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
23 * @file libavcodec/alsdec.c
25 * @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
35 #include "mpeg4audio.h"
36 #include "bytestream.h"
41 /** Rice parameters and corresponding index offsets for decoding the
42 * indices of scaled PARCOR values. The table choosen 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 frame_length; ///< frame length for each frame (last frame may differ)
158 int ra_distance; ///< distance between RA frames (in frames, 0...255)
159 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
160 int adapt_order; ///< adaptive order: 1 = on, 0 = off
161 int coef_table; ///< table index of Rice code parameters
162 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
163 int max_order; ///< maximum prediction order (0..1023)
164 int block_switching; ///< number of block switching levels
165 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
166 int sb_part; ///< sub-block partition
167 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
168 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
169 int chan_config; ///< indicates that a chan_config_info field is present
170 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
171 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
172 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
173 int *chan_pos; ///< original channel positions
188 AVCodecContext *avctx;
189 ALSSpecificConfig sconf;
191 unsigned int cur_frame_length; ///< length of the current frame to decode
192 unsigned int frame_id; ///< the frame ID / number of the current frame
193 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
194 unsigned int num_blocks; ///< number of blocks used in the current frame
195 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
196 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
197 unsigned int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
198 int ltp_lag_length; ///< number of bits used for ltp lag value
199 int *use_ltp; ///< contains use_ltp flags for all channels
200 int *ltp_lag; ///< contains ltp lag values for all channels
201 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
202 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
203 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
204 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
205 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
206 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
207 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
208 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
209 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
210 int *reverted_channels; ///< stores a flag for each reverted channel
211 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
212 int32_t **raw_samples; ///< decoded raw samples for each channel
213 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
218 unsigned int block_length; ///< number of samples within the block
219 unsigned int ra_block; ///< if true, this is a random access block
220 int const_block; ///< if true, this is a constant value block
221 int32_t const_val; ///< the sample value of a constant block
222 int js_blocks; ///< true if this block contains a difference signal
223 unsigned int shift_lsbs; ///< shift of values for this block
224 unsigned int opt_order; ///< prediction order of this block
225 int store_prev_samples;///< if true, carryover samples have to be stored
226 int *use_ltp; ///< if true, long-term prediction is used
227 int *ltp_lag; ///< lag value for long-term prediction
228 int *ltp_gain; ///< gain values for ltp 5-tap filter
229 int32_t *quant_cof; ///< quantized parcor coefficients
230 int32_t *lpc_cof; ///< coefficients of the direct form prediction
231 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
232 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
233 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
237 static av_cold void dprint_specific_config(ALSDecContext *ctx)
240 AVCodecContext *avctx = ctx->avctx;
241 ALSSpecificConfig *sconf = &ctx->sconf;
243 dprintf(avctx, "resolution = %i\n", sconf->resolution);
244 dprintf(avctx, "floating = %i\n", sconf->floating);
245 dprintf(avctx, "frame_length = %i\n", sconf->frame_length);
246 dprintf(avctx, "ra_distance = %i\n", sconf->ra_distance);
247 dprintf(avctx, "ra_flag = %i\n", sconf->ra_flag);
248 dprintf(avctx, "adapt_order = %i\n", sconf->adapt_order);
249 dprintf(avctx, "coef_table = %i\n", sconf->coef_table);
250 dprintf(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
251 dprintf(avctx, "max_order = %i\n", sconf->max_order);
252 dprintf(avctx, "block_switching = %i\n", sconf->block_switching);
253 dprintf(avctx, "bgmc = %i\n", sconf->bgmc);
254 dprintf(avctx, "sb_part = %i\n", sconf->sb_part);
255 dprintf(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
256 dprintf(avctx, "mc_coding = %i\n", sconf->mc_coding);
257 dprintf(avctx, "chan_config = %i\n", sconf->chan_config);
258 dprintf(avctx, "chan_sort = %i\n", sconf->chan_sort);
259 dprintf(avctx, "RLSLMS = %i\n", sconf->rlslms);
260 dprintf(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
265 /** Reads an ALSSpecificConfig from a buffer into the output struct.
267 static av_cold int read_specific_config(ALSDecContext *ctx)
271 int i, config_offset, crc_enabled;
272 MPEG4AudioConfig m4ac;
273 ALSSpecificConfig *sconf = &ctx->sconf;
274 AVCodecContext *avctx = ctx->avctx;
275 uint32_t als_id, header_size, trailer_size;
277 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
279 config_offset = ff_mpeg4audio_get_config(&m4ac, avctx->extradata,
280 avctx->extradata_size);
282 if (config_offset < 0)
285 skip_bits_long(&gb, config_offset);
287 if (get_bits_left(&gb) < (30 << 3))
290 // read the fixed items
291 als_id = get_bits_long(&gb, 32);
292 avctx->sample_rate = m4ac.sample_rate;
293 skip_bits_long(&gb, 32); // sample rate already known
294 sconf->samples = get_bits_long(&gb, 32);
295 avctx->channels = m4ac.channels;
296 skip_bits(&gb, 16); // number of channels already knwon
297 skip_bits(&gb, 3); // skip file_type
298 sconf->resolution = get_bits(&gb, 3);
299 sconf->floating = get_bits1(&gb);
300 skip_bits1(&gb); // skip msb_first
301 sconf->frame_length = get_bits(&gb, 16) + 1;
302 sconf->ra_distance = get_bits(&gb, 8);
303 sconf->ra_flag = get_bits(&gb, 2);
304 sconf->adapt_order = get_bits1(&gb);
305 sconf->coef_table = get_bits(&gb, 2);
306 sconf->long_term_prediction = get_bits1(&gb);
307 sconf->max_order = get_bits(&gb, 10);
308 sconf->block_switching = get_bits(&gb, 2);
309 sconf->bgmc = get_bits1(&gb);
310 sconf->sb_part = get_bits1(&gb);
311 sconf->joint_stereo = get_bits1(&gb);
312 sconf->mc_coding = get_bits1(&gb);
313 sconf->chan_config = get_bits1(&gb);
314 sconf->chan_sort = get_bits1(&gb);
315 crc_enabled = get_bits1(&gb);
316 sconf->rlslms = get_bits1(&gb);
317 skip_bits(&gb, 5); // skip 5 reserved bits
318 skip_bits1(&gb); // skip aux_data_enabled
321 // check for ALSSpecificConfig struct
322 if (als_id != MKBETAG('A','L','S','\0'))
325 ctx->cur_frame_length = sconf->frame_length;
327 // read channel config
328 if (sconf->chan_config)
329 sconf->chan_config_info = get_bits(&gb, 16);
330 // TODO: use this to set avctx->channel_layout
333 // read channel sorting
334 if (sconf->chan_sort && avctx->channels > 1) {
335 int chan_pos_bits = av_ceil_log2(avctx->channels);
336 int bits_needed = avctx->channels * chan_pos_bits + 7;
337 if (get_bits_left(&gb) < bits_needed)
340 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
341 return AVERROR(ENOMEM);
343 for (i = 0; i < avctx->channels; i++)
344 sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
347 // TODO: use this to actually do channel sorting
349 sconf->chan_sort = 0;
353 // read fixed header and trailer sizes,
354 // if size = 0xFFFFFFFF then there is no data field!
355 if (get_bits_left(&gb) < 64)
358 header_size = get_bits_long(&gb, 32);
359 trailer_size = get_bits_long(&gb, 32);
360 if (header_size == 0xFFFFFFFF)
362 if (trailer_size == 0xFFFFFFFF)
365 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
368 // skip the header and trailer data
369 if (get_bits_left(&gb) < ht_size)
372 if (ht_size > INT32_MAX)
375 skip_bits_long(&gb, ht_size);
380 if (get_bits_left(&gb) < 32)
383 skip_bits_long(&gb, 32);
387 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
389 dprint_specific_config(ctx);
395 /** Checks the ALSSpecificConfig for unsupported features.
397 static int check_specific_config(ALSDecContext *ctx)
399 ALSSpecificConfig *sconf = &ctx->sconf;
402 // report unsupported feature and set error value
403 #define MISSING_ERR(cond, str, errval) \
406 av_log_missing_feature(ctx->avctx, str, 0); \
411 MISSING_ERR(sconf->floating, "Floating point decoding", -1);
412 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
413 MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
419 /** Parses the bs_info field to extract the block partitioning used in
420 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
422 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
423 unsigned int div, unsigned int **div_blocks,
424 unsigned int *num_blocks)
426 if (n < 31 && ((bs_info << n) & 0x40000000)) {
427 // if the level is valid and the investigated bit n is set
428 // then recursively check both children at bits (2n+1) and (2n+2)
431 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
432 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
434 // else the bit is not set or the last level has been reached
435 // (bit implicitly not set)
443 /** Reads and decodes a Rice codeword.
445 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
447 int max = get_bits_left(gb) - k;
448 int q = get_unary(gb, 0, max);
449 int r = k ? get_bits1(gb) : !(q & 1);
453 q += get_bits_long(gb, k - 1);
461 /** Converts PARCOR coefficient k to direct filter coefficient.
463 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
467 for (i = 0, j = k - 1; i < j; i++, j--) {
468 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
469 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
473 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
479 /** Reads block switching field if necessary and sets actual block sizes.
480 * Also assures that the block sizes of the last frame correspond to the
481 * actual number of samples.
483 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
486 ALSSpecificConfig *sconf = &ctx->sconf;
487 GetBitContext *gb = &ctx->gb;
488 unsigned int *ptr_div_blocks = div_blocks;
491 if (sconf->block_switching) {
492 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
493 *bs_info = get_bits_long(gb, bs_info_len);
494 *bs_info <<= (32 - bs_info_len);
498 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
500 // The last frame may have an overdetermined block structure given in
501 // the bitstream. In that case the defined block structure would need
502 // more samples than available to be consistent.
503 // The block structure is actually used but the block sizes are adapted
504 // to fit the actual number of available samples.
505 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
506 // This results in the actual block sizes: 2 2 1 0.
507 // This is not specified in 14496-3 but actually done by the reference
508 // codec RM22 revision 2.
509 // This appears to happen in case of an odd number of samples in the last
510 // frame which is actually not allowed by the block length switching part
512 // The ALS conformance files feature an odd number of samples in the last
515 for (b = 0; b < ctx->num_blocks; b++)
516 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
518 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
519 unsigned int remaining = ctx->cur_frame_length;
521 for (b = 0; b < ctx->num_blocks; b++) {
522 if (remaining <= div_blocks[b]) {
523 div_blocks[b] = remaining;
524 ctx->num_blocks = b + 1;
528 remaining -= div_blocks[b];
534 /** Reads the block data for a constant block
536 static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
538 ALSSpecificConfig *sconf = &ctx->sconf;
539 AVCodecContext *avctx = ctx->avctx;
540 GetBitContext *gb = &ctx->gb;
543 bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
544 bd->js_blocks = get_bits1(gb);
546 // skip 5 reserved bits
549 if (bd->const_block) {
550 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
551 bd->const_val = get_sbits_long(gb, const_val_bits);
554 // ensure constant block decoding by reusing this field
559 /** Decodes the block data for a constant block
561 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
563 int smp = bd->block_length;
564 int32_t val = bd->const_val;
565 int32_t *dst = bd->raw_samples;
567 // write raw samples into buffer
573 /** Reads the block data for a non-constant block
575 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
577 ALSSpecificConfig *sconf = &ctx->sconf;
578 AVCodecContext *avctx = ctx->avctx;
579 GetBitContext *gb = &ctx->gb;
583 unsigned int sub_blocks, log2_sub_blocks, sb_length;
584 unsigned int start = 0;
585 unsigned int opt_order;
587 int32_t *quant_cof = bd->quant_cof;
588 int32_t *current_res;
591 // ensure variable block decoding by reusing this field
595 bd->js_blocks = get_bits1(gb);
597 opt_order = bd->opt_order;
599 // determine the number of subblocks for entropy decoding
600 if (!sconf->bgmc && !sconf->sb_part) {
603 if (sconf->bgmc && sconf->sb_part)
604 log2_sub_blocks = get_bits(gb, 2);
606 log2_sub_blocks = 2 * get_bits1(gb);
609 sub_blocks = 1 << log2_sub_blocks;
611 // do not continue in case of a damaged stream since
612 // block_length must be evenly divisible by sub_blocks
613 if (bd->block_length & (sub_blocks - 1)) {
614 av_log(avctx, AV_LOG_WARNING,
615 "Block length is not evenly divisible by the number of subblocks.\n");
619 sb_length = bd->block_length >> log2_sub_blocks;
622 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
623 for (k = 1; k < sub_blocks; k++)
624 s[k] = s[k - 1] + decode_rice(gb, 2);
626 for (k = 0; k < sub_blocks; k++) {
631 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
632 for (k = 1; k < sub_blocks; k++)
633 s[k] = s[k - 1] + decode_rice(gb, 0);
637 bd->shift_lsbs = get_bits(gb, 4) + 1;
639 bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || bd->shift_lsbs;
642 if (!sconf->rlslms) {
643 if (sconf->adapt_order) {
644 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
645 2, sconf->max_order + 1));
646 bd->opt_order = get_bits(gb, opt_order_length);
648 bd->opt_order = sconf->max_order;
651 opt_order = bd->opt_order;
656 if (sconf->coef_table == 3) {
659 // read coefficient 0
660 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
662 // read coefficient 1
664 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
666 // read coefficients 2 to opt_order
667 for (k = 2; k < opt_order; k++)
668 quant_cof[k] = get_bits(gb, 7);
673 // read coefficient 0 to 19
674 k_max = FFMIN(opt_order, 20);
675 for (k = 0; k < k_max; k++) {
676 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
677 int offset = parcor_rice_table[sconf->coef_table][k][0];
678 quant_cof[k] = decode_rice(gb, rice_param) + offset;
681 // read coefficients 20 to 126
682 k_max = FFMIN(opt_order, 127);
683 for (; k < k_max; k++)
684 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
686 // read coefficients 127 to opt_order
687 for (; k < opt_order; k++)
688 quant_cof[k] = decode_rice(gb, 1);
690 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
693 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
696 for (k = 2; k < opt_order; k++)
697 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
701 // read LTP gain and lag values
702 if (sconf->long_term_prediction) {
703 *bd->use_ltp = get_bits1(gb);
708 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
709 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
711 r = get_unary(gb, 0, 4);
713 bd->ltp_gain[2] = ltp_gain_values[r][c];
715 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
716 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
718 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
719 *bd->ltp_lag += FFMAX(4, opt_order + 1);
723 // read first value and residuals in case of a random access block
726 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
728 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
730 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
732 start = FFMIN(opt_order, 3);
735 // read all residuals
737 unsigned int delta[sub_blocks];
738 unsigned int k [sub_blocks];
739 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
740 unsigned int i = start;
742 // read most significant bits
747 ff_bgmc_decode_init(gb, &high, &low, &value);
749 current_res = bd->raw_samples + start;
751 for (sb = 0; sb < sub_blocks; sb++, i = 0) {
752 k [sb] = s[sb] > b ? s[sb] - b : 0;
753 delta[sb] = 5 - s[sb] + k[sb];
755 ff_bgmc_decode(gb, sb_length, current_res,
756 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
758 current_res += sb_length;
761 ff_bgmc_decode_end(gb);
764 // read least significant bits and tails
766 current_res = bd->raw_samples + start;
768 for (sb = 0; sb < sub_blocks; sb++, i = 0) {
769 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
770 unsigned int cur_k = k[sb];
771 unsigned int cur_s = s[sb];
773 for (; i < sb_length; i++) {
774 int32_t res = *current_res;
776 if (res == cur_tail_code) {
777 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
780 res = decode_rice(gb, cur_s);
783 res += (max_msb ) << cur_k;
785 res -= (max_msb - 1) << cur_k;
788 if (res > cur_tail_code)
798 res |= get_bits_long(gb, cur_k);
802 *current_res++ = res;
806 current_res = bd->raw_samples + start;
808 for (sb = 0; sb < sub_blocks; sb++, start = 0)
809 for (; start < sb_length; start++)
810 *current_res++ = decode_rice(gb, s[sb]);
813 if (!sconf->mc_coding || ctx->js_switch)
820 /** Decodes the block data for a non-constant block
822 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
824 ALSSpecificConfig *sconf = &ctx->sconf;
825 unsigned int block_length = bd->block_length;
826 unsigned int smp = 0;
828 int opt_order = bd->opt_order;
831 int32_t *quant_cof = bd->quant_cof;
832 int32_t *lpc_cof = bd->lpc_cof;
833 int32_t *raw_samples = bd->raw_samples;
834 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
835 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
837 // reverse long-term prediction
841 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
842 int center = ltp_smp - *bd->ltp_lag;
843 int begin = FFMAX(0, center - 2);
844 int end = center + 3;
845 int tab = 5 - (end - begin);
850 for (base = begin; base < end; base++, tab++)
851 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
853 raw_samples[ltp_smp] += y >> 7;
857 // reconstruct all samples from residuals
859 for (smp = 0; smp < opt_order; smp++) {
862 for (sb = 0; sb < smp; sb++)
863 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
865 *raw_samples++ -= y >> 20;
866 parcor_to_lpc(smp, quant_cof, lpc_cof);
869 for (k = 0; k < opt_order; k++)
870 parcor_to_lpc(k, quant_cof, lpc_cof);
872 // store previous samples in case that they have to be altered
873 if (bd->store_prev_samples)
874 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
875 sizeof(*bd->prev_raw_samples) * sconf->max_order);
877 // reconstruct difference signal for prediction (joint-stereo)
878 if (bd->js_blocks && bd->raw_other) {
879 int32_t *left, *right;
881 if (bd->raw_other > raw_samples) { // D = R - L
883 right = bd->raw_other;
884 } else { // D = R - L
885 left = bd->raw_other;
889 for (sb = -1; sb >= -sconf->max_order; sb--)
890 raw_samples[sb] = right[sb] - left[sb];
893 // reconstruct shifted signal
895 for (sb = -1; sb >= -sconf->max_order; sb--)
896 raw_samples[sb] >>= bd->shift_lsbs;
899 // reverse linear prediction coefficients for efficiency
900 lpc_cof = lpc_cof + opt_order;
902 for (sb = 0; sb < opt_order; sb++)
903 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
905 // reconstruct raw samples
906 raw_samples = bd->raw_samples + smp;
907 lpc_cof = lpc_cof_reversed + opt_order;
909 for (; raw_samples < raw_samples_end; raw_samples++) {
912 for (sb = -opt_order; sb < 0; sb++)
913 y += MUL64(lpc_cof[sb], raw_samples[sb]);
915 *raw_samples -= y >> 20;
918 raw_samples = bd->raw_samples;
920 // restore previous samples in case that they have been altered
921 if (bd->store_prev_samples)
922 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
923 sizeof(*raw_samples) * sconf->max_order);
929 /** Reads the block data.
931 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
933 GetBitContext *gb = &ctx->gb;
935 // read block type flag and read the samples accordingly
937 if (read_var_block_data(ctx, bd))
940 read_const_block_data(ctx, bd);
947 /** Decodes the block data.
949 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
953 // read block type flag and read the samples accordingly
955 decode_const_block_data(ctx, bd);
956 else if (decode_var_block_data(ctx, bd))
959 // TODO: read RLSLMS extension data
962 for (smp = 0; smp < bd->block_length; smp++)
963 bd->raw_samples[smp] <<= bd->shift_lsbs;
969 /** Reads and decodes block data successively.
971 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
975 ret = read_block(ctx, bd);
980 ret = decode_block(ctx, bd);
986 /** Computes the number of samples left to decode for the current frame and
987 * sets these samples to zero.
989 static void zero_remaining(unsigned int b, unsigned int b_max,
990 const unsigned int *div_blocks, int32_t *buf)
992 unsigned int count = 0;
995 count += div_blocks[b];
998 memset(buf, 0, sizeof(*buf) * count);
1002 /** Decodes blocks independently.
1004 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1005 unsigned int c, const unsigned int *div_blocks,
1006 unsigned int *js_blocks)
1011 memset(&bd, 0, sizeof(ALSBlockData));
1013 bd.ra_block = ra_frame;
1014 bd.use_ltp = ctx->use_ltp;
1015 bd.ltp_lag = ctx->ltp_lag;
1016 bd.ltp_gain = ctx->ltp_gain[0];
1017 bd.quant_cof = ctx->quant_cof[0];
1018 bd.lpc_cof = ctx->lpc_cof[0];
1019 bd.prev_raw_samples = ctx->prev_raw_samples;
1020 bd.raw_samples = ctx->raw_samples[c];
1023 for (b = 0; b < ctx->num_blocks; b++) {
1025 bd.block_length = div_blocks[b];
1027 if (read_decode_block(ctx, &bd)) {
1028 // damaged block, write zero for the rest of the frame
1029 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1032 bd.raw_samples += div_blocks[b];
1040 /** Decodes blocks dependently.
1042 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1043 unsigned int c, const unsigned int *div_blocks,
1044 unsigned int *js_blocks)
1046 ALSSpecificConfig *sconf = &ctx->sconf;
1047 unsigned int offset = 0;
1051 memset(bd, 0, 2 * sizeof(ALSBlockData));
1053 bd[0].ra_block = ra_frame;
1054 bd[0].use_ltp = ctx->use_ltp;
1055 bd[0].ltp_lag = ctx->ltp_lag;
1056 bd[0].ltp_gain = ctx->ltp_gain[0];
1057 bd[0].quant_cof = ctx->quant_cof[0];
1058 bd[0].lpc_cof = ctx->lpc_cof[0];
1059 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1060 bd[0].js_blocks = *js_blocks;
1062 bd[1].ra_block = ra_frame;
1063 bd[1].use_ltp = ctx->use_ltp;
1064 bd[1].ltp_lag = ctx->ltp_lag;
1065 bd[1].ltp_gain = ctx->ltp_gain[0];
1066 bd[1].quant_cof = ctx->quant_cof[0];
1067 bd[1].lpc_cof = ctx->lpc_cof[0];
1068 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1069 bd[1].js_blocks = *(js_blocks + 1);
1071 // decode all blocks
1072 for (b = 0; b < ctx->num_blocks; b++) {
1075 bd[0].shift_lsbs = 0;
1076 bd[1].shift_lsbs = 0;
1078 bd[0].block_length = div_blocks[b];
1079 bd[1].block_length = div_blocks[b];
1081 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1082 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1084 bd[0].raw_other = bd[1].raw_samples;
1085 bd[1].raw_other = bd[0].raw_samples;
1087 if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1088 // damaged block, write zero for the rest of the frame
1089 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1090 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1094 // reconstruct joint-stereo blocks
1095 if (bd[0].js_blocks) {
1096 if (bd[1].js_blocks)
1097 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1099 for (s = 0; s < div_blocks[b]; s++)
1100 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1101 } else if (bd[1].js_blocks) {
1102 for (s = 0; s < div_blocks[b]; s++)
1103 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1106 offset += div_blocks[b];
1111 // store carryover raw samples,
1112 // the others channel raw samples are stored by the calling function.
1113 memmove(ctx->raw_samples[c] - sconf->max_order,
1114 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1115 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1121 /** Reads the channel data.
1123 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1125 GetBitContext *gb = &ctx->gb;
1126 ALSChannelData *current = cd;
1127 unsigned int channels = ctx->avctx->channels;
1130 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1131 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1133 if (current->master_channel >= channels) {
1134 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1138 if (current->master_channel != c) {
1139 current->time_diff_flag = get_bits1(gb);
1140 current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1141 current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
1142 current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1144 if (current->time_diff_flag) {
1145 current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1146 current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1147 current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1149 current->time_diff_sign = get_bits1(gb);
1150 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1158 if (entries == channels) {
1159 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1168 /** Recursively reverts the inter-channel correlation for a block.
1170 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1171 ALSChannelData **cd, int *reverted,
1172 unsigned int offset, int c)
1174 ALSChannelData *ch = cd[c];
1175 unsigned int dep = 0;
1176 unsigned int channels = ctx->avctx->channels;
1183 while (dep < channels && !ch[dep].stop_flag) {
1184 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1185 ch[dep].master_channel);
1190 if (dep == channels) {
1191 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1195 bd->use_ltp = ctx->use_ltp + c;
1196 bd->ltp_lag = ctx->ltp_lag + c;
1197 bd->ltp_gain = ctx->ltp_gain[c];
1198 bd->lpc_cof = ctx->lpc_cof[c];
1199 bd->quant_cof = ctx->quant_cof[c];
1200 bd->raw_samples = ctx->raw_samples[c] + offset;
1203 while (!ch[dep].stop_flag) {
1205 unsigned int begin = 1;
1206 unsigned int end = bd->block_length - 1;
1208 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1210 if (ch[dep].time_diff_flag) {
1211 int t = ch[dep].time_diff_index;
1213 if (ch[dep].time_diff_sign) {
1220 for (smp = begin; smp < end; smp++) {
1222 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1223 MUL64(ch[dep].weighting[1], master[smp ]) +
1224 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1225 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1226 MUL64(ch[dep].weighting[4], master[smp + t]) +
1227 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1229 bd->raw_samples[smp] += y >> 7;
1232 for (smp = begin; smp < end; smp++) {
1234 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1235 MUL64(ch[dep].weighting[1], master[smp ]) +
1236 MUL64(ch[dep].weighting[2], master[smp + 1]);
1238 bd->raw_samples[smp] += y >> 7;
1249 /** Reads the frame data.
1251 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1253 ALSSpecificConfig *sconf = &ctx->sconf;
1254 AVCodecContext *avctx = ctx->avctx;
1255 GetBitContext *gb = &ctx->gb;
1256 unsigned int div_blocks[32]; ///< block sizes.
1258 unsigned int js_blocks[2];
1260 uint32_t bs_info = 0;
1262 // skip the size of the ra unit if present in the frame
1263 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1264 skip_bits_long(gb, 32);
1266 if (sconf->mc_coding && sconf->joint_stereo) {
1267 ctx->js_switch = get_bits1(gb);
1271 if (!sconf->mc_coding || ctx->js_switch) {
1272 int independent_bs = !sconf->joint_stereo;
1274 for (c = 0; c < avctx->channels; c++) {
1278 get_block_sizes(ctx, div_blocks, &bs_info);
1280 // if joint_stereo and block_switching is set, independent decoding
1281 // is signaled via the first bit of bs_info
1282 if (sconf->joint_stereo && sconf->block_switching)
1286 // if this is the last channel, it has to be decoded independently
1287 if (c == avctx->channels - 1)
1290 if (independent_bs) {
1291 if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1296 if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1302 // store carryover raw samples
1303 memmove(ctx->raw_samples[c] - sconf->max_order,
1304 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1305 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1307 } else { // multi-channel coding
1310 int *reverted_channels = ctx->reverted_channels;
1311 unsigned int offset = 0;
1313 for (c = 0; c < avctx->channels; c++)
1314 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1315 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1319 memset(&bd, 0, sizeof(ALSBlockData));
1320 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1322 bd.ra_block = ra_frame;
1323 bd.prev_raw_samples = ctx->prev_raw_samples;
1325 get_block_sizes(ctx, div_blocks, &bs_info);
1327 for (b = 0; b < ctx->num_blocks; b++) {
1329 bd.block_length = div_blocks[b];
1331 for (c = 0; c < avctx->channels; c++) {
1332 bd.use_ltp = ctx->use_ltp + c;
1333 bd.ltp_lag = ctx->ltp_lag + c;
1334 bd.ltp_gain = ctx->ltp_gain[c];
1335 bd.lpc_cof = ctx->lpc_cof[c];
1336 bd.quant_cof = ctx->quant_cof[c];
1337 bd.raw_samples = ctx->raw_samples[c] + offset;
1338 bd.raw_other = NULL;
1340 read_block(ctx, &bd);
1341 if (read_channel_data(ctx, ctx->chan_data[c], c))
1345 for (c = 0; c < avctx->channels; c++)
1346 if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1347 reverted_channels, offset, c))
1350 for (c = 0; c < avctx->channels; c++) {
1351 bd.use_ltp = ctx->use_ltp + c;
1352 bd.ltp_lag = ctx->ltp_lag + c;
1353 bd.ltp_gain = ctx->ltp_gain[c];
1354 bd.lpc_cof = ctx->lpc_cof[c];
1355 bd.quant_cof = ctx->quant_cof[c];
1356 bd.raw_samples = ctx->raw_samples[c] + offset;
1357 decode_block(ctx, &bd);
1360 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1361 offset += div_blocks[b];
1365 // store carryover raw samples
1366 for (c = 0; c < avctx->channels; c++)
1367 memmove(ctx->raw_samples[c] - sconf->max_order,
1368 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1369 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1372 // TODO: read_diff_float_data
1378 /** Decodes an ALS frame.
1380 static int decode_frame(AVCodecContext *avctx,
1381 void *data, int *data_size,
1384 ALSDecContext *ctx = avctx->priv_data;
1385 ALSSpecificConfig *sconf = &ctx->sconf;
1386 const uint8_t *buffer = avpkt->data;
1387 int buffer_size = avpkt->size;
1388 int invalid_frame, size;
1389 unsigned int c, sample, ra_frame, bytes_read, shift;
1391 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1393 // In the case that the distance between random access frames is set to zero
1394 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1395 // For the first frame, if prediction is used, all samples used from the
1396 // previous frame are assumed to be zero.
1397 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1399 // the last frame to decode might have a different length
1400 if (sconf->samples != 0xFFFFFFFF)
1401 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1402 sconf->frame_length);
1404 ctx->cur_frame_length = sconf->frame_length;
1406 // decode the frame data
1407 if ((invalid_frame = read_frame_data(ctx, ra_frame) < 0))
1408 av_log(ctx->avctx, AV_LOG_WARNING,
1409 "Reading frame data failed. Skipping RA unit.\n");
1413 // check for size of decoded data
1414 size = ctx->cur_frame_length * avctx->channels *
1415 (av_get_bits_per_sample_format(avctx->sample_fmt) >> 3);
1417 if (size > *data_size) {
1418 av_log(avctx, AV_LOG_ERROR, "Decoded data exceeds buffer size.\n");
1424 // transform decoded frame into output format
1425 #define INTERLEAVE_OUTPUT(bps) \
1427 int##bps##_t *dest = (int##bps##_t*) data; \
1428 shift = bps - ctx->avctx->bits_per_raw_sample; \
1429 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1430 for (c = 0; c < avctx->channels; c++) \
1431 *dest++ = ctx->raw_samples[c][sample] << shift; \
1434 if (ctx->avctx->bits_per_raw_sample <= 16) {
1435 INTERLEAVE_OUTPUT(16)
1437 INTERLEAVE_OUTPUT(32)
1440 bytes_read = invalid_frame ? buffer_size :
1441 (get_bits_count(&ctx->gb) + 7) >> 3;
1447 /** Uninitializes the ALS decoder.
1449 static av_cold int decode_end(AVCodecContext *avctx)
1451 ALSDecContext *ctx = avctx->priv_data;
1453 av_freep(&ctx->sconf.chan_pos);
1455 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1457 av_freep(&ctx->use_ltp);
1458 av_freep(&ctx->ltp_lag);
1459 av_freep(&ctx->ltp_gain);
1460 av_freep(&ctx->ltp_gain_buffer);
1461 av_freep(&ctx->quant_cof);
1462 av_freep(&ctx->lpc_cof);
1463 av_freep(&ctx->quant_cof_buffer);
1464 av_freep(&ctx->lpc_cof_buffer);
1465 av_freep(&ctx->lpc_cof_reversed_buffer);
1466 av_freep(&ctx->prev_raw_samples);
1467 av_freep(&ctx->raw_samples);
1468 av_freep(&ctx->raw_buffer);
1469 av_freep(&ctx->chan_data);
1470 av_freep(&ctx->chan_data_buffer);
1471 av_freep(&ctx->reverted_channels);
1477 /** Initializes the ALS decoder.
1479 static av_cold int decode_init(AVCodecContext *avctx)
1482 unsigned int channel_size;
1484 ALSDecContext *ctx = avctx->priv_data;
1485 ALSSpecificConfig *sconf = &ctx->sconf;
1488 if (!avctx->extradata) {
1489 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1493 if (read_specific_config(ctx)) {
1494 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1499 if (check_specific_config(ctx)) {
1505 ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1507 if (sconf->floating) {
1508 avctx->sample_fmt = SAMPLE_FMT_FLT;
1509 avctx->bits_per_raw_sample = 32;
1511 avctx->sample_fmt = sconf->resolution > 1
1512 ? SAMPLE_FMT_S32 : SAMPLE_FMT_S16;
1513 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1516 // set maximum Rice parameter for progressive decoding based on resolution
1517 // This is not specified in 14496-3 but actually done by the reference
1518 // codec RM22 revision 2.
1519 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1521 // set lag value for long-term prediction
1522 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1523 (avctx->sample_rate >= 192000);
1525 // allocate quantized parcor coefficient buffer
1526 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1528 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1529 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1530 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1531 num_buffers * sconf->max_order);
1532 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1533 num_buffers * sconf->max_order);
1534 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1537 if (!ctx->quant_cof || !ctx->lpc_cof ||
1538 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1539 !ctx->lpc_cof_reversed_buffer) {
1540 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1541 return AVERROR(ENOMEM);
1544 // assign quantized parcor coefficient buffers
1545 for (c = 0; c < num_buffers; c++) {
1546 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1547 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1550 // allocate and assign lag and gain data buffer for ltp mode
1551 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1552 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1553 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1554 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1557 if (!ctx->use_ltp || !ctx->ltp_lag ||
1558 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1559 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1561 return AVERROR(ENOMEM);
1564 for (c = 0; c < num_buffers; c++)
1565 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1567 // allocate and assign channel data buffer for mcc mode
1568 if (sconf->mc_coding) {
1569 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1570 num_buffers * num_buffers);
1571 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1573 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1576 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1577 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1579 return AVERROR(ENOMEM);
1582 for (c = 0; c < num_buffers; c++)
1583 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1585 ctx->chan_data = NULL;
1586 ctx->chan_data_buffer = NULL;
1587 ctx->reverted_channels = NULL;
1590 avctx->frame_size = sconf->frame_length;
1591 channel_size = sconf->frame_length + sconf->max_order;
1593 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1594 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1595 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1597 // allocate previous raw sample buffer
1598 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1599 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1601 return AVERROR(ENOMEM);
1604 // assign raw samples buffers
1605 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1606 for (c = 1; c < avctx->channels; c++)
1607 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1613 /** Flushes (resets) the frame ID after seeking.
1615 static av_cold void flush(AVCodecContext *avctx)
1617 ALSDecContext *ctx = avctx->priv_data;
1623 AVCodec als_decoder = {
1627 sizeof(ALSDecContext),
1633 .capabilities = CODEC_CAP_SUBFRAMES,
1634 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),