3 * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ mail.de>
5 * This file is part of FFmpeg.
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.
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.
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
25 * @author Thilo Borgmann <thilo.borgmann _at_ mail.de>
31 #include "mpeg4audio.h"
32 #include "bytestream.h"
36 #include "libavutil/samplefmt.h"
37 #include "libavutil/crc.h"
41 /** Rice parameters and corresponding index offsets for decoding the
42 * indices of scaled PARCOR values. The table chosen is set globally
43 * by the encoder and stored in ALSSpecificConfig.
45 static const int8_t parcor_rice_table[3][20][2] = {
46 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
47 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
48 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
49 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
50 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
51 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
52 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
53 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
54 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
55 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
56 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
57 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
61 /** Scaled PARCOR values used for the first two PARCOR coefficients.
62 * To be indexed by the Rice coded indices.
63 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
64 * Actual values are divided by 32 in order to be stored in 16 bits.
66 static const int16_t parcor_scaled_values[] = {
67 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
68 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
69 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
70 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
71 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
72 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
73 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
74 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
75 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
76 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
77 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
78 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
79 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
80 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
81 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
82 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
83 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
84 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
85 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
86 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
87 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
88 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
89 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
90 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
91 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
92 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
93 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
94 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
95 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
96 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
97 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
98 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
102 /** Gain values of p(0) for long-term prediction.
103 * To be indexed by the Rice coded indices.
105 static const uint8_t ltp_gain_values [4][4] = {
113 /** Inter-channel weighting factors for multi-channel correlation.
114 * To be indexed by the Rice coded indices.
116 static const int16_t mcc_weightings[] = {
117 204, 192, 179, 166, 153, 140, 128, 115,
118 102, 89, 76, 64, 51, 38, 25, 12,
119 0, -12, -25, -38, -51, -64, -76, -89,
120 -102, -115, -128, -140, -153, -166, -179, -192
124 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
126 static const uint8_t tail_code[16][6] = {
127 { 74, 44, 25, 13, 7, 3},
128 { 68, 42, 24, 13, 7, 3},
129 { 58, 39, 23, 13, 7, 3},
130 {126, 70, 37, 19, 10, 5},
131 {132, 70, 37, 20, 10, 5},
132 {124, 70, 38, 20, 10, 5},
133 {120, 69, 37, 20, 11, 5},
134 {116, 67, 37, 20, 11, 5},
135 {108, 66, 36, 20, 10, 5},
136 {102, 62, 36, 20, 10, 5},
137 { 88, 58, 34, 19, 10, 5},
138 {162, 89, 49, 25, 13, 7},
139 {156, 87, 49, 26, 14, 7},
140 {150, 86, 47, 26, 14, 7},
141 {142, 84, 47, 26, 14, 7},
142 {131, 79, 46, 26, 14, 7}
154 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
155 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
156 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
157 int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
158 int frame_length; ///< frame length for each frame (last frame may differ)
159 int ra_distance; ///< distance between RA frames (in frames, 0...255)
160 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
161 int adapt_order; ///< adaptive order: 1 = on, 0 = off
162 int coef_table; ///< table index of Rice code parameters
163 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
164 int max_order; ///< maximum prediction order (0..1023)
165 int block_switching; ///< number of block switching levels
166 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
167 int sb_part; ///< sub-block partition
168 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
169 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
170 int chan_config; ///< indicates that a chan_config_info field is present
171 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
172 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
173 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
174 int *chan_pos; ///< original channel positions
175 int crc_enabled; ///< enable Cyclic Redundancy Checksum
190 AVCodecContext *avctx;
191 ALSSpecificConfig sconf;
194 const AVCRC *crc_table;
195 uint32_t crc_org; ///< CRC value of the original input data
196 uint32_t crc; ///< CRC value calculated from decoded data
197 unsigned int cur_frame_length; ///< length of the current frame to decode
198 unsigned int frame_id; ///< the frame ID / number of the current frame
199 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
200 unsigned int cs_switch; ///< if true, channel rearrangement is done
201 unsigned int num_blocks; ///< number of blocks used in the current frame
202 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
203 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
204 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
205 int ltp_lag_length; ///< number of bits used for ltp lag value
206 int *const_block; ///< contains const_block flags for all channels
207 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
208 unsigned int *opt_order; ///< contains opt_order flags for all channels
209 int *store_prev_samples; ///< contains store_prev_samples flags for all channels
210 int *use_ltp; ///< contains use_ltp flags for all channels
211 int *ltp_lag; ///< contains ltp lag values for all channels
212 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
213 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
214 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
215 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
216 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
217 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
218 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
219 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
220 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
221 int *reverted_channels; ///< stores a flag for each reverted channel
222 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
223 int32_t **raw_samples; ///< decoded raw samples for each channel
224 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
225 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
230 unsigned int block_length; ///< number of samples within the block
231 unsigned int ra_block; ///< if true, this is a random access block
232 int *const_block; ///< if true, this is a constant value block
233 int js_blocks; ///< true if this block contains a difference signal
234 unsigned int *shift_lsbs; ///< shift of values for this block
235 unsigned int *opt_order; ///< prediction order of this block
236 int *store_prev_samples;///< if true, carryover samples have to be stored
237 int *use_ltp; ///< if true, long-term prediction is used
238 int *ltp_lag; ///< lag value for long-term prediction
239 int *ltp_gain; ///< gain values for ltp 5-tap filter
240 int32_t *quant_cof; ///< quantized parcor coefficients
241 int32_t *lpc_cof; ///< coefficients of the direct form prediction
242 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
243 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
244 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
248 static av_cold void dprint_specific_config(ALSDecContext *ctx)
251 AVCodecContext *avctx = ctx->avctx;
252 ALSSpecificConfig *sconf = &ctx->sconf;
254 av_dlog(avctx, "resolution = %i\n", sconf->resolution);
255 av_dlog(avctx, "floating = %i\n", sconf->floating);
256 av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
257 av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
258 av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
259 av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
260 av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
261 av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
262 av_dlog(avctx, "max_order = %i\n", sconf->max_order);
263 av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
264 av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
265 av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
266 av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
267 av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
268 av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
269 av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
270 av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
271 av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
276 /** Read an ALSSpecificConfig from a buffer into the output struct.
278 static av_cold int read_specific_config(ALSDecContext *ctx)
282 int i, config_offset;
283 MPEG4AudioConfig m4ac;
284 ALSSpecificConfig *sconf = &ctx->sconf;
285 AVCodecContext *avctx = ctx->avctx;
286 uint32_t als_id, header_size, trailer_size;
289 if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0)
292 config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
293 avctx->extradata_size * 8, 1);
295 if (config_offset < 0)
296 return AVERROR_INVALIDDATA;
298 skip_bits_long(&gb, config_offset);
300 if (get_bits_left(&gb) < (30 << 3))
301 return AVERROR_INVALIDDATA;
303 // read the fixed items
304 als_id = get_bits_long(&gb, 32);
305 avctx->sample_rate = m4ac.sample_rate;
306 skip_bits_long(&gb, 32); // sample rate already known
307 sconf->samples = get_bits_long(&gb, 32);
308 avctx->channels = m4ac.channels;
309 skip_bits(&gb, 16); // number of channels already known
310 skip_bits(&gb, 3); // skip file_type
311 sconf->resolution = get_bits(&gb, 3);
312 sconf->floating = get_bits1(&gb);
313 sconf->msb_first = get_bits1(&gb);
314 sconf->frame_length = get_bits(&gb, 16) + 1;
315 sconf->ra_distance = get_bits(&gb, 8);
316 sconf->ra_flag = get_bits(&gb, 2);
317 sconf->adapt_order = get_bits1(&gb);
318 sconf->coef_table = get_bits(&gb, 2);
319 sconf->long_term_prediction = get_bits1(&gb);
320 sconf->max_order = get_bits(&gb, 10);
321 sconf->block_switching = get_bits(&gb, 2);
322 sconf->bgmc = get_bits1(&gb);
323 sconf->sb_part = get_bits1(&gb);
324 sconf->joint_stereo = get_bits1(&gb);
325 sconf->mc_coding = get_bits1(&gb);
326 sconf->chan_config = get_bits1(&gb);
327 sconf->chan_sort = get_bits1(&gb);
328 sconf->crc_enabled = get_bits1(&gb);
329 sconf->rlslms = get_bits1(&gb);
330 skip_bits(&gb, 5); // skip 5 reserved bits
331 skip_bits1(&gb); // skip aux_data_enabled
334 // check for ALSSpecificConfig struct
335 if (als_id != MKBETAG('A','L','S','\0'))
336 return AVERROR_INVALIDDATA;
338 ctx->cur_frame_length = sconf->frame_length;
340 // read channel config
341 if (sconf->chan_config)
342 sconf->chan_config_info = get_bits(&gb, 16);
343 // TODO: use this to set avctx->channel_layout
346 // read channel sorting
347 if (sconf->chan_sort && avctx->channels > 1) {
348 int chan_pos_bits = av_ceil_log2(avctx->channels);
349 int bits_needed = avctx->channels * chan_pos_bits + 7;
350 if (get_bits_left(&gb) < bits_needed)
351 return AVERROR_INVALIDDATA;
353 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
354 return AVERROR(ENOMEM);
358 for (i = 0; i < avctx->channels; i++) {
361 idx = get_bits(&gb, chan_pos_bits);
362 if (idx >= avctx->channels) {
363 av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n");
367 sconf->chan_pos[idx] = i;
374 // read fixed header and trailer sizes,
375 // if size = 0xFFFFFFFF then there is no data field!
376 if (get_bits_left(&gb) < 64)
377 return AVERROR_INVALIDDATA;
379 header_size = get_bits_long(&gb, 32);
380 trailer_size = get_bits_long(&gb, 32);
381 if (header_size == 0xFFFFFFFF)
383 if (trailer_size == 0xFFFFFFFF)
386 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
389 // skip the header and trailer data
390 if (get_bits_left(&gb) < ht_size)
391 return AVERROR_INVALIDDATA;
393 if (ht_size > INT32_MAX)
394 return AVERROR_PATCHWELCOME;
396 skip_bits_long(&gb, ht_size);
399 // initialize CRC calculation
400 if (sconf->crc_enabled) {
401 if (get_bits_left(&gb) < 32)
402 return AVERROR_INVALIDDATA;
404 if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
405 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
406 ctx->crc = 0xFFFFFFFF;
407 ctx->crc_org = ~get_bits_long(&gb, 32);
409 skip_bits_long(&gb, 32);
413 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
415 dprint_specific_config(ctx);
421 /** Check the ALSSpecificConfig for unsupported features.
423 static int check_specific_config(ALSDecContext *ctx)
425 ALSSpecificConfig *sconf = &ctx->sconf;
428 // report unsupported feature and set error value
429 #define MISSING_ERR(cond, str, errval) \
432 avpriv_report_missing_feature(ctx->avctx, \
438 MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
439 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
445 /** Parse the bs_info field to extract the block partitioning used in
446 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
448 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
449 unsigned int div, unsigned int **div_blocks,
450 unsigned int *num_blocks)
452 if (n < 31 && ((bs_info << n) & 0x40000000)) {
453 // if the level is valid and the investigated bit n is set
454 // then recursively check both children at bits (2n+1) and (2n+2)
457 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
458 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
460 // else the bit is not set or the last level has been reached
461 // (bit implicitly not set)
469 /** Read and decode a Rice codeword.
471 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
473 int max = get_bits_left(gb) - k;
474 int q = get_unary(gb, 0, max);
475 int r = k ? get_bits1(gb) : !(q & 1);
479 q += get_bits_long(gb, k - 1);
487 /** Convert PARCOR coefficient k to direct filter coefficient.
489 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
493 for (i = 0, j = k - 1; i < j; i++, j--) {
494 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
495 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
499 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
505 /** Read block switching field if necessary and set actual block sizes.
506 * Also assure that the block sizes of the last frame correspond to the
507 * actual number of samples.
509 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
512 ALSSpecificConfig *sconf = &ctx->sconf;
513 GetBitContext *gb = &ctx->gb;
514 unsigned int *ptr_div_blocks = div_blocks;
517 if (sconf->block_switching) {
518 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
519 *bs_info = get_bits_long(gb, bs_info_len);
520 *bs_info <<= (32 - bs_info_len);
524 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
526 // The last frame may have an overdetermined block structure given in
527 // the bitstream. In that case the defined block structure would need
528 // more samples than available to be consistent.
529 // The block structure is actually used but the block sizes are adapted
530 // to fit the actual number of available samples.
531 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
532 // This results in the actual block sizes: 2 2 1 0.
533 // This is not specified in 14496-3 but actually done by the reference
534 // codec RM22 revision 2.
535 // This appears to happen in case of an odd number of samples in the last
536 // frame which is actually not allowed by the block length switching part
538 // The ALS conformance files feature an odd number of samples in the last
541 for (b = 0; b < ctx->num_blocks; b++)
542 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
544 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
545 unsigned int remaining = ctx->cur_frame_length;
547 for (b = 0; b < ctx->num_blocks; b++) {
548 if (remaining <= div_blocks[b]) {
549 div_blocks[b] = remaining;
550 ctx->num_blocks = b + 1;
554 remaining -= div_blocks[b];
560 /** Read the block data for a constant block
562 static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
564 ALSSpecificConfig *sconf = &ctx->sconf;
565 AVCodecContext *avctx = ctx->avctx;
566 GetBitContext *gb = &ctx->gb;
568 if (bd->block_length <= 0)
569 return AVERROR_INVALIDDATA;
571 *bd->raw_samples = 0;
572 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
573 bd->js_blocks = get_bits1(gb);
575 // skip 5 reserved bits
578 if (*bd->const_block) {
579 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
580 *bd->raw_samples = get_sbits_long(gb, const_val_bits);
583 // ensure constant block decoding by reusing this field
584 *bd->const_block = 1;
590 /** Decode the block data for a constant block
592 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
594 int smp = bd->block_length - 1;
595 int32_t val = *bd->raw_samples;
596 int32_t *dst = bd->raw_samples + 1;
598 // write raw samples into buffer
604 /** Read the block data for a non-constant block
606 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
608 ALSSpecificConfig *sconf = &ctx->sconf;
609 AVCodecContext *avctx = ctx->avctx;
610 GetBitContext *gb = &ctx->gb;
614 unsigned int sub_blocks, log2_sub_blocks, sb_length;
615 unsigned int start = 0;
616 unsigned int opt_order;
618 int32_t *quant_cof = bd->quant_cof;
619 int32_t *current_res;
622 // ensure variable block decoding by reusing this field
623 *bd->const_block = 0;
626 bd->js_blocks = get_bits1(gb);
628 opt_order = *bd->opt_order;
630 // determine the number of subblocks for entropy decoding
631 if (!sconf->bgmc && !sconf->sb_part) {
634 if (sconf->bgmc && sconf->sb_part)
635 log2_sub_blocks = get_bits(gb, 2);
637 log2_sub_blocks = 2 * get_bits1(gb);
640 sub_blocks = 1 << log2_sub_blocks;
642 // do not continue in case of a damaged stream since
643 // block_length must be evenly divisible by sub_blocks
644 if (bd->block_length & (sub_blocks - 1)) {
645 av_log(avctx, AV_LOG_WARNING,
646 "Block length is not evenly divisible by the number of subblocks.\n");
647 return AVERROR_INVALIDDATA;
650 sb_length = bd->block_length >> log2_sub_blocks;
653 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
654 for (k = 1; k < sub_blocks; k++)
655 s[k] = s[k - 1] + decode_rice(gb, 2);
657 for (k = 0; k < sub_blocks; k++) {
662 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
663 for (k = 1; k < sub_blocks; k++)
664 s[k] = s[k - 1] + decode_rice(gb, 0);
666 for (k = 1; k < sub_blocks; k++)
668 av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
669 return AVERROR_INVALIDDATA;
673 *bd->shift_lsbs = get_bits(gb, 4) + 1;
675 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
678 if (!sconf->rlslms) {
679 if (sconf->adapt_order) {
680 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
681 2, sconf->max_order + 1));
682 *bd->opt_order = get_bits(gb, opt_order_length);
683 if (*bd->opt_order > sconf->max_order) {
684 *bd->opt_order = sconf->max_order;
685 av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
686 return AVERROR_INVALIDDATA;
689 *bd->opt_order = sconf->max_order;
691 if (*bd->opt_order > bd->block_length) {
692 *bd->opt_order = bd->block_length;
693 av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
694 return AVERROR_INVALIDDATA;
696 opt_order = *bd->opt_order;
701 if (sconf->coef_table == 3) {
704 // read coefficient 0
705 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
707 // read coefficient 1
709 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
711 // read coefficients 2 to opt_order
712 for (k = 2; k < opt_order; k++)
713 quant_cof[k] = get_bits(gb, 7);
718 // read coefficient 0 to 19
719 k_max = FFMIN(opt_order, 20);
720 for (k = 0; k < k_max; k++) {
721 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
722 int offset = parcor_rice_table[sconf->coef_table][k][0];
723 quant_cof[k] = decode_rice(gb, rice_param) + offset;
724 if (quant_cof[k] < -64 || quant_cof[k] > 63) {
725 av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range.\n", quant_cof[k]);
726 return AVERROR_INVALIDDATA;
730 // read coefficients 20 to 126
731 k_max = FFMIN(opt_order, 127);
732 for (; k < k_max; k++)
733 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
735 // read coefficients 127 to opt_order
736 for (; k < opt_order; k++)
737 quant_cof[k] = decode_rice(gb, 1);
739 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
742 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
745 for (k = 2; k < opt_order; k++)
746 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
750 // read LTP gain and lag values
751 if (sconf->long_term_prediction) {
752 *bd->use_ltp = get_bits1(gb);
757 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
758 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
760 r = get_unary(gb, 0, 3);
762 bd->ltp_gain[2] = ltp_gain_values[r][c];
764 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
765 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
767 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
768 *bd->ltp_lag += FFMAX(4, opt_order + 1);
772 // read first value and residuals in case of a random access block
775 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
777 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
779 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
781 start = FFMIN(opt_order, 3);
784 // read all residuals
788 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
790 // read most significant bits
795 ff_bgmc_decode_init(gb, &high, &low, &value);
797 current_res = bd->raw_samples + start;
799 for (sb = 0; sb < sub_blocks; sb++) {
800 unsigned int sb_len = sb_length - (sb ? 0 : start);
802 k [sb] = s[sb] > b ? s[sb] - b : 0;
803 delta[sb] = 5 - s[sb] + k[sb];
805 ff_bgmc_decode(gb, sb_len, current_res,
806 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
808 current_res += sb_len;
811 ff_bgmc_decode_end(gb);
814 // read least significant bits and tails
815 current_res = bd->raw_samples + start;
817 for (sb = 0; sb < sub_blocks; sb++, start = 0) {
818 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
819 unsigned int cur_k = k[sb];
820 unsigned int cur_s = s[sb];
822 for (; start < sb_length; start++) {
823 int32_t res = *current_res;
825 if (res == cur_tail_code) {
826 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
829 res = decode_rice(gb, cur_s);
832 res += (max_msb ) << cur_k;
834 res -= (max_msb - 1) << cur_k;
837 if (res > cur_tail_code)
847 res |= get_bits_long(gb, cur_k);
851 *current_res++ = res;
855 current_res = bd->raw_samples + start;
857 for (sb = 0; sb < sub_blocks; sb++, start = 0)
858 for (; start < sb_length; start++)
859 *current_res++ = decode_rice(gb, s[sb]);
862 if (!sconf->mc_coding || ctx->js_switch)
869 /** Decode the block data for a non-constant block
871 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
873 ALSSpecificConfig *sconf = &ctx->sconf;
874 unsigned int block_length = bd->block_length;
875 unsigned int smp = 0;
877 int opt_order = *bd->opt_order;
880 int32_t *quant_cof = bd->quant_cof;
881 int32_t *lpc_cof = bd->lpc_cof;
882 int32_t *raw_samples = bd->raw_samples;
883 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
884 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
886 // reverse long-term prediction
890 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
891 int center = ltp_smp - *bd->ltp_lag;
892 int begin = FFMAX(0, center - 2);
893 int end = center + 3;
894 int tab = 5 - (end - begin);
899 for (base = begin; base < end; base++, tab++)
900 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
902 raw_samples[ltp_smp] += y >> 7;
906 // reconstruct all samples from residuals
908 for (smp = 0; smp < opt_order; smp++) {
911 for (sb = 0; sb < smp; sb++)
912 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
914 *raw_samples++ -= y >> 20;
915 parcor_to_lpc(smp, quant_cof, lpc_cof);
918 for (k = 0; k < opt_order; k++)
919 parcor_to_lpc(k, quant_cof, lpc_cof);
921 // store previous samples in case that they have to be altered
922 if (*bd->store_prev_samples)
923 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
924 sizeof(*bd->prev_raw_samples) * sconf->max_order);
926 // reconstruct difference signal for prediction (joint-stereo)
927 if (bd->js_blocks && bd->raw_other) {
928 int32_t *left, *right;
930 if (bd->raw_other > raw_samples) { // D = R - L
932 right = bd->raw_other;
933 } else { // D = R - L
934 left = bd->raw_other;
938 for (sb = -1; sb >= -sconf->max_order; sb--)
939 raw_samples[sb] = right[sb] - left[sb];
942 // reconstruct shifted signal
944 for (sb = -1; sb >= -sconf->max_order; sb--)
945 raw_samples[sb] >>= *bd->shift_lsbs;
948 // reverse linear prediction coefficients for efficiency
949 lpc_cof = lpc_cof + opt_order;
951 for (sb = 0; sb < opt_order; sb++)
952 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
954 // reconstruct raw samples
955 raw_samples = bd->raw_samples + smp;
956 lpc_cof = lpc_cof_reversed + opt_order;
958 for (; raw_samples < raw_samples_end; raw_samples++) {
961 for (sb = -opt_order; sb < 0; sb++)
962 y += MUL64(lpc_cof[sb], raw_samples[sb]);
964 *raw_samples -= y >> 20;
967 raw_samples = bd->raw_samples;
969 // restore previous samples in case that they have been altered
970 if (*bd->store_prev_samples)
971 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
972 sizeof(*raw_samples) * sconf->max_order);
978 /** Read the block data.
980 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
983 GetBitContext *gb = &ctx->gb;
986 // read block type flag and read the samples accordingly
988 ret = read_var_block_data(ctx, bd);
990 ret = read_const_block_data(ctx, bd);
997 /** Decode the block data.
999 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1004 // read block type flag and read the samples accordingly
1005 if (*bd->const_block)
1006 decode_const_block_data(ctx, bd);
1008 ret = decode_var_block_data(ctx, bd); // always return 0
1013 // TODO: read RLSLMS extension data
1015 if (*bd->shift_lsbs)
1016 for (smp = 0; smp < bd->block_length; smp++)
1017 bd->raw_samples[smp] <<= *bd->shift_lsbs;
1023 /** Read and decode block data successively.
1025 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1029 if ((ret = read_block(ctx, bd)) < 0)
1032 return decode_block(ctx, bd);
1036 /** Compute the number of samples left to decode for the current frame and
1037 * sets these samples to zero.
1039 static void zero_remaining(unsigned int b, unsigned int b_max,
1040 const unsigned int *div_blocks, int32_t *buf)
1042 unsigned int count = 0;
1045 count += div_blocks[b++];
1048 memset(buf, 0, sizeof(*buf) * count);
1052 /** Decode blocks independently.
1054 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1055 unsigned int c, const unsigned int *div_blocks,
1056 unsigned int *js_blocks)
1060 ALSBlockData bd = { 0 };
1062 bd.ra_block = ra_frame;
1063 bd.const_block = ctx->const_block;
1064 bd.shift_lsbs = ctx->shift_lsbs;
1065 bd.opt_order = ctx->opt_order;
1066 bd.store_prev_samples = ctx->store_prev_samples;
1067 bd.use_ltp = ctx->use_ltp;
1068 bd.ltp_lag = ctx->ltp_lag;
1069 bd.ltp_gain = ctx->ltp_gain[0];
1070 bd.quant_cof = ctx->quant_cof[0];
1071 bd.lpc_cof = ctx->lpc_cof[0];
1072 bd.prev_raw_samples = ctx->prev_raw_samples;
1073 bd.raw_samples = ctx->raw_samples[c];
1076 for (b = 0; b < ctx->num_blocks; b++) {
1077 bd.block_length = div_blocks[b];
1079 if ((ret = read_decode_block(ctx, &bd)) < 0) {
1080 // damaged block, write zero for the rest of the frame
1081 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1084 bd.raw_samples += div_blocks[b];
1092 /** Decode blocks dependently.
1094 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1095 unsigned int c, const unsigned int *div_blocks,
1096 unsigned int *js_blocks)
1098 ALSSpecificConfig *sconf = &ctx->sconf;
1099 unsigned int offset = 0;
1102 ALSBlockData bd[2] = { { 0 } };
1104 bd[0].ra_block = ra_frame;
1105 bd[0].const_block = ctx->const_block;
1106 bd[0].shift_lsbs = ctx->shift_lsbs;
1107 bd[0].opt_order = ctx->opt_order;
1108 bd[0].store_prev_samples = ctx->store_prev_samples;
1109 bd[0].use_ltp = ctx->use_ltp;
1110 bd[0].ltp_lag = ctx->ltp_lag;
1111 bd[0].ltp_gain = ctx->ltp_gain[0];
1112 bd[0].quant_cof = ctx->quant_cof[0];
1113 bd[0].lpc_cof = ctx->lpc_cof[0];
1114 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1115 bd[0].js_blocks = *js_blocks;
1117 bd[1].ra_block = ra_frame;
1118 bd[1].const_block = ctx->const_block;
1119 bd[1].shift_lsbs = ctx->shift_lsbs;
1120 bd[1].opt_order = ctx->opt_order;
1121 bd[1].store_prev_samples = ctx->store_prev_samples;
1122 bd[1].use_ltp = ctx->use_ltp;
1123 bd[1].ltp_lag = ctx->ltp_lag;
1124 bd[1].ltp_gain = ctx->ltp_gain[0];
1125 bd[1].quant_cof = ctx->quant_cof[0];
1126 bd[1].lpc_cof = ctx->lpc_cof[0];
1127 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1128 bd[1].js_blocks = *(js_blocks + 1);
1130 // decode all blocks
1131 for (b = 0; b < ctx->num_blocks; b++) {
1134 bd[0].block_length = div_blocks[b];
1135 bd[1].block_length = div_blocks[b];
1137 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1138 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1140 bd[0].raw_other = bd[1].raw_samples;
1141 bd[1].raw_other = bd[0].raw_samples;
1143 if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1144 (ret = read_decode_block(ctx, &bd[1])) < 0)
1147 // reconstruct joint-stereo blocks
1148 if (bd[0].js_blocks) {
1149 if (bd[1].js_blocks)
1150 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1152 for (s = 0; s < div_blocks[b]; s++)
1153 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1154 } else if (bd[1].js_blocks) {
1155 for (s = 0; s < div_blocks[b]; s++)
1156 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1159 offset += div_blocks[b];
1164 // store carryover raw samples,
1165 // the others channel raw samples are stored by the calling function.
1166 memmove(ctx->raw_samples[c] - sconf->max_order,
1167 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1168 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1172 // damaged block, write zero for the rest of the frame
1173 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1174 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1178 static inline int als_weighting(GetBitContext *gb, int k, int off)
1180 int idx = av_clip(decode_rice(gb, k) + off,
1181 0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1182 return mcc_weightings[idx];
1185 /** Read the channel data.
1187 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1189 GetBitContext *gb = &ctx->gb;
1190 ALSChannelData *current = cd;
1191 unsigned int channels = ctx->avctx->channels;
1194 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1195 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1197 if (current->master_channel >= channels) {
1198 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n");
1199 return AVERROR_INVALIDDATA;
1202 if (current->master_channel != c) {
1203 current->time_diff_flag = get_bits1(gb);
1204 current->weighting[0] = als_weighting(gb, 1, 16);
1205 current->weighting[1] = als_weighting(gb, 2, 14);
1206 current->weighting[2] = als_weighting(gb, 1, 16);
1208 if (current->time_diff_flag) {
1209 current->weighting[3] = als_weighting(gb, 1, 16);
1210 current->weighting[4] = als_weighting(gb, 1, 16);
1211 current->weighting[5] = als_weighting(gb, 1, 16);
1213 current->time_diff_sign = get_bits1(gb);
1214 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1222 if (entries == channels) {
1223 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n");
1224 return AVERROR_INVALIDDATA;
1232 /** Recursively reverts the inter-channel correlation for a block.
1234 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1235 ALSChannelData **cd, int *reverted,
1236 unsigned int offset, int c)
1238 ALSChannelData *ch = cd[c];
1239 unsigned int dep = 0;
1240 unsigned int channels = ctx->avctx->channels;
1247 while (dep < channels && !ch[dep].stop_flag) {
1248 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1249 ch[dep].master_channel);
1254 if (dep == channels) {
1255 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1256 return AVERROR_INVALIDDATA;
1259 bd->const_block = ctx->const_block + c;
1260 bd->shift_lsbs = ctx->shift_lsbs + c;
1261 bd->opt_order = ctx->opt_order + c;
1262 bd->store_prev_samples = ctx->store_prev_samples + c;
1263 bd->use_ltp = ctx->use_ltp + c;
1264 bd->ltp_lag = ctx->ltp_lag + c;
1265 bd->ltp_gain = ctx->ltp_gain[c];
1266 bd->lpc_cof = ctx->lpc_cof[c];
1267 bd->quant_cof = ctx->quant_cof[c];
1268 bd->raw_samples = ctx->raw_samples[c] + offset;
1270 for (dep = 0; !ch[dep].stop_flag; dep++) {
1272 unsigned int begin = 1;
1273 unsigned int end = bd->block_length - 1;
1275 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1277 if (ch[dep].master_channel == c)
1280 if (ch[dep].time_diff_flag) {
1281 int t = ch[dep].time_diff_index;
1283 if (ch[dep].time_diff_sign) {
1290 for (smp = begin; smp < end; smp++) {
1292 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1293 MUL64(ch[dep].weighting[1], master[smp ]) +
1294 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1295 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1296 MUL64(ch[dep].weighting[4], master[smp + t]) +
1297 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1299 bd->raw_samples[smp] += y >> 7;
1302 for (smp = begin; smp < end; smp++) {
1304 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1305 MUL64(ch[dep].weighting[1], master[smp ]) +
1306 MUL64(ch[dep].weighting[2], master[smp + 1]);
1308 bd->raw_samples[smp] += y >> 7;
1317 /** Read the frame data.
1319 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1321 ALSSpecificConfig *sconf = &ctx->sconf;
1322 AVCodecContext *avctx = ctx->avctx;
1323 GetBitContext *gb = &ctx->gb;
1324 unsigned int div_blocks[32]; ///< block sizes.
1326 unsigned int js_blocks[2];
1327 uint32_t bs_info = 0;
1330 // skip the size of the ra unit if present in the frame
1331 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1332 skip_bits_long(gb, 32);
1334 if (sconf->mc_coding && sconf->joint_stereo) {
1335 ctx->js_switch = get_bits1(gb);
1339 if (!sconf->mc_coding || ctx->js_switch) {
1340 int independent_bs = !sconf->joint_stereo;
1342 for (c = 0; c < avctx->channels; c++) {
1346 get_block_sizes(ctx, div_blocks, &bs_info);
1348 // if joint_stereo and block_switching is set, independent decoding
1349 // is signaled via the first bit of bs_info
1350 if (sconf->joint_stereo && sconf->block_switching)
1354 // if this is the last channel, it has to be decoded independently
1355 if (c == avctx->channels - 1)
1358 if (independent_bs) {
1359 ret = decode_blocks_ind(ctx, ra_frame, c,
1360 div_blocks, js_blocks);
1365 ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1372 // store carryover raw samples
1373 memmove(ctx->raw_samples[c] - sconf->max_order,
1374 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1375 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1377 } else { // multi-channel coding
1378 ALSBlockData bd = { 0 };
1380 int *reverted_channels = ctx->reverted_channels;
1381 unsigned int offset = 0;
1383 for (c = 0; c < avctx->channels; c++)
1384 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1385 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n");
1386 return AVERROR_INVALIDDATA;
1389 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1391 bd.ra_block = ra_frame;
1392 bd.prev_raw_samples = ctx->prev_raw_samples;
1394 get_block_sizes(ctx, div_blocks, &bs_info);
1396 for (b = 0; b < ctx->num_blocks; b++) {
1397 bd.block_length = div_blocks[b];
1398 if (bd.block_length <= 0) {
1399 av_log(ctx->avctx, AV_LOG_WARNING,
1400 "Invalid block length %d in channel data!\n", bd.block_length);
1404 for (c = 0; c < avctx->channels; c++) {
1405 bd.const_block = ctx->const_block + c;
1406 bd.shift_lsbs = ctx->shift_lsbs + c;
1407 bd.opt_order = ctx->opt_order + c;
1408 bd.store_prev_samples = ctx->store_prev_samples + c;
1409 bd.use_ltp = ctx->use_ltp + c;
1410 bd.ltp_lag = ctx->ltp_lag + c;
1411 bd.ltp_gain = ctx->ltp_gain[c];
1412 bd.lpc_cof = ctx->lpc_cof[c];
1413 bd.quant_cof = ctx->quant_cof[c];
1414 bd.raw_samples = ctx->raw_samples[c] + offset;
1415 bd.raw_other = NULL;
1417 if ((ret = read_block(ctx, &bd)) < 0)
1419 if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1423 for (c = 0; c < avctx->channels; c++) {
1424 ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1425 reverted_channels, offset, c);
1429 for (c = 0; c < avctx->channels; c++) {
1430 bd.const_block = ctx->const_block + c;
1431 bd.shift_lsbs = ctx->shift_lsbs + c;
1432 bd.opt_order = ctx->opt_order + c;
1433 bd.store_prev_samples = ctx->store_prev_samples + c;
1434 bd.use_ltp = ctx->use_ltp + c;
1435 bd.ltp_lag = ctx->ltp_lag + c;
1436 bd.ltp_gain = ctx->ltp_gain[c];
1437 bd.lpc_cof = ctx->lpc_cof[c];
1438 bd.quant_cof = ctx->quant_cof[c];
1439 bd.raw_samples = ctx->raw_samples[c] + offset;
1441 if ((ret = decode_block(ctx, &bd)) < 0)
1445 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1446 offset += div_blocks[b];
1450 // store carryover raw samples
1451 for (c = 0; c < avctx->channels; c++)
1452 memmove(ctx->raw_samples[c] - sconf->max_order,
1453 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1454 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1457 // TODO: read_diff_float_data
1463 /** Decode an ALS frame.
1465 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1468 ALSDecContext *ctx = avctx->priv_data;
1469 AVFrame *frame = data;
1470 ALSSpecificConfig *sconf = &ctx->sconf;
1471 const uint8_t *buffer = avpkt->data;
1472 int buffer_size = avpkt->size;
1473 int invalid_frame, ret;
1474 unsigned int c, sample, ra_frame, bytes_read, shift;
1476 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1478 // In the case that the distance between random access frames is set to zero
1479 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1480 // For the first frame, if prediction is used, all samples used from the
1481 // previous frame are assumed to be zero.
1482 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1484 // the last frame to decode might have a different length
1485 if (sconf->samples != 0xFFFFFFFF)
1486 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1487 sconf->frame_length);
1489 ctx->cur_frame_length = sconf->frame_length;
1491 // decode the frame data
1492 if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1493 av_log(ctx->avctx, AV_LOG_WARNING,
1494 "Reading frame data failed. Skipping RA unit.\n");
1498 /* get output buffer */
1499 frame->nb_samples = ctx->cur_frame_length;
1500 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1503 // transform decoded frame into output format
1504 #define INTERLEAVE_OUTPUT(bps) \
1506 int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1507 shift = bps - ctx->avctx->bits_per_raw_sample; \
1508 if (!ctx->cs_switch) { \
1509 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1510 for (c = 0; c < avctx->channels; c++) \
1511 *dest++ = ctx->raw_samples[c][sample] << shift; \
1513 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1514 for (c = 0; c < avctx->channels; c++) \
1515 *dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] << shift; \
1519 if (ctx->avctx->bits_per_raw_sample <= 16) {
1520 INTERLEAVE_OUTPUT(16)
1522 INTERLEAVE_OUTPUT(32)
1526 if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1527 int swap = HAVE_BIGENDIAN != sconf->msb_first;
1529 if (ctx->avctx->bits_per_raw_sample == 24) {
1530 int32_t *src = (int32_t *)frame->data[0];
1533 sample < ctx->cur_frame_length * avctx->channels;
1538 v = av_bswap32(src[sample]);
1541 if (!HAVE_BIGENDIAN)
1544 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1547 uint8_t *crc_source;
1550 if (ctx->avctx->bits_per_raw_sample <= 16) {
1551 int16_t *src = (int16_t*) frame->data[0];
1552 int16_t *dest = (int16_t*) ctx->crc_buffer;
1554 sample < ctx->cur_frame_length * avctx->channels;
1556 *dest++ = av_bswap16(src[sample]);
1558 ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1559 (uint32_t *)frame->data[0],
1560 ctx->cur_frame_length * avctx->channels);
1562 crc_source = ctx->crc_buffer;
1564 crc_source = frame->data[0];
1567 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1568 ctx->cur_frame_length * avctx->channels *
1569 av_get_bytes_per_sample(avctx->sample_fmt));
1573 // check CRC sums if this is the last frame
1574 if (ctx->cur_frame_length != sconf->frame_length &&
1575 ctx->crc_org != ctx->crc) {
1576 av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1577 if (avctx->err_recognition & AV_EF_EXPLODE)
1578 return AVERROR_INVALIDDATA;
1584 bytes_read = invalid_frame ? buffer_size :
1585 (get_bits_count(&ctx->gb) + 7) >> 3;
1591 /** Uninitialize the ALS decoder.
1593 static av_cold int decode_end(AVCodecContext *avctx)
1595 ALSDecContext *ctx = avctx->priv_data;
1597 av_freep(&ctx->sconf.chan_pos);
1599 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1601 av_freep(&ctx->const_block);
1602 av_freep(&ctx->shift_lsbs);
1603 av_freep(&ctx->opt_order);
1604 av_freep(&ctx->store_prev_samples);
1605 av_freep(&ctx->use_ltp);
1606 av_freep(&ctx->ltp_lag);
1607 av_freep(&ctx->ltp_gain);
1608 av_freep(&ctx->ltp_gain_buffer);
1609 av_freep(&ctx->quant_cof);
1610 av_freep(&ctx->lpc_cof);
1611 av_freep(&ctx->quant_cof_buffer);
1612 av_freep(&ctx->lpc_cof_buffer);
1613 av_freep(&ctx->lpc_cof_reversed_buffer);
1614 av_freep(&ctx->prev_raw_samples);
1615 av_freep(&ctx->raw_samples);
1616 av_freep(&ctx->raw_buffer);
1617 av_freep(&ctx->chan_data);
1618 av_freep(&ctx->chan_data_buffer);
1619 av_freep(&ctx->reverted_channels);
1620 av_freep(&ctx->crc_buffer);
1626 /** Initialize the ALS decoder.
1628 static av_cold int decode_init(AVCodecContext *avctx)
1631 unsigned int channel_size;
1632 int num_buffers, ret;
1633 ALSDecContext *ctx = avctx->priv_data;
1634 ALSSpecificConfig *sconf = &ctx->sconf;
1637 if (!avctx->extradata) {
1638 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1639 return AVERROR_INVALIDDATA;
1642 if ((ret = read_specific_config(ctx)) < 0) {
1643 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1647 if ((ret = check_specific_config(ctx)) < 0) {
1652 ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1656 if (sconf->floating) {
1657 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1658 avctx->bits_per_raw_sample = 32;
1660 avctx->sample_fmt = sconf->resolution > 1
1661 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1662 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1665 // set maximum Rice parameter for progressive decoding based on resolution
1666 // This is not specified in 14496-3 but actually done by the reference
1667 // codec RM22 revision 2.
1668 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1670 // set lag value for long-term prediction
1671 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1672 (avctx->sample_rate >= 192000);
1674 // allocate quantized parcor coefficient buffer
1675 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1677 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1678 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1679 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1680 num_buffers * sconf->max_order);
1681 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1682 num_buffers * sconf->max_order);
1683 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1686 if (!ctx->quant_cof || !ctx->lpc_cof ||
1687 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1688 !ctx->lpc_cof_reversed_buffer) {
1689 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1690 ret = AVERROR(ENOMEM);
1694 // assign quantized parcor coefficient buffers
1695 for (c = 0; c < num_buffers; c++) {
1696 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1697 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1700 // allocate and assign lag and gain data buffer for ltp mode
1701 ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1702 ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1703 ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1704 ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1705 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1706 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1707 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1708 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1711 if (!ctx->const_block || !ctx->shift_lsbs ||
1712 !ctx->opt_order || !ctx->store_prev_samples ||
1713 !ctx->use_ltp || !ctx->ltp_lag ||
1714 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1715 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1716 ret = AVERROR(ENOMEM);
1720 for (c = 0; c < num_buffers; c++)
1721 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1723 // allocate and assign channel data buffer for mcc mode
1724 if (sconf->mc_coding) {
1725 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1726 num_buffers * num_buffers);
1727 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1729 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1732 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1733 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1734 ret = AVERROR(ENOMEM);
1738 for (c = 0; c < num_buffers; c++)
1739 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1741 ctx->chan_data = NULL;
1742 ctx->chan_data_buffer = NULL;
1743 ctx->reverted_channels = NULL;
1746 channel_size = sconf->frame_length + sconf->max_order;
1748 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1749 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1750 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1752 // allocate previous raw sample buffer
1753 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1754 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1755 ret = AVERROR(ENOMEM);
1759 // assign raw samples buffers
1760 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1761 for (c = 1; c < avctx->channels; c++)
1762 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1764 // allocate crc buffer
1765 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1766 (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1767 ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1768 ctx->cur_frame_length *
1770 av_get_bytes_per_sample(avctx->sample_fmt));
1771 if (!ctx->crc_buffer) {
1772 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1773 ret = AVERROR(ENOMEM);
1778 ff_dsputil_init(&ctx->dsp, avctx);
1788 /** Flush (reset) the frame ID after seeking.
1790 static av_cold void flush(AVCodecContext *avctx)
1792 ALSDecContext *ctx = avctx->priv_data;
1798 AVCodec ff_als_decoder = {
1800 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1801 .type = AVMEDIA_TYPE_AUDIO,
1802 .id = AV_CODEC_ID_MP4ALS,
1803 .priv_data_size = sizeof(ALSDecContext),
1804 .init = decode_init,
1805 .close = decode_end,
1806 .decode = decode_frame,
1808 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,