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"
40 #include "libavutil/samplefmt.h"
41 #include "libavutil/crc.h"
45 /** Rice parameters and corresponding index offsets for decoding the
46 * indices of scaled PARCOR values. The table chosen is set globally
47 * by the encoder and stored in ALSSpecificConfig.
49 static const int8_t parcor_rice_table[3][20][2] = {
50 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
51 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
52 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
53 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
54 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
55 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
56 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
57 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
58 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
59 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
60 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
61 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
65 /** Scaled PARCOR values used for the first two PARCOR coefficients.
66 * To be indexed by the Rice coded indices.
67 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
68 * Actual values are divided by 32 in order to be stored in 16 bits.
70 static const int16_t parcor_scaled_values[] = {
71 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
72 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
73 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
74 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
75 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
76 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
77 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
78 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
79 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
80 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
81 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
82 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
83 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
84 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
85 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
86 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
87 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
88 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
89 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
90 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
91 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
92 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
93 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
94 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
95 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
96 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
97 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
98 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
99 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
100 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
101 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
102 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
106 /** Gain values of p(0) for long-term prediction.
107 * To be indexed by the Rice coded indices.
109 static const uint8_t ltp_gain_values [4][4] = {
117 /** Inter-channel weighting factors for multi-channel correlation.
118 * To be indexed by the Rice coded indices.
120 static const int16_t mcc_weightings[] = {
121 204, 192, 179, 166, 153, 140, 128, 115,
122 102, 89, 76, 64, 51, 38, 25, 12,
123 0, -12, -25, -38, -51, -64, -76, -89,
124 -102, -115, -128, -140, -153, -166, -179, -192
128 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
130 static const uint8_t tail_code[16][6] = {
131 { 74, 44, 25, 13, 7, 3},
132 { 68, 42, 24, 13, 7, 3},
133 { 58, 39, 23, 13, 7, 3},
134 {126, 70, 37, 19, 10, 5},
135 {132, 70, 37, 20, 10, 5},
136 {124, 70, 38, 20, 10, 5},
137 {120, 69, 37, 20, 11, 5},
138 {116, 67, 37, 20, 11, 5},
139 {108, 66, 36, 20, 10, 5},
140 {102, 62, 36, 20, 10, 5},
141 { 88, 58, 34, 19, 10, 5},
142 {162, 89, 49, 25, 13, 7},
143 {156, 87, 49, 26, 14, 7},
144 {150, 86, 47, 26, 14, 7},
145 {142, 84, 47, 26, 14, 7},
146 {131, 79, 46, 26, 14, 7}
158 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
159 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
160 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
161 int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
162 int frame_length; ///< frame length for each frame (last frame may differ)
163 int ra_distance; ///< distance between RA frames (in frames, 0...255)
164 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
165 int adapt_order; ///< adaptive order: 1 = on, 0 = off
166 int coef_table; ///< table index of Rice code parameters
167 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
168 int max_order; ///< maximum prediction order (0..1023)
169 int block_switching; ///< number of block switching levels
170 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
171 int sb_part; ///< sub-block partition
172 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
173 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
174 int chan_config; ///< indicates that a chan_config_info field is present
175 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
176 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
177 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
178 int *chan_pos; ///< original channel positions
179 int crc_enabled; ///< enable Cyclic Redundancy Checksum
194 AVCodecContext *avctx;
196 ALSSpecificConfig sconf;
199 const AVCRC *crc_table;
200 uint32_t crc_org; ///< CRC value of the original input data
201 uint32_t crc; ///< CRC value calculated from decoded data
202 unsigned int cur_frame_length; ///< length of the current frame to decode
203 unsigned int frame_id; ///< the frame ID / number of the current frame
204 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
205 unsigned int num_blocks; ///< number of blocks used in the current frame
206 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
207 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
208 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
209 int ltp_lag_length; ///< number of bits used for ltp lag value
210 int *const_block; ///< contains const_block flags for all channels
211 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
212 unsigned int *opt_order; ///< contains opt_order flags for all channels
213 int *store_prev_samples; ///< contains store_prev_samples flags for all channels
214 int *use_ltp; ///< contains use_ltp flags for all channels
215 int *ltp_lag; ///< contains ltp lag values for all channels
216 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
217 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
218 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
219 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
220 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
221 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
222 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
223 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
224 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
225 int *reverted_channels; ///< stores a flag for each reverted channel
226 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
227 int32_t **raw_samples; ///< decoded raw samples for each channel
228 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
229 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
234 unsigned int block_length; ///< number of samples within the block
235 unsigned int ra_block; ///< if true, this is a random access block
236 int *const_block; ///< if true, this is a constant value block
237 int js_blocks; ///< true if this block contains a difference signal
238 unsigned int *shift_lsbs; ///< shift of values for this block
239 unsigned int *opt_order; ///< prediction order of this block
240 int *store_prev_samples;///< if true, carryover samples have to be stored
241 int *use_ltp; ///< if true, long-term prediction is used
242 int *ltp_lag; ///< lag value for long-term prediction
243 int *ltp_gain; ///< gain values for ltp 5-tap filter
244 int32_t *quant_cof; ///< quantized parcor coefficients
245 int32_t *lpc_cof; ///< coefficients of the direct form prediction
246 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
247 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
248 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
252 static av_cold void dprint_specific_config(ALSDecContext *ctx)
255 AVCodecContext *avctx = ctx->avctx;
256 ALSSpecificConfig *sconf = &ctx->sconf;
258 av_dlog(avctx, "resolution = %i\n", sconf->resolution);
259 av_dlog(avctx, "floating = %i\n", sconf->floating);
260 av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
261 av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
262 av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
263 av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
264 av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
265 av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
266 av_dlog(avctx, "max_order = %i\n", sconf->max_order);
267 av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
268 av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
269 av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
270 av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
271 av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
272 av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
273 av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
274 av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
275 av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
280 /** Read an ALSSpecificConfig from a buffer into the output struct.
282 static av_cold int read_specific_config(ALSDecContext *ctx)
286 int i, config_offset;
287 MPEG4AudioConfig m4ac;
288 ALSSpecificConfig *sconf = &ctx->sconf;
289 AVCodecContext *avctx = ctx->avctx;
290 uint32_t als_id, header_size, trailer_size;
292 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
294 config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
295 avctx->extradata_size * 8, 1);
297 if (config_offset < 0)
300 skip_bits_long(&gb, config_offset);
302 if (get_bits_left(&gb) < (30 << 3))
305 // read the fixed items
306 als_id = get_bits_long(&gb, 32);
307 avctx->sample_rate = m4ac.sample_rate;
308 skip_bits_long(&gb, 32); // sample rate already known
309 sconf->samples = get_bits_long(&gb, 32);
310 avctx->channels = m4ac.channels;
311 skip_bits(&gb, 16); // number of channels already knwon
312 skip_bits(&gb, 3); // skip file_type
313 sconf->resolution = get_bits(&gb, 3);
314 sconf->floating = get_bits1(&gb);
315 sconf->msb_first = get_bits1(&gb);
316 sconf->frame_length = get_bits(&gb, 16) + 1;
317 sconf->ra_distance = get_bits(&gb, 8);
318 sconf->ra_flag = get_bits(&gb, 2);
319 sconf->adapt_order = get_bits1(&gb);
320 sconf->coef_table = get_bits(&gb, 2);
321 sconf->long_term_prediction = get_bits1(&gb);
322 sconf->max_order = get_bits(&gb, 10);
323 sconf->block_switching = get_bits(&gb, 2);
324 sconf->bgmc = get_bits1(&gb);
325 sconf->sb_part = get_bits1(&gb);
326 sconf->joint_stereo = get_bits1(&gb);
327 sconf->mc_coding = get_bits1(&gb);
328 sconf->chan_config = get_bits1(&gb);
329 sconf->chan_sort = get_bits1(&gb);
330 sconf->crc_enabled = get_bits1(&gb);
331 sconf->rlslms = get_bits1(&gb);
332 skip_bits(&gb, 5); // skip 5 reserved bits
333 skip_bits1(&gb); // skip aux_data_enabled
336 // check for ALSSpecificConfig struct
337 if (als_id != MKBETAG('A','L','S','\0'))
340 ctx->cur_frame_length = sconf->frame_length;
342 // read channel config
343 if (sconf->chan_config)
344 sconf->chan_config_info = get_bits(&gb, 16);
345 // TODO: use this to set avctx->channel_layout
348 // read channel sorting
349 if (sconf->chan_sort && avctx->channels > 1) {
350 int chan_pos_bits = av_ceil_log2(avctx->channels);
351 int bits_needed = avctx->channels * chan_pos_bits + 7;
352 if (get_bits_left(&gb) < bits_needed)
355 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
356 return AVERROR(ENOMEM);
358 for (i = 0; i < avctx->channels; i++)
359 sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
362 // TODO: use this to actually do channel sorting
364 sconf->chan_sort = 0;
368 // read fixed header and trailer sizes,
369 // if size = 0xFFFFFFFF then there is no data field!
370 if (get_bits_left(&gb) < 64)
373 header_size = get_bits_long(&gb, 32);
374 trailer_size = get_bits_long(&gb, 32);
375 if (header_size == 0xFFFFFFFF)
377 if (trailer_size == 0xFFFFFFFF)
380 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
383 // skip the header and trailer data
384 if (get_bits_left(&gb) < ht_size)
387 if (ht_size > INT32_MAX)
390 skip_bits_long(&gb, ht_size);
393 // initialize CRC calculation
394 if (sconf->crc_enabled) {
395 if (get_bits_left(&gb) < 32)
398 if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
399 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
400 ctx->crc = 0xFFFFFFFF;
401 ctx->crc_org = ~get_bits_long(&gb, 32);
403 skip_bits_long(&gb, 32);
407 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
409 dprint_specific_config(ctx);
415 /** Check the ALSSpecificConfig for unsupported features.
417 static int check_specific_config(ALSDecContext *ctx)
419 ALSSpecificConfig *sconf = &ctx->sconf;
422 // report unsupported feature and set error value
423 #define MISSING_ERR(cond, str, errval) \
426 av_log_missing_feature(ctx->avctx, str, 0); \
431 MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
432 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
433 MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
439 /** Parse the bs_info field to extract the block partitioning used in
440 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
442 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
443 unsigned int div, unsigned int **div_blocks,
444 unsigned int *num_blocks)
446 if (n < 31 && ((bs_info << n) & 0x40000000)) {
447 // if the level is valid and the investigated bit n is set
448 // then recursively check both children at bits (2n+1) and (2n+2)
451 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
452 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
454 // else the bit is not set or the last level has been reached
455 // (bit implicitly not set)
463 /** Read and decode a Rice codeword.
465 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
467 int max = get_bits_left(gb) - k;
468 int q = get_unary(gb, 0, max);
469 int r = k ? get_bits1(gb) : !(q & 1);
473 q += get_bits_long(gb, k - 1);
481 /** Convert PARCOR coefficient k to direct filter coefficient.
483 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
487 for (i = 0, j = k - 1; i < j; i++, j--) {
488 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
489 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
493 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
499 /** Read block switching field if necessary and set actual block sizes.
500 * Also assure that the block sizes of the last frame correspond to the
501 * actual number of samples.
503 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
506 ALSSpecificConfig *sconf = &ctx->sconf;
507 GetBitContext *gb = &ctx->gb;
508 unsigned int *ptr_div_blocks = div_blocks;
511 if (sconf->block_switching) {
512 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
513 *bs_info = get_bits_long(gb, bs_info_len);
514 *bs_info <<= (32 - bs_info_len);
518 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
520 // The last frame may have an overdetermined block structure given in
521 // the bitstream. In that case the defined block structure would need
522 // more samples than available to be consistent.
523 // The block structure is actually used but the block sizes are adapted
524 // to fit the actual number of available samples.
525 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
526 // This results in the actual block sizes: 2 2 1 0.
527 // This is not specified in 14496-3 but actually done by the reference
528 // codec RM22 revision 2.
529 // This appears to happen in case of an odd number of samples in the last
530 // frame which is actually not allowed by the block length switching part
532 // The ALS conformance files feature an odd number of samples in the last
535 for (b = 0; b < ctx->num_blocks; b++)
536 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
538 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
539 unsigned int remaining = ctx->cur_frame_length;
541 for (b = 0; b < ctx->num_blocks; b++) {
542 if (remaining <= div_blocks[b]) {
543 div_blocks[b] = remaining;
544 ctx->num_blocks = b + 1;
548 remaining -= div_blocks[b];
554 /** Read the block data for a constant block
556 static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
558 ALSSpecificConfig *sconf = &ctx->sconf;
559 AVCodecContext *avctx = ctx->avctx;
560 GetBitContext *gb = &ctx->gb;
562 if (bd->block_length <= 0)
563 return AVERROR_INVALIDDATA;
565 *bd->raw_samples = 0;
566 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
567 bd->js_blocks = get_bits1(gb);
569 // skip 5 reserved bits
572 if (*bd->const_block) {
573 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
574 *bd->raw_samples = get_sbits_long(gb, const_val_bits);
577 // ensure constant block decoding by reusing this field
578 *bd->const_block = 1;
584 /** Decode the block data for a constant block
586 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
588 int smp = bd->block_length - 1;
589 int32_t val = *bd->raw_samples;
590 int32_t *dst = bd->raw_samples + 1;
592 // write raw samples into buffer
598 /** Read the block data for a non-constant block
600 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
602 ALSSpecificConfig *sconf = &ctx->sconf;
603 AVCodecContext *avctx = ctx->avctx;
604 GetBitContext *gb = &ctx->gb;
608 unsigned int sub_blocks, log2_sub_blocks, sb_length;
609 unsigned int start = 0;
610 unsigned int opt_order;
612 int32_t *quant_cof = bd->quant_cof;
613 int32_t *current_res;
616 // ensure variable block decoding by reusing this field
617 *bd->const_block = 0;
620 bd->js_blocks = get_bits1(gb);
622 opt_order = *bd->opt_order;
624 // determine the number of subblocks for entropy decoding
625 if (!sconf->bgmc && !sconf->sb_part) {
628 if (sconf->bgmc && sconf->sb_part)
629 log2_sub_blocks = get_bits(gb, 2);
631 log2_sub_blocks = 2 * get_bits1(gb);
634 sub_blocks = 1 << log2_sub_blocks;
636 // do not continue in case of a damaged stream since
637 // block_length must be evenly divisible by sub_blocks
638 if (bd->block_length & (sub_blocks - 1)) {
639 av_log(avctx, AV_LOG_WARNING,
640 "Block length is not evenly divisible by the number of subblocks.\n");
644 sb_length = bd->block_length >> log2_sub_blocks;
647 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
648 for (k = 1; k < sub_blocks; k++)
649 s[k] = s[k - 1] + decode_rice(gb, 2);
651 for (k = 0; k < sub_blocks; k++) {
656 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
657 for (k = 1; k < sub_blocks; k++)
658 s[k] = s[k - 1] + decode_rice(gb, 0);
660 for (k = 1; k < sub_blocks; k++)
662 av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
663 return AVERROR_INVALIDDATA;
667 *bd->shift_lsbs = get_bits(gb, 4) + 1;
669 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
672 if (!sconf->rlslms) {
673 if (sconf->adapt_order) {
674 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
675 2, sconf->max_order + 1));
676 *bd->opt_order = get_bits(gb, opt_order_length);
677 if (*bd->opt_order > sconf->max_order) {
678 *bd->opt_order = sconf->max_order;
679 av_log(avctx, AV_LOG_ERROR, "Predictor order too large!\n");
680 return AVERROR_INVALIDDATA;
683 *bd->opt_order = sconf->max_order;
686 opt_order = *bd->opt_order;
691 if (sconf->coef_table == 3) {
694 // read coefficient 0
695 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
697 // read coefficient 1
699 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
701 // read coefficients 2 to opt_order
702 for (k = 2; k < opt_order; k++)
703 quant_cof[k] = get_bits(gb, 7);
708 // read coefficient 0 to 19
709 k_max = FFMIN(opt_order, 20);
710 for (k = 0; k < k_max; k++) {
711 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
712 int offset = parcor_rice_table[sconf->coef_table][k][0];
713 quant_cof[k] = decode_rice(gb, rice_param) + offset;
714 if (quant_cof[k] < -64 || quant_cof[k] > 63) {
715 av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range\n", quant_cof[k]);
716 return AVERROR_INVALIDDATA;
720 // read coefficients 20 to 126
721 k_max = FFMIN(opt_order, 127);
722 for (; k < k_max; k++)
723 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
725 // read coefficients 127 to opt_order
726 for (; k < opt_order; k++)
727 quant_cof[k] = decode_rice(gb, 1);
729 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
732 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
735 for (k = 2; k < opt_order; k++)
736 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
740 // read LTP gain and lag values
741 if (sconf->long_term_prediction) {
742 *bd->use_ltp = get_bits1(gb);
747 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
748 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
750 r = get_unary(gb, 0, 3);
752 bd->ltp_gain[2] = ltp_gain_values[r][c];
754 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
755 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
757 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
758 *bd->ltp_lag += FFMAX(4, opt_order + 1);
762 // read first value and residuals in case of a random access block
765 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
767 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
769 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
771 start = FFMIN(opt_order, 3);
774 // read all residuals
778 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
780 // read most significant bits
785 ff_bgmc_decode_init(gb, &high, &low, &value);
787 current_res = bd->raw_samples + start;
789 for (sb = 0; sb < sub_blocks; sb++) {
790 unsigned int sb_len = sb_length - (sb ? 0 : start);
792 k [sb] = s[sb] > b ? s[sb] - b : 0;
793 delta[sb] = 5 - s[sb] + k[sb];
795 ff_bgmc_decode(gb, sb_len, current_res,
796 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
798 current_res += sb_len;
801 ff_bgmc_decode_end(gb);
804 // read least significant bits and tails
805 current_res = bd->raw_samples + start;
807 for (sb = 0; sb < sub_blocks; sb++, start = 0) {
808 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
809 unsigned int cur_k = k[sb];
810 unsigned int cur_s = s[sb];
812 for (; start < sb_length; start++) {
813 int32_t res = *current_res;
815 if (res == cur_tail_code) {
816 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
819 res = decode_rice(gb, cur_s);
822 res += (max_msb ) << cur_k;
824 res -= (max_msb - 1) << cur_k;
827 if (res > cur_tail_code)
837 res |= get_bits_long(gb, cur_k);
841 *current_res++ = res;
845 current_res = bd->raw_samples + start;
847 for (sb = 0; sb < sub_blocks; sb++, start = 0)
848 for (; start < sb_length; start++)
849 *current_res++ = decode_rice(gb, s[sb]);
852 if (!sconf->mc_coding || ctx->js_switch)
859 /** Decode the block data for a non-constant block
861 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
863 ALSSpecificConfig *sconf = &ctx->sconf;
864 unsigned int block_length = bd->block_length;
865 unsigned int smp = 0;
867 int opt_order = *bd->opt_order;
870 int32_t *quant_cof = bd->quant_cof;
871 int32_t *lpc_cof = bd->lpc_cof;
872 int32_t *raw_samples = bd->raw_samples;
873 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
874 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
876 // reverse long-term prediction
880 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
881 int center = ltp_smp - *bd->ltp_lag;
882 int begin = FFMAX(0, center - 2);
883 int end = center + 3;
884 int tab = 5 - (end - begin);
889 for (base = begin; base < end; base++, tab++)
890 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
892 raw_samples[ltp_smp] += y >> 7;
896 // reconstruct all samples from residuals
898 for (smp = 0; smp < opt_order; smp++) {
901 for (sb = 0; sb < smp; sb++)
902 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
904 *raw_samples++ -= y >> 20;
905 parcor_to_lpc(smp, quant_cof, lpc_cof);
908 for (k = 0; k < opt_order; k++)
909 parcor_to_lpc(k, quant_cof, lpc_cof);
911 // store previous samples in case that they have to be altered
912 if (*bd->store_prev_samples)
913 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
914 sizeof(*bd->prev_raw_samples) * sconf->max_order);
916 // reconstruct difference signal for prediction (joint-stereo)
917 if (bd->js_blocks && bd->raw_other) {
918 int32_t *left, *right;
920 if (bd->raw_other > raw_samples) { // D = R - L
922 right = bd->raw_other;
923 } else { // D = R - L
924 left = bd->raw_other;
928 for (sb = -1; sb >= -sconf->max_order; sb--)
929 raw_samples[sb] = right[sb] - left[sb];
932 // reconstruct shifted signal
934 for (sb = -1; sb >= -sconf->max_order; sb--)
935 raw_samples[sb] >>= *bd->shift_lsbs;
938 // reverse linear prediction coefficients for efficiency
939 lpc_cof = lpc_cof + opt_order;
941 for (sb = 0; sb < opt_order; sb++)
942 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
944 // reconstruct raw samples
945 raw_samples = bd->raw_samples + smp;
946 lpc_cof = lpc_cof_reversed + opt_order;
948 for (; raw_samples < raw_samples_end; raw_samples++) {
951 for (sb = -opt_order; sb < 0; sb++)
952 y += MUL64(lpc_cof[sb], raw_samples[sb]);
954 *raw_samples -= y >> 20;
957 raw_samples = bd->raw_samples;
959 // restore previous samples in case that they have been altered
960 if (*bd->store_prev_samples)
961 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
962 sizeof(*raw_samples) * sconf->max_order);
968 /** Read the block data.
970 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
972 GetBitContext *gb = &ctx->gb;
976 // read block type flag and read the samples accordingly
978 if ((ret = read_var_block_data(ctx, bd)) < 0)
981 if ((ret = read_const_block_data(ctx, bd)) < 0)
989 /** Decode the block data.
991 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
995 // read block type flag and read the samples accordingly
996 if (*bd->const_block)
997 decode_const_block_data(ctx, bd);
998 else if (decode_var_block_data(ctx, bd))
1001 // TODO: read RLSLMS extension data
1003 if (*bd->shift_lsbs)
1004 for (smp = 0; smp < bd->block_length; smp++)
1005 bd->raw_samples[smp] <<= *bd->shift_lsbs;
1011 /** Read and decode block data successively.
1013 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1017 ret = read_block(ctx, bd);
1022 ret = decode_block(ctx, bd);
1028 /** Compute the number of samples left to decode for the current frame and
1029 * sets these samples to zero.
1031 static void zero_remaining(unsigned int b, unsigned int b_max,
1032 const unsigned int *div_blocks, int32_t *buf)
1034 unsigned int count = 0;
1037 count += div_blocks[b++];
1040 memset(buf, 0, sizeof(*buf) * count);
1044 /** Decode blocks independently.
1046 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1047 unsigned int c, const unsigned int *div_blocks,
1048 unsigned int *js_blocks)
1051 ALSBlockData bd = { 0 };
1053 bd.ra_block = ra_frame;
1054 bd.const_block = ctx->const_block;
1055 bd.shift_lsbs = ctx->shift_lsbs;
1056 bd.opt_order = ctx->opt_order;
1057 bd.store_prev_samples = ctx->store_prev_samples;
1058 bd.use_ltp = ctx->use_ltp;
1059 bd.ltp_lag = ctx->ltp_lag;
1060 bd.ltp_gain = ctx->ltp_gain[0];
1061 bd.quant_cof = ctx->quant_cof[0];
1062 bd.lpc_cof = ctx->lpc_cof[0];
1063 bd.prev_raw_samples = ctx->prev_raw_samples;
1064 bd.raw_samples = ctx->raw_samples[c];
1067 for (b = 0; b < ctx->num_blocks; b++) {
1068 bd.block_length = div_blocks[b];
1070 if (read_decode_block(ctx, &bd)) {
1071 // damaged block, write zero for the rest of the frame
1072 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1075 bd.raw_samples += div_blocks[b];
1083 /** Decode blocks dependently.
1085 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1086 unsigned int c, const unsigned int *div_blocks,
1087 unsigned int *js_blocks)
1089 ALSSpecificConfig *sconf = &ctx->sconf;
1090 unsigned int offset = 0;
1092 ALSBlockData bd[2] = { { 0 } };
1094 bd[0].ra_block = ra_frame;
1095 bd[0].const_block = ctx->const_block;
1096 bd[0].shift_lsbs = ctx->shift_lsbs;
1097 bd[0].opt_order = ctx->opt_order;
1098 bd[0].store_prev_samples = ctx->store_prev_samples;
1099 bd[0].use_ltp = ctx->use_ltp;
1100 bd[0].ltp_lag = ctx->ltp_lag;
1101 bd[0].ltp_gain = ctx->ltp_gain[0];
1102 bd[0].quant_cof = ctx->quant_cof[0];
1103 bd[0].lpc_cof = ctx->lpc_cof[0];
1104 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1105 bd[0].js_blocks = *js_blocks;
1107 bd[1].ra_block = ra_frame;
1108 bd[1].const_block = ctx->const_block;
1109 bd[1].shift_lsbs = ctx->shift_lsbs;
1110 bd[1].opt_order = ctx->opt_order;
1111 bd[1].store_prev_samples = ctx->store_prev_samples;
1112 bd[1].use_ltp = ctx->use_ltp;
1113 bd[1].ltp_lag = ctx->ltp_lag;
1114 bd[1].ltp_gain = ctx->ltp_gain[0];
1115 bd[1].quant_cof = ctx->quant_cof[0];
1116 bd[1].lpc_cof = ctx->lpc_cof[0];
1117 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1118 bd[1].js_blocks = *(js_blocks + 1);
1120 // decode all blocks
1121 for (b = 0; b < ctx->num_blocks; b++) {
1124 bd[0].block_length = div_blocks[b];
1125 bd[1].block_length = div_blocks[b];
1127 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1128 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1130 bd[0].raw_other = bd[1].raw_samples;
1131 bd[1].raw_other = bd[0].raw_samples;
1133 if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1134 // damaged block, write zero for the rest of the frame
1135 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1136 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1140 // reconstruct joint-stereo blocks
1141 if (bd[0].js_blocks) {
1142 if (bd[1].js_blocks)
1143 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1145 for (s = 0; s < div_blocks[b]; s++)
1146 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1147 } else if (bd[1].js_blocks) {
1148 for (s = 0; s < div_blocks[b]; s++)
1149 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1152 offset += div_blocks[b];
1157 // store carryover raw samples,
1158 // the others channel raw samples are stored by the calling function.
1159 memmove(ctx->raw_samples[c] - sconf->max_order,
1160 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1161 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1167 /** Read the channel data.
1169 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1171 GetBitContext *gb = &ctx->gb;
1172 ALSChannelData *current = cd;
1173 unsigned int channels = ctx->avctx->channels;
1176 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1177 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1179 if (current->master_channel >= channels) {
1180 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1184 if (current->master_channel != c) {
1185 current->time_diff_flag = get_bits1(gb);
1186 current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1187 current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 31)];
1188 current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1190 if (current->time_diff_flag) {
1191 current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1192 current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1193 current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1195 current->time_diff_sign = get_bits1(gb);
1196 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1204 if (entries == channels) {
1205 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1214 /** Recursively reverts the inter-channel correlation for a block.
1216 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1217 ALSChannelData **cd, int *reverted,
1218 unsigned int offset, int c)
1220 ALSChannelData *ch = cd[c];
1221 unsigned int dep = 0;
1222 unsigned int channels = ctx->avctx->channels;
1229 while (dep < channels && !ch[dep].stop_flag) {
1230 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1231 ch[dep].master_channel);
1236 if (dep == channels) {
1237 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1241 bd->const_block = ctx->const_block + c;
1242 bd->shift_lsbs = ctx->shift_lsbs + c;
1243 bd->opt_order = ctx->opt_order + c;
1244 bd->store_prev_samples = ctx->store_prev_samples + c;
1245 bd->use_ltp = ctx->use_ltp + c;
1246 bd->ltp_lag = ctx->ltp_lag + c;
1247 bd->ltp_gain = ctx->ltp_gain[c];
1248 bd->lpc_cof = ctx->lpc_cof[c];
1249 bd->quant_cof = ctx->quant_cof[c];
1250 bd->raw_samples = ctx->raw_samples[c] + offset;
1253 while (!ch[dep].stop_flag) {
1255 unsigned int begin = 1;
1256 unsigned int end = bd->block_length - 1;
1258 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1260 if (ch[dep].time_diff_flag) {
1261 int t = ch[dep].time_diff_index;
1263 if (ch[dep].time_diff_sign) {
1270 for (smp = begin; smp < end; smp++) {
1272 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1273 MUL64(ch[dep].weighting[1], master[smp ]) +
1274 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1275 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1276 MUL64(ch[dep].weighting[4], master[smp + t]) +
1277 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1279 bd->raw_samples[smp] += y >> 7;
1282 for (smp = begin; smp < end; smp++) {
1284 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1285 MUL64(ch[dep].weighting[1], master[smp ]) +
1286 MUL64(ch[dep].weighting[2], master[smp + 1]);
1288 bd->raw_samples[smp] += y >> 7;
1299 /** Read the frame data.
1301 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1303 ALSSpecificConfig *sconf = &ctx->sconf;
1304 AVCodecContext *avctx = ctx->avctx;
1305 GetBitContext *gb = &ctx->gb;
1306 unsigned int div_blocks[32]; ///< block sizes.
1308 unsigned int js_blocks[2];
1310 uint32_t bs_info = 0;
1312 // skip the size of the ra unit if present in the frame
1313 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1314 skip_bits_long(gb, 32);
1316 if (sconf->mc_coding && sconf->joint_stereo) {
1317 ctx->js_switch = get_bits1(gb);
1321 if (!sconf->mc_coding || ctx->js_switch) {
1322 int independent_bs = !sconf->joint_stereo;
1324 for (c = 0; c < avctx->channels; c++) {
1328 get_block_sizes(ctx, div_blocks, &bs_info);
1330 // if joint_stereo and block_switching is set, independent decoding
1331 // is signaled via the first bit of bs_info
1332 if (sconf->joint_stereo && sconf->block_switching)
1336 // if this is the last channel, it has to be decoded independently
1337 if (c == avctx->channels - 1)
1340 if (independent_bs) {
1341 if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1346 if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1352 // store carryover raw samples
1353 memmove(ctx->raw_samples[c] - sconf->max_order,
1354 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1355 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1357 } else { // multi-channel coding
1358 ALSBlockData bd = { 0 };
1360 int *reverted_channels = ctx->reverted_channels;
1361 unsigned int offset = 0;
1363 for (c = 0; c < avctx->channels; c++)
1364 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1365 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1369 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1371 bd.ra_block = ra_frame;
1372 bd.prev_raw_samples = ctx->prev_raw_samples;
1374 get_block_sizes(ctx, div_blocks, &bs_info);
1376 for (b = 0; b < ctx->num_blocks; b++) {
1377 bd.block_length = div_blocks[b];
1379 for (c = 0; c < avctx->channels; c++) {
1380 bd.const_block = ctx->const_block + c;
1381 bd.shift_lsbs = ctx->shift_lsbs + c;
1382 bd.opt_order = ctx->opt_order + c;
1383 bd.store_prev_samples = ctx->store_prev_samples + c;
1384 bd.use_ltp = ctx->use_ltp + c;
1385 bd.ltp_lag = ctx->ltp_lag + c;
1386 bd.ltp_gain = ctx->ltp_gain[c];
1387 bd.lpc_cof = ctx->lpc_cof[c];
1388 bd.quant_cof = ctx->quant_cof[c];
1389 bd.raw_samples = ctx->raw_samples[c] + offset;
1390 bd.raw_other = NULL;
1392 if ((ret = read_block(ctx, &bd)) < 0)
1394 if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1398 for (c = 0; c < avctx->channels; c++)
1399 if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1400 reverted_channels, offset, c))
1403 for (c = 0; c < avctx->channels; c++) {
1404 bd.const_block = ctx->const_block + c;
1405 bd.shift_lsbs = ctx->shift_lsbs + c;
1406 bd.opt_order = ctx->opt_order + c;
1407 bd.store_prev_samples = ctx->store_prev_samples + c;
1408 bd.use_ltp = ctx->use_ltp + c;
1409 bd.ltp_lag = ctx->ltp_lag + c;
1410 bd.ltp_gain = ctx->ltp_gain[c];
1411 bd.lpc_cof = ctx->lpc_cof[c];
1412 bd.quant_cof = ctx->quant_cof[c];
1413 bd.raw_samples = ctx->raw_samples[c] + offset;
1415 if ((ret = decode_block(ctx, &bd)) < 0)
1419 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1420 offset += div_blocks[b];
1424 // store carryover raw samples
1425 for (c = 0; c < avctx->channels; c++)
1426 memmove(ctx->raw_samples[c] - sconf->max_order,
1427 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1428 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1431 // TODO: read_diff_float_data
1437 /** Decode an ALS frame.
1439 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1442 ALSDecContext *ctx = avctx->priv_data;
1443 ALSSpecificConfig *sconf = &ctx->sconf;
1444 const uint8_t *buffer = avpkt->data;
1445 int buffer_size = avpkt->size;
1446 int invalid_frame, ret;
1447 unsigned int c, sample, ra_frame, bytes_read, shift;
1449 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1451 // In the case that the distance between random access frames is set to zero
1452 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1453 // For the first frame, if prediction is used, all samples used from the
1454 // previous frame are assumed to be zero.
1455 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1457 // the last frame to decode might have a different length
1458 if (sconf->samples != 0xFFFFFFFF)
1459 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1460 sconf->frame_length);
1462 ctx->cur_frame_length = sconf->frame_length;
1464 // decode the frame data
1465 if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1466 av_log(ctx->avctx, AV_LOG_WARNING,
1467 "Reading frame data failed. Skipping RA unit.\n");
1471 /* get output buffer */
1472 ctx->frame.nb_samples = ctx->cur_frame_length;
1473 if ((ret = ff_get_buffer(avctx, &ctx->frame)) < 0) {
1474 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1478 // transform decoded frame into output format
1479 #define INTERLEAVE_OUTPUT(bps) \
1481 int##bps##_t *dest = (int##bps##_t*)ctx->frame.data[0]; \
1482 shift = bps - ctx->avctx->bits_per_raw_sample; \
1483 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1484 for (c = 0; c < avctx->channels; c++) \
1485 *dest++ = ctx->raw_samples[c][sample] << shift; \
1488 if (ctx->avctx->bits_per_raw_sample <= 16) {
1489 INTERLEAVE_OUTPUT(16)
1491 INTERLEAVE_OUTPUT(32)
1495 if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1496 int swap = HAVE_BIGENDIAN != sconf->msb_first;
1498 if (ctx->avctx->bits_per_raw_sample == 24) {
1499 int32_t *src = (int32_t *)ctx->frame.data[0];
1502 sample < ctx->cur_frame_length * avctx->channels;
1507 v = av_bswap32(src[sample]);
1510 if (!HAVE_BIGENDIAN)
1513 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1516 uint8_t *crc_source;
1519 if (ctx->avctx->bits_per_raw_sample <= 16) {
1520 int16_t *src = (int16_t*) ctx->frame.data[0];
1521 int16_t *dest = (int16_t*) ctx->crc_buffer;
1523 sample < ctx->cur_frame_length * avctx->channels;
1525 *dest++ = av_bswap16(src[sample]);
1527 ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1528 (uint32_t *)ctx->frame.data[0],
1529 ctx->cur_frame_length * avctx->channels);
1531 crc_source = ctx->crc_buffer;
1533 crc_source = ctx->frame.data[0];
1536 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1537 ctx->cur_frame_length * avctx->channels *
1538 av_get_bytes_per_sample(avctx->sample_fmt));
1542 // check CRC sums if this is the last frame
1543 if (ctx->cur_frame_length != sconf->frame_length &&
1544 ctx->crc_org != ctx->crc) {
1545 av_log(avctx, AV_LOG_ERROR, "CRC error!\n");
1550 *(AVFrame *)data = ctx->frame;
1553 bytes_read = invalid_frame ? buffer_size :
1554 (get_bits_count(&ctx->gb) + 7) >> 3;
1560 /** Uninitialize the ALS decoder.
1562 static av_cold int decode_end(AVCodecContext *avctx)
1564 ALSDecContext *ctx = avctx->priv_data;
1566 av_freep(&ctx->sconf.chan_pos);
1568 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1570 av_freep(&ctx->const_block);
1571 av_freep(&ctx->shift_lsbs);
1572 av_freep(&ctx->opt_order);
1573 av_freep(&ctx->store_prev_samples);
1574 av_freep(&ctx->use_ltp);
1575 av_freep(&ctx->ltp_lag);
1576 av_freep(&ctx->ltp_gain);
1577 av_freep(&ctx->ltp_gain_buffer);
1578 av_freep(&ctx->quant_cof);
1579 av_freep(&ctx->lpc_cof);
1580 av_freep(&ctx->quant_cof_buffer);
1581 av_freep(&ctx->lpc_cof_buffer);
1582 av_freep(&ctx->lpc_cof_reversed_buffer);
1583 av_freep(&ctx->prev_raw_samples);
1584 av_freep(&ctx->raw_samples);
1585 av_freep(&ctx->raw_buffer);
1586 av_freep(&ctx->chan_data);
1587 av_freep(&ctx->chan_data_buffer);
1588 av_freep(&ctx->reverted_channels);
1589 av_freep(&ctx->crc_buffer);
1595 /** Initialize the ALS decoder.
1597 static av_cold int decode_init(AVCodecContext *avctx)
1600 unsigned int channel_size;
1602 ALSDecContext *ctx = avctx->priv_data;
1603 ALSSpecificConfig *sconf = &ctx->sconf;
1606 if (!avctx->extradata) {
1607 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata!\n");
1611 if (read_specific_config(ctx)) {
1612 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed!\n");
1617 if (check_specific_config(ctx)) {
1623 ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1625 if (sconf->floating) {
1626 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1627 avctx->bits_per_raw_sample = 32;
1629 avctx->sample_fmt = sconf->resolution > 1
1630 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1631 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1634 // set maximum Rice parameter for progressive decoding based on resolution
1635 // This is not specified in 14496-3 but actually done by the reference
1636 // codec RM22 revision 2.
1637 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1639 // set lag value for long-term prediction
1640 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1641 (avctx->sample_rate >= 192000);
1643 // allocate quantized parcor coefficient buffer
1644 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1646 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1647 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1648 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1649 num_buffers * sconf->max_order);
1650 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1651 num_buffers * sconf->max_order);
1652 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1655 if (!ctx->quant_cof || !ctx->lpc_cof ||
1656 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1657 !ctx->lpc_cof_reversed_buffer) {
1658 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed!\n");
1659 return AVERROR(ENOMEM);
1662 // assign quantized parcor coefficient buffers
1663 for (c = 0; c < num_buffers; c++) {
1664 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1665 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1668 // allocate and assign lag and gain data buffer for ltp mode
1669 ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1670 ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1671 ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1672 ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1673 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1674 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1675 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1676 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1679 if (!ctx->const_block || !ctx->shift_lsbs ||
1680 !ctx->opt_order || !ctx->store_prev_samples ||
1681 !ctx->use_ltp || !ctx->ltp_lag ||
1682 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1683 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed!\n");
1685 return AVERROR(ENOMEM);
1688 for (c = 0; c < num_buffers; c++)
1689 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1691 // allocate and assign channel data buffer for mcc mode
1692 if (sconf->mc_coding) {
1693 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1694 num_buffers * num_buffers);
1695 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1697 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1700 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1701 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed!\n");
1703 return AVERROR(ENOMEM);
1706 for (c = 0; c < num_buffers; c++)
1707 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1709 ctx->chan_data = NULL;
1710 ctx->chan_data_buffer = NULL;
1711 ctx->reverted_channels = NULL;
1714 channel_size = sconf->frame_length + sconf->max_order;
1716 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1717 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1718 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1720 // allocate previous raw sample buffer
1721 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1722 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed!\n");
1724 return AVERROR(ENOMEM);
1727 // assign raw samples buffers
1728 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1729 for (c = 1; c < avctx->channels; c++)
1730 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1732 // allocate crc buffer
1733 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1734 (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1735 ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1736 ctx->cur_frame_length *
1738 av_get_bytes_per_sample(avctx->sample_fmt));
1739 if (!ctx->crc_buffer) {
1740 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed!\n");
1742 return AVERROR(ENOMEM);
1746 ff_dsputil_init(&ctx->dsp, avctx);
1748 avcodec_get_frame_defaults(&ctx->frame);
1749 avctx->coded_frame = &ctx->frame;
1755 /** Flush (reset) the frame ID after seeking.
1757 static av_cold void flush(AVCodecContext *avctx)
1759 ALSDecContext *ctx = avctx->priv_data;
1765 AVCodec ff_als_decoder = {
1767 .type = AVMEDIA_TYPE_AUDIO,
1768 .id = AV_CODEC_ID_MP4ALS,
1769 .priv_data_size = sizeof(ALSDecContext),
1770 .init = decode_init,
1771 .close = decode_end,
1772 .decode = decode_frame,
1774 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1775 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),