3 * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
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_ googlemail.com>
35 #include "mpeg4audio.h"
36 #include "bytestream.h"
39 #include "libavutil/samplefmt.h"
40 #include "libavutil/crc.h"
44 /** Rice parameters and corresponding index offsets for decoding the
45 * indices of scaled PARCOR values. The table chosen is set globally
46 * by the encoder and stored in ALSSpecificConfig.
48 static const int8_t parcor_rice_table[3][20][2] = {
49 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
50 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
51 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
52 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
53 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
54 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
55 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
56 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
57 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
58 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
59 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
60 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
64 /** Scaled PARCOR values used for the first two PARCOR coefficients.
65 * To be indexed by the Rice coded indices.
66 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
67 * Actual values are divided by 32 in order to be stored in 16 bits.
69 static const int16_t parcor_scaled_values[] = {
70 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
71 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
72 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
73 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
74 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
75 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
76 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
77 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
78 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
79 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
80 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
81 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
82 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
83 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
84 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
85 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
86 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
87 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
88 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
89 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
90 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
91 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
92 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
93 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
94 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
95 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
96 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
97 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
98 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
99 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
100 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
101 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
105 /** Gain values of p(0) for long-term prediction.
106 * To be indexed by the Rice coded indices.
108 static const uint8_t ltp_gain_values [4][4] = {
116 /** Inter-channel weighting factors for multi-channel correlation.
117 * To be indexed by the Rice coded indices.
119 static const int16_t mcc_weightings[] = {
120 204, 192, 179, 166, 153, 140, 128, 115,
121 102, 89, 76, 64, 51, 38, 25, 12,
122 0, -12, -25, -38, -51, -64, -76, -89,
123 -102, -115, -128, -140, -153, -166, -179, -192
127 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
129 static const uint8_t tail_code[16][6] = {
130 { 74, 44, 25, 13, 7, 3},
131 { 68, 42, 24, 13, 7, 3},
132 { 58, 39, 23, 13, 7, 3},
133 {126, 70, 37, 19, 10, 5},
134 {132, 70, 37, 20, 10, 5},
135 {124, 70, 38, 20, 10, 5},
136 {120, 69, 37, 20, 11, 5},
137 {116, 67, 37, 20, 11, 5},
138 {108, 66, 36, 20, 10, 5},
139 {102, 62, 36, 20, 10, 5},
140 { 88, 58, 34, 19, 10, 5},
141 {162, 89, 49, 25, 13, 7},
142 {156, 87, 49, 26, 14, 7},
143 {150, 86, 47, 26, 14, 7},
144 {142, 84, 47, 26, 14, 7},
145 {131, 79, 46, 26, 14, 7}
157 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
158 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
159 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
160 int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
161 int frame_length; ///< frame length for each frame (last frame may differ)
162 int ra_distance; ///< distance between RA frames (in frames, 0...255)
163 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
164 int adapt_order; ///< adaptive order: 1 = on, 0 = off
165 int coef_table; ///< table index of Rice code parameters
166 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
167 int max_order; ///< maximum prediction order (0..1023)
168 int block_switching; ///< number of block switching levels
169 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
170 int sb_part; ///< sub-block partition
171 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
172 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
173 int chan_config; ///< indicates that a chan_config_info field is present
174 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
175 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
176 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
177 int *chan_pos; ///< original channel positions
178 int crc_enabled; ///< enable Cyclic Redundancy Checksum
193 AVCodecContext *avctx;
194 ALSSpecificConfig sconf;
197 const AVCRC *crc_table;
198 uint32_t crc_org; ///< CRC value of the original input data
199 uint32_t crc; ///< CRC value calculated from decoded data
200 unsigned int cur_frame_length; ///< length of the current frame to decode
201 unsigned int frame_id; ///< the frame ID / number of the current frame
202 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
203 unsigned int num_blocks; ///< number of blocks used in the current frame
204 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
205 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
206 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
207 int ltp_lag_length; ///< number of bits used for ltp lag value
208 int *const_block; ///< contains const_block flags for all channels
209 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
210 unsigned int *opt_order; ///< contains opt_order flags for all channels
211 int *store_prev_samples; ///< contains store_prev_samples flags for all channels
212 int *use_ltp; ///< contains use_ltp flags for all channels
213 int *ltp_lag; ///< contains ltp lag values for all channels
214 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
215 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
216 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
217 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
218 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
219 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
220 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
221 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
222 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
223 int *reverted_channels; ///< stores a flag for each reverted channel
224 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
225 int32_t **raw_samples; ///< decoded raw samples for each channel
226 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
227 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
232 unsigned int block_length; ///< number of samples within the block
233 unsigned int ra_block; ///< if true, this is a random access block
234 int *const_block; ///< if true, this is a constant value block
235 int js_blocks; ///< true if this block contains a difference signal
236 unsigned int *shift_lsbs; ///< shift of values for this block
237 unsigned int *opt_order; ///< prediction order of this block
238 int *store_prev_samples;///< if true, carryover samples have to be stored
239 int *use_ltp; ///< if true, long-term prediction is used
240 int *ltp_lag; ///< lag value for long-term prediction
241 int *ltp_gain; ///< gain values for ltp 5-tap filter
242 int32_t *quant_cof; ///< quantized parcor coefficients
243 int32_t *lpc_cof; ///< coefficients of the direct form prediction
244 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
245 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
246 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
250 static av_cold void dprint_specific_config(ALSDecContext *ctx)
253 AVCodecContext *avctx = ctx->avctx;
254 ALSSpecificConfig *sconf = &ctx->sconf;
256 av_dlog(avctx, "resolution = %i\n", sconf->resolution);
257 av_dlog(avctx, "floating = %i\n", sconf->floating);
258 av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
259 av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
260 av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
261 av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
262 av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
263 av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
264 av_dlog(avctx, "max_order = %i\n", sconf->max_order);
265 av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
266 av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
267 av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
268 av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
269 av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
270 av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
271 av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
272 av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
273 av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
278 /** Read an ALSSpecificConfig from a buffer into the output struct.
280 static av_cold int read_specific_config(ALSDecContext *ctx)
284 int i, config_offset;
285 MPEG4AudioConfig m4ac;
286 ALSSpecificConfig *sconf = &ctx->sconf;
287 AVCodecContext *avctx = ctx->avctx;
288 uint32_t als_id, header_size, trailer_size;
290 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
292 config_offset = ff_mpeg4audio_get_config(&m4ac, avctx->extradata,
293 avctx->extradata_size);
295 if (config_offset < 0)
298 skip_bits_long(&gb, config_offset);
300 if (get_bits_left(&gb) < (30 << 3))
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 knwon
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'))
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)
353 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
354 return AVERROR(ENOMEM);
356 for (i = 0; i < avctx->channels; i++)
357 sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
360 // TODO: use this to actually do channel sorting
362 sconf->chan_sort = 0;
366 // read fixed header and trailer sizes,
367 // if size = 0xFFFFFFFF then there is no data field!
368 if (get_bits_left(&gb) < 64)
371 header_size = get_bits_long(&gb, 32);
372 trailer_size = get_bits_long(&gb, 32);
373 if (header_size == 0xFFFFFFFF)
375 if (trailer_size == 0xFFFFFFFF)
378 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
381 // skip the header and trailer data
382 if (get_bits_left(&gb) < ht_size)
385 if (ht_size > INT32_MAX)
388 skip_bits_long(&gb, ht_size);
391 // initialize CRC calculation
392 if (sconf->crc_enabled) {
393 if (get_bits_left(&gb) < 32)
396 if (avctx->error_recognition >= FF_ER_CAREFUL) {
397 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
398 ctx->crc = 0xFFFFFFFF;
399 ctx->crc_org = ~get_bits_long(&gb, 32);
401 skip_bits_long(&gb, 32);
405 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
407 dprint_specific_config(ctx);
413 /** Check the ALSSpecificConfig for unsupported features.
415 static int check_specific_config(ALSDecContext *ctx)
417 ALSSpecificConfig *sconf = &ctx->sconf;
420 // report unsupported feature and set error value
421 #define MISSING_ERR(cond, str, errval) \
424 av_log_missing_feature(ctx->avctx, str, 0); \
429 MISSING_ERR(sconf->floating, "Floating point decoding", -1);
430 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
431 MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
437 /** Parse the bs_info field to extract the block partitioning used in
438 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
440 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
441 unsigned int div, unsigned int **div_blocks,
442 unsigned int *num_blocks)
444 if (n < 31 && ((bs_info << n) & 0x40000000)) {
445 // if the level is valid and the investigated bit n is set
446 // then recursively check both children at bits (2n+1) and (2n+2)
449 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
450 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
452 // else the bit is not set or the last level has been reached
453 // (bit implicitly not set)
461 /** Read and decode a Rice codeword.
463 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
465 int max = get_bits_left(gb) - k;
466 int q = get_unary(gb, 0, max);
467 int r = k ? get_bits1(gb) : !(q & 1);
471 q += get_bits_long(gb, k - 1);
479 /** Convert PARCOR coefficient k to direct filter coefficient.
481 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
485 for (i = 0, j = k - 1; i < j; i++, j--) {
486 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
487 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
491 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
497 /** Read block switching field if necessary and set actual block sizes.
498 * Also assure that the block sizes of the last frame correspond to the
499 * actual number of samples.
501 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
504 ALSSpecificConfig *sconf = &ctx->sconf;
505 GetBitContext *gb = &ctx->gb;
506 unsigned int *ptr_div_blocks = div_blocks;
509 if (sconf->block_switching) {
510 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
511 *bs_info = get_bits_long(gb, bs_info_len);
512 *bs_info <<= (32 - bs_info_len);
516 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
518 // The last frame may have an overdetermined block structure given in
519 // the bitstream. In that case the defined block structure would need
520 // more samples than available to be consistent.
521 // The block structure is actually used but the block sizes are adapted
522 // to fit the actual number of available samples.
523 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
524 // This results in the actual block sizes: 2 2 1 0.
525 // This is not specified in 14496-3 but actually done by the reference
526 // codec RM22 revision 2.
527 // This appears to happen in case of an odd number of samples in the last
528 // frame which is actually not allowed by the block length switching part
530 // The ALS conformance files feature an odd number of samples in the last
533 for (b = 0; b < ctx->num_blocks; b++)
534 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
536 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
537 unsigned int remaining = ctx->cur_frame_length;
539 for (b = 0; b < ctx->num_blocks; b++) {
540 if (remaining <= div_blocks[b]) {
541 div_blocks[b] = remaining;
542 ctx->num_blocks = b + 1;
546 remaining -= div_blocks[b];
552 /** Read the block data for a constant block
554 static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
556 ALSSpecificConfig *sconf = &ctx->sconf;
557 AVCodecContext *avctx = ctx->avctx;
558 GetBitContext *gb = &ctx->gb;
560 *bd->raw_samples = 0;
561 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
562 bd->js_blocks = get_bits1(gb);
564 // skip 5 reserved bits
567 if (*bd->const_block) {
568 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
569 *bd->raw_samples = get_sbits_long(gb, const_val_bits);
572 // ensure constant block decoding by reusing this field
573 *bd->const_block = 1;
577 /** Decode the block data for a constant block
579 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
581 int smp = bd->block_length - 1;
582 int32_t val = *bd->raw_samples;
583 int32_t *dst = bd->raw_samples + 1;
585 // write raw samples into buffer
591 /** Read the block data for a non-constant block
593 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
595 ALSSpecificConfig *sconf = &ctx->sconf;
596 AVCodecContext *avctx = ctx->avctx;
597 GetBitContext *gb = &ctx->gb;
601 unsigned int sub_blocks, log2_sub_blocks, sb_length;
602 unsigned int start = 0;
603 unsigned int opt_order;
605 int32_t *quant_cof = bd->quant_cof;
606 int32_t *current_res;
609 // ensure variable block decoding by reusing this field
610 *bd->const_block = 0;
613 bd->js_blocks = get_bits1(gb);
615 opt_order = *bd->opt_order;
617 // determine the number of subblocks for entropy decoding
618 if (!sconf->bgmc && !sconf->sb_part) {
621 if (sconf->bgmc && sconf->sb_part)
622 log2_sub_blocks = get_bits(gb, 2);
624 log2_sub_blocks = 2 * get_bits1(gb);
627 sub_blocks = 1 << log2_sub_blocks;
629 // do not continue in case of a damaged stream since
630 // block_length must be evenly divisible by sub_blocks
631 if (bd->block_length & (sub_blocks - 1)) {
632 av_log(avctx, AV_LOG_WARNING,
633 "Block length is not evenly divisible by the number of subblocks.\n");
637 sb_length = bd->block_length >> log2_sub_blocks;
640 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
641 for (k = 1; k < sub_blocks; k++)
642 s[k] = s[k - 1] + decode_rice(gb, 2);
644 for (k = 0; k < sub_blocks; k++) {
649 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
650 for (k = 1; k < sub_blocks; k++)
651 s[k] = s[k - 1] + decode_rice(gb, 0);
655 *bd->shift_lsbs = get_bits(gb, 4) + 1;
657 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
660 if (!sconf->rlslms) {
661 if (sconf->adapt_order) {
662 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
663 2, sconf->max_order + 1));
664 *bd->opt_order = get_bits(gb, opt_order_length);
666 *bd->opt_order = sconf->max_order;
669 opt_order = *bd->opt_order;
674 if (sconf->coef_table == 3) {
677 // read coefficient 0
678 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
680 // read coefficient 1
682 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
684 // read coefficients 2 to opt_order
685 for (k = 2; k < opt_order; k++)
686 quant_cof[k] = get_bits(gb, 7);
691 // read coefficient 0 to 19
692 k_max = FFMIN(opt_order, 20);
693 for (k = 0; k < k_max; k++) {
694 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
695 int offset = parcor_rice_table[sconf->coef_table][k][0];
696 quant_cof[k] = decode_rice(gb, rice_param) + offset;
699 // read coefficients 20 to 126
700 k_max = FFMIN(opt_order, 127);
701 for (; k < k_max; k++)
702 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
704 // read coefficients 127 to opt_order
705 for (; k < opt_order; k++)
706 quant_cof[k] = decode_rice(gb, 1);
708 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
711 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
714 for (k = 2; k < opt_order; k++)
715 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
719 // read LTP gain and lag values
720 if (sconf->long_term_prediction) {
721 *bd->use_ltp = get_bits1(gb);
726 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
727 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
729 r = get_unary(gb, 0, 4);
731 bd->ltp_gain[2] = ltp_gain_values[r][c];
733 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
734 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
736 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
737 *bd->ltp_lag += FFMAX(4, opt_order + 1);
741 // read first value and residuals in case of a random access block
744 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
746 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
748 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
750 start = FFMIN(opt_order, 3);
753 // read all residuals
757 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
758 unsigned int i = start;
760 // read most significant bits
765 ff_bgmc_decode_init(gb, &high, &low, &value);
767 current_res = bd->raw_samples + start;
769 for (sb = 0; sb < sub_blocks; sb++, i = 0) {
770 k [sb] = s[sb] > b ? s[sb] - b : 0;
771 delta[sb] = 5 - s[sb] + k[sb];
773 ff_bgmc_decode(gb, sb_length, current_res,
774 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
776 current_res += sb_length;
779 ff_bgmc_decode_end(gb);
782 // read least significant bits and tails
784 current_res = bd->raw_samples + start;
786 for (sb = 0; sb < sub_blocks; sb++, i = 0) {
787 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
788 unsigned int cur_k = k[sb];
789 unsigned int cur_s = s[sb];
791 for (; i < sb_length; i++) {
792 int32_t res = *current_res;
794 if (res == cur_tail_code) {
795 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
798 res = decode_rice(gb, cur_s);
801 res += (max_msb ) << cur_k;
803 res -= (max_msb - 1) << cur_k;
806 if (res > cur_tail_code)
816 res |= get_bits_long(gb, cur_k);
820 *current_res++ = res;
824 current_res = bd->raw_samples + start;
826 for (sb = 0; sb < sub_blocks; sb++, start = 0)
827 for (; start < sb_length; start++)
828 *current_res++ = decode_rice(gb, s[sb]);
831 if (!sconf->mc_coding || ctx->js_switch)
838 /** Decode the block data for a non-constant block
840 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
842 ALSSpecificConfig *sconf = &ctx->sconf;
843 unsigned int block_length = bd->block_length;
844 unsigned int smp = 0;
846 int opt_order = *bd->opt_order;
849 int32_t *quant_cof = bd->quant_cof;
850 int32_t *lpc_cof = bd->lpc_cof;
851 int32_t *raw_samples = bd->raw_samples;
852 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
853 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
855 // reverse long-term prediction
859 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
860 int center = ltp_smp - *bd->ltp_lag;
861 int begin = FFMAX(0, center - 2);
862 int end = center + 3;
863 int tab = 5 - (end - begin);
868 for (base = begin; base < end; base++, tab++)
869 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
871 raw_samples[ltp_smp] += y >> 7;
875 // reconstruct all samples from residuals
877 for (smp = 0; smp < opt_order; smp++) {
880 for (sb = 0; sb < smp; sb++)
881 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
883 *raw_samples++ -= y >> 20;
884 parcor_to_lpc(smp, quant_cof, lpc_cof);
887 for (k = 0; k < opt_order; k++)
888 parcor_to_lpc(k, quant_cof, lpc_cof);
890 // store previous samples in case that they have to be altered
891 if (*bd->store_prev_samples)
892 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
893 sizeof(*bd->prev_raw_samples) * sconf->max_order);
895 // reconstruct difference signal for prediction (joint-stereo)
896 if (bd->js_blocks && bd->raw_other) {
897 int32_t *left, *right;
899 if (bd->raw_other > raw_samples) { // D = R - L
901 right = bd->raw_other;
902 } else { // D = R - L
903 left = bd->raw_other;
907 for (sb = -1; sb >= -sconf->max_order; sb--)
908 raw_samples[sb] = right[sb] - left[sb];
911 // reconstruct shifted signal
913 for (sb = -1; sb >= -sconf->max_order; sb--)
914 raw_samples[sb] >>= *bd->shift_lsbs;
917 // reverse linear prediction coefficients for efficiency
918 lpc_cof = lpc_cof + opt_order;
920 for (sb = 0; sb < opt_order; sb++)
921 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
923 // reconstruct raw samples
924 raw_samples = bd->raw_samples + smp;
925 lpc_cof = lpc_cof_reversed + opt_order;
927 for (; raw_samples < raw_samples_end; raw_samples++) {
930 for (sb = -opt_order; sb < 0; sb++)
931 y += MUL64(lpc_cof[sb], raw_samples[sb]);
933 *raw_samples -= y >> 20;
936 raw_samples = bd->raw_samples;
938 // restore previous samples in case that they have been altered
939 if (*bd->store_prev_samples)
940 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
941 sizeof(*raw_samples) * sconf->max_order);
947 /** Read the block data.
949 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
951 GetBitContext *gb = &ctx->gb;
954 // read block type flag and read the samples accordingly
956 if (read_var_block_data(ctx, bd))
959 read_const_block_data(ctx, bd);
966 /** Decode the block data.
968 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
972 // read block type flag and read the samples accordingly
973 if (*bd->const_block)
974 decode_const_block_data(ctx, bd);
975 else if (decode_var_block_data(ctx, bd))
978 // TODO: read RLSLMS extension data
981 for (smp = 0; smp < bd->block_length; smp++)
982 bd->raw_samples[smp] <<= *bd->shift_lsbs;
988 /** Read and decode block data successively.
990 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
994 ret = read_block(ctx, bd);
999 ret = decode_block(ctx, bd);
1005 /** Compute the number of samples left to decode for the current frame and
1006 * sets these samples to zero.
1008 static void zero_remaining(unsigned int b, unsigned int b_max,
1009 const unsigned int *div_blocks, int32_t *buf)
1011 unsigned int count = 0;
1014 count += div_blocks[b];
1017 memset(buf, 0, sizeof(*buf) * count);
1021 /** Decode blocks independently.
1023 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1024 unsigned int c, const unsigned int *div_blocks,
1025 unsigned int *js_blocks)
1030 memset(&bd, 0, sizeof(ALSBlockData));
1032 bd.ra_block = ra_frame;
1033 bd.const_block = ctx->const_block;
1034 bd.shift_lsbs = ctx->shift_lsbs;
1035 bd.opt_order = ctx->opt_order;
1036 bd.store_prev_samples = ctx->store_prev_samples;
1037 bd.use_ltp = ctx->use_ltp;
1038 bd.ltp_lag = ctx->ltp_lag;
1039 bd.ltp_gain = ctx->ltp_gain[0];
1040 bd.quant_cof = ctx->quant_cof[0];
1041 bd.lpc_cof = ctx->lpc_cof[0];
1042 bd.prev_raw_samples = ctx->prev_raw_samples;
1043 bd.raw_samples = ctx->raw_samples[c];
1046 for (b = 0; b < ctx->num_blocks; b++) {
1047 bd.block_length = div_blocks[b];
1049 if (read_decode_block(ctx, &bd)) {
1050 // damaged block, write zero for the rest of the frame
1051 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1054 bd.raw_samples += div_blocks[b];
1062 /** Decode blocks dependently.
1064 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1065 unsigned int c, const unsigned int *div_blocks,
1066 unsigned int *js_blocks)
1068 ALSSpecificConfig *sconf = &ctx->sconf;
1069 unsigned int offset = 0;
1073 memset(bd, 0, 2 * sizeof(ALSBlockData));
1075 bd[0].ra_block = ra_frame;
1076 bd[0].const_block = ctx->const_block;
1077 bd[0].shift_lsbs = ctx->shift_lsbs;
1078 bd[0].opt_order = ctx->opt_order;
1079 bd[0].store_prev_samples = ctx->store_prev_samples;
1080 bd[0].use_ltp = ctx->use_ltp;
1081 bd[0].ltp_lag = ctx->ltp_lag;
1082 bd[0].ltp_gain = ctx->ltp_gain[0];
1083 bd[0].quant_cof = ctx->quant_cof[0];
1084 bd[0].lpc_cof = ctx->lpc_cof[0];
1085 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1086 bd[0].js_blocks = *js_blocks;
1088 bd[1].ra_block = ra_frame;
1089 bd[1].const_block = ctx->const_block;
1090 bd[1].shift_lsbs = ctx->shift_lsbs;
1091 bd[1].opt_order = ctx->opt_order;
1092 bd[1].store_prev_samples = ctx->store_prev_samples;
1093 bd[1].use_ltp = ctx->use_ltp;
1094 bd[1].ltp_lag = ctx->ltp_lag;
1095 bd[1].ltp_gain = ctx->ltp_gain[0];
1096 bd[1].quant_cof = ctx->quant_cof[0];
1097 bd[1].lpc_cof = ctx->lpc_cof[0];
1098 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1099 bd[1].js_blocks = *(js_blocks + 1);
1101 // decode all blocks
1102 for (b = 0; b < ctx->num_blocks; b++) {
1105 bd[0].block_length = div_blocks[b];
1106 bd[1].block_length = div_blocks[b];
1108 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1109 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1111 bd[0].raw_other = bd[1].raw_samples;
1112 bd[1].raw_other = bd[0].raw_samples;
1114 if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1115 // damaged block, write zero for the rest of the frame
1116 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1117 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1121 // reconstruct joint-stereo blocks
1122 if (bd[0].js_blocks) {
1123 if (bd[1].js_blocks)
1124 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1126 for (s = 0; s < div_blocks[b]; s++)
1127 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1128 } else if (bd[1].js_blocks) {
1129 for (s = 0; s < div_blocks[b]; s++)
1130 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1133 offset += div_blocks[b];
1138 // store carryover raw samples,
1139 // the others channel raw samples are stored by the calling function.
1140 memmove(ctx->raw_samples[c] - sconf->max_order,
1141 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1142 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1148 /** Read the channel data.
1150 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1152 GetBitContext *gb = &ctx->gb;
1153 ALSChannelData *current = cd;
1154 unsigned int channels = ctx->avctx->channels;
1157 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1158 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1160 if (current->master_channel >= channels) {
1161 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1165 if (current->master_channel != c) {
1166 current->time_diff_flag = get_bits1(gb);
1167 current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1168 current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
1169 current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1171 if (current->time_diff_flag) {
1172 current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1173 current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1174 current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1176 current->time_diff_sign = get_bits1(gb);
1177 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1185 if (entries == channels) {
1186 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1195 /** Recursively reverts the inter-channel correlation for a block.
1197 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1198 ALSChannelData **cd, int *reverted,
1199 unsigned int offset, int c)
1201 ALSChannelData *ch = cd[c];
1202 unsigned int dep = 0;
1203 unsigned int channels = ctx->avctx->channels;
1210 while (dep < channels && !ch[dep].stop_flag) {
1211 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1212 ch[dep].master_channel);
1217 if (dep == channels) {
1218 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1222 bd->const_block = ctx->const_block + c;
1223 bd->shift_lsbs = ctx->shift_lsbs + c;
1224 bd->opt_order = ctx->opt_order + c;
1225 bd->store_prev_samples = ctx->store_prev_samples + c;
1226 bd->use_ltp = ctx->use_ltp + c;
1227 bd->ltp_lag = ctx->ltp_lag + c;
1228 bd->ltp_gain = ctx->ltp_gain[c];
1229 bd->lpc_cof = ctx->lpc_cof[c];
1230 bd->quant_cof = ctx->quant_cof[c];
1231 bd->raw_samples = ctx->raw_samples[c] + offset;
1234 while (!ch[dep].stop_flag) {
1236 unsigned int begin = 1;
1237 unsigned int end = bd->block_length - 1;
1239 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1241 if (ch[dep].time_diff_flag) {
1242 int t = ch[dep].time_diff_index;
1244 if (ch[dep].time_diff_sign) {
1251 for (smp = begin; smp < end; smp++) {
1253 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1254 MUL64(ch[dep].weighting[1], master[smp ]) +
1255 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1256 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1257 MUL64(ch[dep].weighting[4], master[smp + t]) +
1258 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1260 bd->raw_samples[smp] += y >> 7;
1263 for (smp = begin; smp < end; smp++) {
1265 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1266 MUL64(ch[dep].weighting[1], master[smp ]) +
1267 MUL64(ch[dep].weighting[2], master[smp + 1]);
1269 bd->raw_samples[smp] += y >> 7;
1280 /** Read the frame data.
1282 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1284 ALSSpecificConfig *sconf = &ctx->sconf;
1285 AVCodecContext *avctx = ctx->avctx;
1286 GetBitContext *gb = &ctx->gb;
1287 unsigned int div_blocks[32]; ///< block sizes.
1289 unsigned int js_blocks[2];
1291 uint32_t bs_info = 0;
1293 // skip the size of the ra unit if present in the frame
1294 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1295 skip_bits_long(gb, 32);
1297 if (sconf->mc_coding && sconf->joint_stereo) {
1298 ctx->js_switch = get_bits1(gb);
1302 if (!sconf->mc_coding || ctx->js_switch) {
1303 int independent_bs = !sconf->joint_stereo;
1305 for (c = 0; c < avctx->channels; c++) {
1309 get_block_sizes(ctx, div_blocks, &bs_info);
1311 // if joint_stereo and block_switching is set, independent decoding
1312 // is signaled via the first bit of bs_info
1313 if (sconf->joint_stereo && sconf->block_switching)
1317 // if this is the last channel, it has to be decoded independently
1318 if (c == avctx->channels - 1)
1321 if (independent_bs) {
1322 if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1327 if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1333 // store carryover raw samples
1334 memmove(ctx->raw_samples[c] - sconf->max_order,
1335 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1336 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1338 } else { // multi-channel coding
1341 int *reverted_channels = ctx->reverted_channels;
1342 unsigned int offset = 0;
1344 for (c = 0; c < avctx->channels; c++)
1345 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1346 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1350 memset(&bd, 0, sizeof(ALSBlockData));
1351 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1353 bd.ra_block = ra_frame;
1354 bd.prev_raw_samples = ctx->prev_raw_samples;
1356 get_block_sizes(ctx, div_blocks, &bs_info);
1358 for (b = 0; b < ctx->num_blocks; b++) {
1359 bd.block_length = div_blocks[b];
1361 for (c = 0; c < avctx->channels; c++) {
1362 bd.const_block = ctx->const_block + c;
1363 bd.shift_lsbs = ctx->shift_lsbs + c;
1364 bd.opt_order = ctx->opt_order + c;
1365 bd.store_prev_samples = ctx->store_prev_samples + c;
1366 bd.use_ltp = ctx->use_ltp + c;
1367 bd.ltp_lag = ctx->ltp_lag + c;
1368 bd.ltp_gain = ctx->ltp_gain[c];
1369 bd.lpc_cof = ctx->lpc_cof[c];
1370 bd.quant_cof = ctx->quant_cof[c];
1371 bd.raw_samples = ctx->raw_samples[c] + offset;
1372 bd.raw_other = NULL;
1374 read_block(ctx, &bd);
1375 if (read_channel_data(ctx, ctx->chan_data[c], c))
1379 for (c = 0; c < avctx->channels; c++)
1380 if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1381 reverted_channels, offset, c))
1384 for (c = 0; c < avctx->channels; c++) {
1385 bd.const_block = ctx->const_block + c;
1386 bd.shift_lsbs = ctx->shift_lsbs + c;
1387 bd.opt_order = ctx->opt_order + c;
1388 bd.store_prev_samples = ctx->store_prev_samples + c;
1389 bd.use_ltp = ctx->use_ltp + c;
1390 bd.ltp_lag = ctx->ltp_lag + c;
1391 bd.ltp_gain = ctx->ltp_gain[c];
1392 bd.lpc_cof = ctx->lpc_cof[c];
1393 bd.quant_cof = ctx->quant_cof[c];
1394 bd.raw_samples = ctx->raw_samples[c] + offset;
1395 decode_block(ctx, &bd);
1398 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1399 offset += div_blocks[b];
1403 // store carryover raw samples
1404 for (c = 0; c < avctx->channels; c++)
1405 memmove(ctx->raw_samples[c] - sconf->max_order,
1406 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1407 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1410 // TODO: read_diff_float_data
1416 /** Decode an ALS frame.
1418 static int decode_frame(AVCodecContext *avctx,
1419 void *data, int *data_size,
1422 ALSDecContext *ctx = avctx->priv_data;
1423 ALSSpecificConfig *sconf = &ctx->sconf;
1424 const uint8_t *buffer = avpkt->data;
1425 int buffer_size = avpkt->size;
1426 int invalid_frame, size;
1427 unsigned int c, sample, ra_frame, bytes_read, shift;
1429 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1431 // In the case that the distance between random access frames is set to zero
1432 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1433 // For the first frame, if prediction is used, all samples used from the
1434 // previous frame are assumed to be zero.
1435 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1437 // the last frame to decode might have a different length
1438 if (sconf->samples != 0xFFFFFFFF)
1439 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1440 sconf->frame_length);
1442 ctx->cur_frame_length = sconf->frame_length;
1444 // decode the frame data
1445 if ((invalid_frame = read_frame_data(ctx, ra_frame) < 0))
1446 av_log(ctx->avctx, AV_LOG_WARNING,
1447 "Reading frame data failed. Skipping RA unit.\n");
1451 // check for size of decoded data
1452 size = ctx->cur_frame_length * avctx->channels *
1453 av_get_bytes_per_sample(avctx->sample_fmt);
1455 if (size > *data_size) {
1456 av_log(avctx, AV_LOG_ERROR, "Decoded data exceeds buffer size.\n");
1462 // transform decoded frame into output format
1463 #define INTERLEAVE_OUTPUT(bps) \
1465 int##bps##_t *dest = (int##bps##_t*) data; \
1466 shift = bps - ctx->avctx->bits_per_raw_sample; \
1467 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1468 for (c = 0; c < avctx->channels; c++) \
1469 *dest++ = ctx->raw_samples[c][sample] << shift; \
1472 if (ctx->avctx->bits_per_raw_sample <= 16) {
1473 INTERLEAVE_OUTPUT(16)
1475 INTERLEAVE_OUTPUT(32)
1479 if (sconf->crc_enabled && avctx->error_recognition >= FF_ER_CAREFUL) {
1480 int swap = HAVE_BIGENDIAN != sconf->msb_first;
1482 if (ctx->avctx->bits_per_raw_sample == 24) {
1483 int32_t *src = data;
1486 sample < ctx->cur_frame_length * avctx->channels;
1491 v = av_bswap32(src[sample]);
1494 if (!HAVE_BIGENDIAN)
1497 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1500 uint8_t *crc_source;
1503 if (ctx->avctx->bits_per_raw_sample <= 16) {
1504 int16_t *src = (int16_t*) data;
1505 int16_t *dest = (int16_t*) ctx->crc_buffer;
1507 sample < ctx->cur_frame_length * avctx->channels;
1509 *dest++ = av_bswap16(src[sample]);
1511 ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer, data,
1512 ctx->cur_frame_length * avctx->channels);
1514 crc_source = ctx->crc_buffer;
1519 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source, size);
1523 // check CRC sums if this is the last frame
1524 if (ctx->cur_frame_length != sconf->frame_length &&
1525 ctx->crc_org != ctx->crc) {
1526 av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1531 bytes_read = invalid_frame ? buffer_size :
1532 (get_bits_count(&ctx->gb) + 7) >> 3;
1538 /** Uninitialize the ALS decoder.
1540 static av_cold int decode_end(AVCodecContext *avctx)
1542 ALSDecContext *ctx = avctx->priv_data;
1544 av_freep(&ctx->sconf.chan_pos);
1546 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1548 av_freep(&ctx->const_block);
1549 av_freep(&ctx->shift_lsbs);
1550 av_freep(&ctx->opt_order);
1551 av_freep(&ctx->store_prev_samples);
1552 av_freep(&ctx->use_ltp);
1553 av_freep(&ctx->ltp_lag);
1554 av_freep(&ctx->ltp_gain);
1555 av_freep(&ctx->ltp_gain_buffer);
1556 av_freep(&ctx->quant_cof);
1557 av_freep(&ctx->lpc_cof);
1558 av_freep(&ctx->quant_cof_buffer);
1559 av_freep(&ctx->lpc_cof_buffer);
1560 av_freep(&ctx->lpc_cof_reversed_buffer);
1561 av_freep(&ctx->prev_raw_samples);
1562 av_freep(&ctx->raw_samples);
1563 av_freep(&ctx->raw_buffer);
1564 av_freep(&ctx->chan_data);
1565 av_freep(&ctx->chan_data_buffer);
1566 av_freep(&ctx->reverted_channels);
1567 av_freep(&ctx->crc_buffer);
1573 /** Initialize the ALS decoder.
1575 static av_cold int decode_init(AVCodecContext *avctx)
1578 unsigned int channel_size;
1580 ALSDecContext *ctx = avctx->priv_data;
1581 ALSSpecificConfig *sconf = &ctx->sconf;
1584 if (!avctx->extradata) {
1585 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1589 if (read_specific_config(ctx)) {
1590 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1595 if (check_specific_config(ctx)) {
1601 ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1603 if (sconf->floating) {
1604 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1605 avctx->bits_per_raw_sample = 32;
1607 avctx->sample_fmt = sconf->resolution > 1
1608 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1609 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1612 // set maximum Rice parameter for progressive decoding based on resolution
1613 // This is not specified in 14496-3 but actually done by the reference
1614 // codec RM22 revision 2.
1615 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1617 // set lag value for long-term prediction
1618 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1619 (avctx->sample_rate >= 192000);
1621 // allocate quantized parcor coefficient buffer
1622 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1624 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1625 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1626 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1627 num_buffers * sconf->max_order);
1628 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1629 num_buffers * sconf->max_order);
1630 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1633 if (!ctx->quant_cof || !ctx->lpc_cof ||
1634 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1635 !ctx->lpc_cof_reversed_buffer) {
1636 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1637 return AVERROR(ENOMEM);
1640 // assign quantized parcor coefficient buffers
1641 for (c = 0; c < num_buffers; c++) {
1642 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1643 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1646 // allocate and assign lag and gain data buffer for ltp mode
1647 ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1648 ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1649 ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1650 ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1651 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1652 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1653 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1654 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1657 if (!ctx->const_block || !ctx->shift_lsbs ||
1658 !ctx->opt_order || !ctx->store_prev_samples ||
1659 !ctx->use_ltp || !ctx->ltp_lag ||
1660 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1661 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1663 return AVERROR(ENOMEM);
1666 for (c = 0; c < num_buffers; c++)
1667 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1669 // allocate and assign channel data buffer for mcc mode
1670 if (sconf->mc_coding) {
1671 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1672 num_buffers * num_buffers);
1673 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1675 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1678 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1679 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1681 return AVERROR(ENOMEM);
1684 for (c = 0; c < num_buffers; c++)
1685 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1687 ctx->chan_data = NULL;
1688 ctx->chan_data_buffer = NULL;
1689 ctx->reverted_channels = NULL;
1692 avctx->frame_size = sconf->frame_length;
1693 channel_size = sconf->frame_length + sconf->max_order;
1695 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1696 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1697 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1699 // allocate previous raw sample buffer
1700 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1701 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1703 return AVERROR(ENOMEM);
1706 // assign raw samples buffers
1707 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1708 for (c = 1; c < avctx->channels; c++)
1709 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1711 // allocate crc buffer
1712 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1713 avctx->error_recognition >= FF_ER_CAREFUL) {
1714 ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1715 ctx->cur_frame_length *
1717 av_get_bytes_per_sample(avctx->sample_fmt));
1718 if (!ctx->crc_buffer) {
1719 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1721 return AVERROR(ENOMEM);
1725 dsputil_init(&ctx->dsp, avctx);
1731 /** Flush (reset) the frame ID after seeking.
1733 static av_cold void flush(AVCodecContext *avctx)
1735 ALSDecContext *ctx = avctx->priv_data;
1741 AVCodec ff_als_decoder = {
1743 .type = AVMEDIA_TYPE_AUDIO,
1744 .id = CODEC_ID_MP4ALS,
1745 .priv_data_size = sizeof(ALSDecContext),
1746 .init = decode_init,
1747 .close = decode_end,
1748 .decode = decode_frame,
1750 .capabilities = CODEC_CAP_SUBFRAMES,
1751 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),