_samples = s->blockpos;
1109 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1110 return ret;
1111 s->lossless_check_data = m->dsp.mlp_pack_output(s->lossless_check_data,
1112 s->blockpos,
1113 m->sample_buffer,
1114 frame->data[0],
1115 s->ch_assign,
1116 s->output_shift,
1117 s->max_matrix_channel,
1118 is32);
1119
1120 /* Update matrix encoding side data */
1121 if ((ret = ff_side_data_update_matrix_encoding(frame, s->matrix_encoding)) < 0)
1122 return ret;
1123
1124 *got_frame_ptr = 1;
1125
1126 return 0;
1127 }
1128
1129 /** Read an access unit from the stream.
1130 * @return negative on error, 0 if not enough data is present in the input stream,
1131 * otherwise the number of bytes consumed. */
1132
read_access_unit(AVCodecContext * avctx,void * data,int * got_frame_ptr,AVPacket * avpkt)1133 static int read_access_unit(AVCodecContext *avctx, void* data,
1134 int *got_frame_ptr, AVPacket *avpkt)
1135 {
1136 const uint8_t *buf = avpkt->data;
1137 int buf_size = avpkt->size;
1138 MLPDecodeContext *m = avctx->priv_data;
1139 GetBitContext gb;
1140 unsigned int length, substr;
1141 unsigned int substream_start;
1142 unsigned int header_size = 4;
1143 unsigned int substr_header_size = 0;
1144 uint8_t substream_parity_present[MAX_SUBSTREAMS];
1145 uint16_t substream_data_len[MAX_SUBSTREAMS];
1146 uint8_t parity_bits;
1147 int ret;
1148
1149 if (buf_size < 4)
1150 return AVERROR_INVALIDDATA;
1151
1152 length = (AV_RB16(buf) & 0xfff) * 2;
1153
1154 if (length < 4 || length > buf_size)
1155 return AVERROR_INVALIDDATA;
1156
1157 init_get_bits(&gb, (buf + 4), (length - 4) * 8);
1158
1159 m->is_major_sync_unit = 0;
1160 if (show_bits_long(&gb, 31) == (0xf8726fba >> 1)) {
1161 if (read_major_sync(m, &gb) < 0)
1162 goto error;
1163 m->is_major_sync_unit = 1;
1164 header_size += m->major_sync_header_size;
1165 }
1166
1167 if (!m->params_valid) {
1168 av_log(m->avctx, AV_LOG_WARNING,
1169 "Stream parameters not seen; skipping frame.\n");
1170 *got_frame_ptr = 0;
1171 return length;
1172 }
1173
1174 substream_start = 0;
1175
1176 for (substr = 0; substr < m->num_substreams; substr++) {
1177 int extraword_present, checkdata_present, end, nonrestart_substr;
1178
1179 extraword_present = get_bits1(&gb);
1180 nonrestart_substr = get_bits1(&gb);
1181 checkdata_present = get_bits1(&gb);
1182 skip_bits1(&gb);
1183
1184 end = get_bits(&gb, 12) * 2;
1185
1186 substr_header_size += 2;
1187
1188 if (extraword_present) {
1189 if (m->avctx->codec_id == AV_CODEC_ID_MLP) {
1190 av_log(m->avctx, AV_LOG_ERROR, "There must be no extraword for MLP.\n");
1191 goto error;
1192 }
1193 skip_bits(&gb, 16);
1194 substr_header_size += 2;
1195 }
1196
1197 if (length < header_size + substr_header_size) {
1198 av_log(m->avctx, AV_LOG_ERROR, "Insufficient data for headers\n");
1199 goto error;
1200 }
1201
1202 if (!(nonrestart_substr ^ m->is_major_sync_unit)) {
1203 av_log(m->avctx, AV_LOG_ERROR, "Invalid nonrestart_substr.\n");
1204 goto error;
1205 }
1206
1207 if (end + header_size + substr_header_size > length) {
1208 av_log(m->avctx, AV_LOG_ERROR,
1209 "Indicated length of substream %d data goes off end of "
1210 "packet.\n", substr);
1211 end = length - header_size - substr_header_size;
1212 }
1213
1214 if (end < substream_start) {
1215 av_log(avctx, AV_LOG_ERROR,
1216 "Indicated end offset of substream %d data "
1217 "is smaller than calculated start offset.\n",
1218 substr);
1219 goto error;
1220 }
1221
1222 if (substr > m->max_decoded_substream)
1223 continue;
1224
1225 substream_parity_present[substr] = checkdata_present;
1226 substream_data_len[substr] = end - substream_start;
1227 substream_start = end;
1228 }
1229
1230 parity_bits = ff_mlp_calculate_parity(buf, 4);
1231 parity_bits ^= ff_mlp_calculate_parity(buf + header_size, substr_header_size);
1232
1233 if ((((parity_bits >> 4) ^ parity_bits) & 0xF) != 0xF) {
1234 av_log(avctx, AV_LOG_ERROR, "Parity check failed.\n");
1235 goto error;
1236 }
1237
1238 buf += header_size + substr_header_size;
1239
1240 for (substr = 0; substr <= m->max_decoded_substream; substr++) {
1241 SubStream *s = &m->substream[substr];
1242 init_get_bits(&gb, buf, substream_data_len[substr] * 8);
1243
1244 m->matrix_changed = 0;
1245 memset(m->filter_changed, 0, sizeof(m->filter_changed));
1246
1247 s->blockpos = 0;
1248 do {
1249 if (get_bits1(&gb)) {
1250 if (get_bits1(&gb)) {
1251 /* A restart header should be present. */
1252 if (read_restart_header(m, &gb, buf, substr) < 0)
1253 goto next_substr;
1254 s->restart_seen = 1;
1255 }
1256
1257 if (!s->restart_seen)
1258 goto next_substr;
1259 if (read_decoding_params(m, &gb, substr) < 0)
1260 goto next_substr;
1261 }
1262
1263 if (!s->restart_seen)
1264 goto next_substr;
1265
1266 if ((ret = read_block_data(m, &gb, substr)) < 0)
1267 return ret;
1268
1269 if (get_bits_count(&gb) >= substream_data_len[substr] * 8)
1270 goto substream_length_mismatch;
1271
1272 } while (!get_bits1(&gb));
1273
1274 skip_bits(&gb, (-get_bits_count(&gb)) & 15);
1275
1276 if (substream_data_len[substr] * 8 - get_bits_count(&gb) >= 32) {
1277 int shorten_by;
1278
1279 if (get_bits(&gb, 16) != 0xD234)
1280 return AVERROR_INVALIDDATA;
1281
1282 shorten_by = get_bits(&gb, 16);
1283 if (m->avctx->codec_id == AV_CODEC_ID_TRUEHD && shorten_by & 0x2000)
1284 s->blockpos -= FFMIN(shorten_by & 0x1FFF, s->blockpos);
1285 else if (m->avctx->codec_id == AV_CODEC_ID_MLP && shorten_by != 0xD234)
1286 return AVERROR_INVALIDDATA;
1287
1288 if (substr == m->max_decoded_substream)
1289 av_log(m->avctx, AV_LOG_INFO, "End of stream indicated.\n");
1290 }
1291
1292 if (substream_parity_present[substr]) {
1293 uint8_t parity, checksum;
1294
1295 if (substream_data_len[substr] * 8 - get_bits_count(&gb) != 16)
1296 goto substream_length_mismatch;
1297
1298 parity = ff_mlp_calculate_parity(buf, substream_data_len[substr] - 2);
1299 checksum = ff_mlp_checksum8 (buf, substream_data_len[substr] - 2);
1300
1301 if ((get_bits(&gb, 8) ^ parity) != 0xa9 )
1302 av_log(m->avctx, AV_LOG_ERROR, "Substream %d parity check failed.\n", substr);
1303 if ( get_bits(&gb, 8) != checksum)
1304 av_log(m->avctx, AV_LOG_ERROR, "Substream %d checksum failed.\n" , substr);
1305 }
1306
1307 if (substream_data_len[substr] * 8 != get_bits_count(&gb))
1308 goto substream_length_mismatch;
1309
1310 next_substr:
1311 if (!s->restart_seen)
1312 av_log(m->avctx, AV_LOG_ERROR,
1313 "No restart header present in substream %d.\n", substr);
1314
1315 buf += substream_data_len[substr];
1316 }
1317
1318 if ((ret = output_data(m, m->max_decoded_substream, data, got_frame_ptr)) < 0)
1319 return ret;
1320
1321 return length;
1322
1323 substream_length_mismatch:
1324 av_log(m->avctx, AV_LOG_ERROR, "substream %d length mismatch\n", substr);
1325 return AVERROR_INVALIDDATA;
1326
1327 error:
1328 m->params_valid = 0;
1329 return AVERROR_INVALIDDATA;
1330 }
1331
1332 #if CONFIG_MLP_DECODER
1333 AVCodec ff_mlp_decoder = {
1334 .name = "mlp",
1335 .long_name = NULL_IF_CONFIG_SMALL("MLP (Meridian Lossless Packing)"),
1336 .type = AVMEDIA_TYPE_AUDIO,
1337 .id = AV_CODEC_ID_MLP,
1338 .priv_data_size = sizeof(MLPDecodeContext),
1339 .init = mlp_decode_init,
1340 .decode = read_access_unit,
1341 .capabilities = AV_CODEC_CAP_DR1,
1342 };
1343 #endif
1344 #if CONFIG_TRUEHD_DECODER
1345 AVCodec ff_truehd_decoder = {
1346 .name = "truehd",
1347 .long_name = NULL_IF_CONFIG_SMALL("TrueHD"),
1348 .type = AVMEDIA_TYPE_AUDIO,
1349 .id = AV_CODEC_ID_TRUEHD,
1350 .priv_data_size = sizeof(MLPDecodeContext),
1351 .init = mlp_decode_init,
1352 .decode = read_access_unit,
1353 .capabilities = AV_CODEC_CAP_DR1,
1354 };
1355 #endif /* CONFIG_TRUEHD_DECODER */
1356