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>
31 #include "mpeg4audio.h"
32 #include "bytestream.h"
36 #include "libavutil/samplefmt.h"
37 #include "libavutil/crc.h"
41 /** Rice parameters and corresponding index offsets for decoding the
42 * indices of scaled PARCOR values. The table chosen is set globally
43 * by the encoder and stored in ALSSpecificConfig.
45 static const int8_t parcor_rice_table[3][20][2] = {
46 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
47 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
48 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
49 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
50 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
51 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
52 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
53 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
54 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
55 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
56 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
57 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
61 /** Scaled PARCOR values used for the first two PARCOR coefficients.
62 * To be indexed by the Rice coded indices.
63 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
64 * Actual values are divided by 32 in order to be stored in 16 bits.
66 static const int16_t parcor_scaled_values[] = {
67 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
68 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
69 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
70 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
71 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
72 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
73 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
74 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
75 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
76 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
77 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
78 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
79 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
80 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
81 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
82 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
83 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
84 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
85 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
86 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
87 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
88 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
89 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
90 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
91 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
92 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
93 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
94 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
95 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
96 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
97 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
98 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
102 /** Gain values of p(0) for long-term prediction.
103 * To be indexed by the Rice coded indices.
105 static const uint8_t ltp_gain_values [4][4] = {
113 /** Inter-channel weighting factors for multi-channel correlation.
114 * To be indexed by the Rice coded indices.
116 static const int16_t mcc_weightings[] = {
117 204, 192, 179, 166, 153, 140, 128, 115,
118 102, 89, 76, 64, 51, 38, 25, 12,
119 0, -12, -25, -38, -51, -64, -76, -89,
120 -102, -115, -128, -140, -153, -166, -179, -192
124 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
126 static const uint8_t tail_code[16][6] = {
127 { 74, 44, 25, 13, 7, 3},
128 { 68, 42, 24, 13, 7, 3},
129 { 58, 39, 23, 13, 7, 3},
130 {126, 70, 37, 19, 10, 5},
131 {132, 70, 37, 20, 10, 5},
132 {124, 70, 38, 20, 10, 5},
133 {120, 69, 37, 20, 11, 5},
134 {116, 67, 37, 20, 11, 5},
135 {108, 66, 36, 20, 10, 5},
136 {102, 62, 36, 20, 10, 5},
137 { 88, 58, 34, 19, 10, 5},
138 {162, 89, 49, 25, 13, 7},
139 {156, 87, 49, 26, 14, 7},
140 {150, 86, 47, 26, 14, 7},
141 {142, 84, 47, 26, 14, 7},
142 {131, 79, 46, 26, 14, 7}
154 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
155 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
156 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
157 int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
158 int frame_length; ///< frame length for each frame (last frame may differ)
159 int ra_distance; ///< distance between RA frames (in frames, 0...255)
160 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
161 int adapt_order; ///< adaptive order: 1 = on, 0 = off
162 int coef_table; ///< table index of Rice code parameters
163 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
164 int max_order; ///< maximum prediction order (0..1023)
165 int block_switching; ///< number of block switching levels
166 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
167 int sb_part; ///< sub-block partition
168 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
169 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
170 int chan_config; ///< indicates that a chan_config_info field is present
171 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
172 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
173 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
174 int *chan_pos; ///< original channel positions
175 int crc_enabled; ///< enable Cyclic Redundancy Checksum
190 AVCodecContext *avctx;
191 ALSSpecificConfig sconf;
194 const AVCRC *crc_table;
195 uint32_t crc_org; ///< CRC value of the original input data
196 uint32_t crc; ///< CRC value calculated from decoded data
197 unsigned int cur_frame_length; ///< length of the current frame to decode
198 unsigned int frame_id; ///< the frame ID / number of the current frame
199 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
200 unsigned int cs_switch; ///< if true, channel rearrangement is done
201 unsigned int num_blocks; ///< number of blocks used in the current frame
202 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
203 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
204 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
205 int ltp_lag_length; ///< number of bits used for ltp lag value
206 int *const_block; ///< contains const_block flags for all channels
207 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
208 unsigned int *opt_order; ///< contains opt_order flags for all channels
209 int *store_prev_samples; ///< contains store_prev_samples flags for all channels
210 int *use_ltp; ///< contains use_ltp flags for all channels
211 int *ltp_lag; ///< contains ltp lag values for all channels
212 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
213 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
214 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
215 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
216 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
217 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
218 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
219 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
220 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
221 int *reverted_channels; ///< stores a flag for each reverted channel
222 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
223 int32_t **raw_samples; ///< decoded raw samples for each channel
224 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
225 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
230 unsigned int block_length; ///< number of samples within the block
231 unsigned int ra_block; ///< if true, this is a random access block
232 int *const_block; ///< if true, this is a constant value block
233 int js_blocks; ///< true if this block contains a difference signal
234 unsigned int *shift_lsbs; ///< shift of values for this block
235 unsigned int *opt_order; ///< prediction order of this block
236 int *store_prev_samples;///< if true, carryover samples have to be stored
237 int *use_ltp; ///< if true, long-term prediction is used
238 int *ltp_lag; ///< lag value for long-term prediction
239 int *ltp_gain; ///< gain values for ltp 5-tap filter
240 int32_t *quant_cof; ///< quantized parcor coefficients
241 int32_t *lpc_cof; ///< coefficients of the direct form prediction
242 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
243 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
244 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
248 static av_cold void dprint_specific_config(ALSDecContext *ctx)
251 AVCodecContext *avctx = ctx->avctx;
252 ALSSpecificConfig *sconf = &ctx->sconf;
254 av_dlog(avctx, "resolution = %i\n", sconf->resolution);
255 av_dlog(avctx, "floating = %i\n", sconf->floating);
256 av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
257 av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
258 av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
259 av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
260 av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
261 av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
262 av_dlog(avctx, "max_order = %i\n", sconf->max_order);
263 av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
264 av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
265 av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
266 av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
267 av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
268 av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
269 av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
270 av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
271 av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
276 /** Read an ALSSpecificConfig from a buffer into the output struct.
278 static av_cold int read_specific_config(ALSDecContext *ctx)
282 int i, config_offset;
283 MPEG4AudioConfig m4ac;
284 ALSSpecificConfig *sconf = &ctx->sconf;
285 AVCodecContext *avctx = ctx->avctx;
286 uint32_t als_id, header_size, trailer_size;
289 if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0)
292 config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
293 avctx->extradata_size * 8, 1);
295 if (config_offset < 0)
298 skip_bits_long(&gb, config_offset);
300 if (get_bits_left(&gb) < (30 << 3))
303 // read the fixed items
304 als_id = get_bits_long(&gb, 32);
305 avctx->sample_rate = m4ac.sample_rate;
306 skip_bits_long(&gb, 32); // sample rate already known
307 sconf->samples = get_bits_long(&gb, 32);
308 avctx->channels = m4ac.channels;
309 skip_bits(&gb, 16); // number of channels already known
310 skip_bits(&gb, 3); // skip file_type
311 sconf->resolution = get_bits(&gb, 3);
312 sconf->floating = get_bits1(&gb);
313 sconf->msb_first = get_bits1(&gb);
314 sconf->frame_length = get_bits(&gb, 16) + 1;
315 sconf->ra_distance = get_bits(&gb, 8);
316 sconf->ra_flag = get_bits(&gb, 2);
317 sconf->adapt_order = get_bits1(&gb);
318 sconf->coef_table = get_bits(&gb, 2);
319 sconf->long_term_prediction = get_bits1(&gb);
320 sconf->max_order = get_bits(&gb, 10);
321 sconf->block_switching = get_bits(&gb, 2);
322 sconf->bgmc = get_bits1(&gb);
323 sconf->sb_part = get_bits1(&gb);
324 sconf->joint_stereo = get_bits1(&gb);
325 sconf->mc_coding = get_bits1(&gb);
326 sconf->chan_config = get_bits1(&gb);
327 sconf->chan_sort = get_bits1(&gb);
328 sconf->crc_enabled = get_bits1(&gb);
329 sconf->rlslms = get_bits1(&gb);
330 skip_bits(&gb, 5); // skip 5 reserved bits
331 skip_bits1(&gb); // skip aux_data_enabled
334 // check for ALSSpecificConfig struct
335 if (als_id != MKBETAG('A','L','S','\0'))
338 ctx->cur_frame_length = sconf->frame_length;
340 // read channel config
341 if (sconf->chan_config)
342 sconf->chan_config_info = get_bits(&gb, 16);
343 // TODO: use this to set avctx->channel_layout
346 // read channel sorting
347 if (sconf->chan_sort && avctx->channels > 1) {
348 int chan_pos_bits = av_ceil_log2(avctx->channels);
349 int bits_needed = avctx->channels * chan_pos_bits + 7;
350 if (get_bits_left(&gb) < bits_needed)
353 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
354 return AVERROR(ENOMEM);
358 for (i = 0; i < avctx->channels; i++) {
361 idx = get_bits(&gb, chan_pos_bits);
362 if (idx >= avctx->channels) {
363 av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n");
367 sconf->chan_pos[idx] = i;
374 // read fixed header and trailer sizes,
375 // if size = 0xFFFFFFFF then there is no data field!
376 if (get_bits_left(&gb) < 64)
379 header_size = get_bits_long(&gb, 32);
380 trailer_size = get_bits_long(&gb, 32);
381 if (header_size == 0xFFFFFFFF)
383 if (trailer_size == 0xFFFFFFFF)
386 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
389 // skip the header and trailer data
390 if (get_bits_left(&gb) < ht_size)
393 if (ht_size > INT32_MAX)
396 skip_bits_long(&gb, ht_size);
399 // initialize CRC calculation
400 if (sconf->crc_enabled) {
401 if (get_bits_left(&gb) < 32)
404 if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
405 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
406 ctx->crc = 0xFFFFFFFF;
407 ctx->crc_org = ~get_bits_long(&gb, 32);
409 skip_bits_long(&gb, 32);
413 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
415 dprint_specific_config(ctx);
421 /** Check the ALSSpecificConfig for unsupported features.
423 static int check_specific_config(ALSDecContext *ctx)
425 ALSSpecificConfig *sconf = &ctx->sconf;
428 // report unsupported feature and set error value
429 #define MISSING_ERR(cond, str, errval) \
432 avpriv_report_missing_feature(ctx->avctx, \
438 MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
439 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
445 /** Parse the bs_info field to extract the block partitioning used in
446 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
448 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
449 unsigned int div, unsigned int **div_blocks,
450 unsigned int *num_blocks)
452 if (n < 31 && ((bs_info << n) & 0x40000000)) {
453 // if the level is valid and the investigated bit n is set
454 // then recursively check both children at bits (2n+1) and (2n+2)
457 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
458 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
460 // else the bit is not set or the last level has been reached
461 // (bit implicitly not set)
469 /** Read and decode a Rice codeword.
471 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
473 int max = get_bits_left(gb) - k;
474 int q = get_unary(gb, 0, max);
475 int r = k ? get_bits1(gb) : !(q & 1);
479 q += get_bits_long(gb, k - 1);
487 /** Convert PARCOR coefficient k to direct filter coefficient.
489 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
493 for (i = 0, j = k - 1; i < j; i++, j--) {
494 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
495 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
499 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
505 /** Read block switching field if necessary and set actual block sizes.
506 * Also assure that the block sizes of the last frame correspond to the
507 * actual number of samples.
509 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
512 ALSSpecificConfig *sconf = &ctx->sconf;
513 GetBitContext *gb = &ctx->gb;
514 unsigned int *ptr_div_blocks = div_blocks;
517 if (sconf->block_switching) {
518 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
519 *bs_info = get_bits_long(gb, bs_info_len);
520 *bs_info <<= (32 - bs_info_len);
524 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
526 // The last frame may have an overdetermined block structure given in
527 // the bitstream. In that case the defined block structure would need
528 // more samples than available to be consistent.
529 // The block structure is actually used but the block sizes are adapted
530 // to fit the actual number of available samples.
531 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
532 // This results in the actual block sizes: 2 2 1 0.
533 // This is not specified in 14496-3 but actually done by the reference
534 // codec RM22 revision 2.
535 // This appears to happen in case of an odd number of samples in the last
536 // frame which is actually not allowed by the block length switching part
538 // The ALS conformance files feature an odd number of samples in the last
541 for (b = 0; b < ctx->num_blocks; b++)
542 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
544 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
545 unsigned int remaining = ctx->cur_frame_length;
547 for (b = 0; b < ctx->num_blocks; b++) {
548 if (remaining <= div_blocks[b]) {
549 div_blocks[b] = remaining;
550 ctx->num_blocks = b + 1;
554 remaining -= div_blocks[b];
560 /** Read the block data for a constant block
562 static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
564 ALSSpecificConfig *sconf = &ctx->sconf;
565 AVCodecContext *avctx = ctx->avctx;
566 GetBitContext *gb = &ctx->gb;
568 if (bd->block_length <= 0)
569 return AVERROR_INVALIDDATA;
571 *bd->raw_samples = 0;
572 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
573 bd->js_blocks = get_bits1(gb);
575 // skip 5 reserved bits
578 if (*bd->const_block) {
579 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
580 *bd->raw_samples = get_sbits_long(gb, const_val_bits);
583 // ensure constant block decoding by reusing this field
584 *bd->const_block = 1;
590 /** Decode the block data for a constant block
592 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
594 int smp = bd->block_length - 1;
595 int32_t val = *bd->raw_samples;
596 int32_t *dst = bd->raw_samples + 1;
598 // write raw samples into buffer
604 /** Read the block data for a non-constant block
606 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
608 ALSSpecificConfig *sconf = &ctx->sconf;
609 AVCodecContext *avctx = ctx->avctx;
610 GetBitContext *gb = &ctx->gb;
614 unsigned int sub_blocks, log2_sub_blocks, sb_length;
615 unsigned int start = 0;
616 unsigned int opt_order;
618 int32_t *quant_cof = bd->quant_cof;
619 int32_t *current_res;
622 // ensure variable block decoding by reusing this field
623 *bd->const_block = 0;
626 bd->js_blocks = get_bits1(gb);
628 opt_order = *bd->opt_order;
630 // determine the number of subblocks for entropy decoding
631 if (!sconf->bgmc && !sconf->sb_part) {
634 if (sconf->bgmc && sconf->sb_part)
635 log2_sub_blocks = get_bits(gb, 2);
637 log2_sub_blocks = 2 * get_bits1(gb);
640 sub_blocks = 1 << log2_sub_blocks;
642 // do not continue in case of a damaged stream since
643 // block_length must be evenly divisible by sub_blocks
644 if (bd->block_length & (sub_blocks - 1)) {
645 av_log(avctx, AV_LOG_WARNING,
646 "Block length is not evenly divisible by the number of subblocks.\n");
650 sb_length = bd->block_length >> log2_sub_blocks;
653 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
654 for (k = 1; k < sub_blocks; k++)
655 s[k] = s[k - 1] + decode_rice(gb, 2);
657 for (k = 0; k < sub_blocks; k++) {
662 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
663 for (k = 1; k < sub_blocks; k++)
664 s[k] = s[k - 1] + decode_rice(gb, 0);
666 for (k = 1; k < sub_blocks; k++)
668 av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
669 return AVERROR_INVALIDDATA;
673 *bd->shift_lsbs = get_bits(gb, 4) + 1;
675 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
678 if (!sconf->rlslms) {
679 if (sconf->adapt_order) {
680 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
681 2, sconf->max_order + 1));
682 *bd->opt_order = get_bits(gb, opt_order_length);
683 if (*bd->opt_order > sconf->max_order) {
684 *bd->opt_order = sconf->max_order;
685 av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
686 return AVERROR_INVALIDDATA;
689 *bd->opt_order = sconf->max_order;
692 opt_order = *bd->opt_order;
697 if (sconf->coef_table == 3) {
700 // read coefficient 0
701 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
703 // read coefficient 1
705 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
707 // read coefficients 2 to opt_order
708 for (k = 2; k < opt_order; k++)
709 quant_cof[k] = get_bits(gb, 7);
714 // read coefficient 0 to 19
715 k_max = FFMIN(opt_order, 20);
716 for (k = 0; k < k_max; k++) {
717 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
718 int offset = parcor_rice_table[sconf->coef_table][k][0];
719 quant_cof[k] = decode_rice(gb, rice_param) + offset;
720 if (quant_cof[k] < -64 || quant_cof[k] > 63) {
721 av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range.\n", quant_cof[k]);
722 return AVERROR_INVALIDDATA;
726 // read coefficients 20 to 126
727 k_max = FFMIN(opt_order, 127);
728 for (; k < k_max; k++)
729 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
731 // read coefficients 127 to opt_order
732 for (; k < opt_order; k++)
733 quant_cof[k] = decode_rice(gb, 1);
735 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
738 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
741 for (k = 2; k < opt_order; k++)
742 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
746 // read LTP gain and lag values
747 if (sconf->long_term_prediction) {
748 *bd->use_ltp = get_bits1(gb);
753 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
754 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
756 r = get_unary(gb, 0, 3);
758 bd->ltp_gain[2] = ltp_gain_values[r][c];
760 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
761 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
763 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
764 *bd->ltp_lag += FFMAX(4, opt_order + 1);
768 // read first value and residuals in case of a random access block
771 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
773 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
775 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
777 start = FFMIN(opt_order, 3);
780 // read all residuals
784 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
786 // read most significant bits
791 ff_bgmc_decode_init(gb, &high, &low, &value);
793 current_res = bd->raw_samples + start;
795 for (sb = 0; sb < sub_blocks; sb++) {
796 unsigned int sb_len = sb_length - (sb ? 0 : start);
798 k [sb] = s[sb] > b ? s[sb] - b : 0;
799 delta[sb] = 5 - s[sb] + k[sb];
801 ff_bgmc_decode(gb, sb_len, current_res,
802 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
804 current_res += sb_len;
807 ff_bgmc_decode_end(gb);
810 // read least significant bits and tails
811 current_res = bd->raw_samples + start;
813 for (sb = 0; sb < sub_blocks; sb++, start = 0) {
814 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
815 unsigned int cur_k = k[sb];
816 unsigned int cur_s = s[sb];
818 for (; start < sb_length; start++) {
819 int32_t res = *current_res;
821 if (res == cur_tail_code) {
822 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
825 res = decode_rice(gb, cur_s);
828 res += (max_msb ) << cur_k;
830 res -= (max_msb - 1) << cur_k;
833 if (res > cur_tail_code)
843 res |= get_bits_long(gb, cur_k);
847 *current_res++ = res;
851 current_res = bd->raw_samples + start;
853 for (sb = 0; sb < sub_blocks; sb++, start = 0)
854 for (; start < sb_length; start++)
855 *current_res++ = decode_rice(gb, s[sb]);
858 if (!sconf->mc_coding || ctx->js_switch)
865 /** Decode the block data for a non-constant block
867 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
869 ALSSpecificConfig *sconf = &ctx->sconf;
870 unsigned int block_length = bd->block_length;
871 unsigned int smp = 0;
873 int opt_order = *bd->opt_order;
876 int32_t *quant_cof = bd->quant_cof;
877 int32_t *lpc_cof = bd->lpc_cof;
878 int32_t *raw_samples = bd->raw_samples;
879 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
880 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
882 // reverse long-term prediction
886 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
887 int center = ltp_smp - *bd->ltp_lag;
888 int begin = FFMAX(0, center - 2);
889 int end = center + 3;
890 int tab = 5 - (end - begin);
895 for (base = begin; base < end; base++, tab++)
896 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
898 raw_samples[ltp_smp] += y >> 7;
902 // reconstruct all samples from residuals
904 for (smp = 0; smp < opt_order; smp++) {
907 for (sb = 0; sb < smp; sb++)
908 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
910 *raw_samples++ -= y >> 20;
911 parcor_to_lpc(smp, quant_cof, lpc_cof);
914 for (k = 0; k < opt_order; k++)
915 parcor_to_lpc(k, quant_cof, lpc_cof);
917 // store previous samples in case that they have to be altered
918 if (*bd->store_prev_samples)
919 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
920 sizeof(*bd->prev_raw_samples) * sconf->max_order);
922 // reconstruct difference signal for prediction (joint-stereo)
923 if (bd->js_blocks && bd->raw_other) {
924 int32_t *left, *right;
926 if (bd->raw_other > raw_samples) { // D = R - L
928 right = bd->raw_other;
929 } else { // D = R - L
930 left = bd->raw_other;
934 for (sb = -1; sb >= -sconf->max_order; sb--)
935 raw_samples[sb] = right[sb] - left[sb];
938 // reconstruct shifted signal
940 for (sb = -1; sb >= -sconf->max_order; sb--)
941 raw_samples[sb] >>= *bd->shift_lsbs;
944 // reverse linear prediction coefficients for efficiency
945 lpc_cof = lpc_cof + opt_order;
947 for (sb = 0; sb < opt_order; sb++)
948 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
950 // reconstruct raw samples
951 raw_samples = bd->raw_samples + smp;
952 lpc_cof = lpc_cof_reversed + opt_order;
954 for (; raw_samples < raw_samples_end; raw_samples++) {
957 for (sb = -opt_order; sb < 0; sb++)
958 y += MUL64(lpc_cof[sb], raw_samples[sb]);
960 *raw_samples -= y >> 20;
963 raw_samples = bd->raw_samples;
965 // restore previous samples in case that they have been altered
966 if (*bd->store_prev_samples)
967 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
968 sizeof(*raw_samples) * sconf->max_order);
974 /** Read the block data.
976 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
978 GetBitContext *gb = &ctx->gb;
982 // read block type flag and read the samples accordingly
984 if ((ret = read_var_block_data(ctx, bd)) < 0)
987 if ((ret = read_const_block_data(ctx, bd)) < 0)
995 /** Decode the block data.
997 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1001 // read block type flag and read the samples accordingly
1002 if (*bd->const_block)
1003 decode_const_block_data(ctx, bd);
1004 else if (decode_var_block_data(ctx, bd))
1007 // TODO: read RLSLMS extension data
1009 if (*bd->shift_lsbs)
1010 for (smp = 0; smp < bd->block_length; smp++)
1011 bd->raw_samples[smp] <<= *bd->shift_lsbs;
1017 /** Read and decode block data successively.
1019 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1023 ret = read_block(ctx, bd);
1028 ret = decode_block(ctx, bd);
1034 /** Compute the number of samples left to decode for the current frame and
1035 * sets these samples to zero.
1037 static void zero_remaining(unsigned int b, unsigned int b_max,
1038 const unsigned int *div_blocks, int32_t *buf)
1040 unsigned int count = 0;
1043 count += div_blocks[b++];
1046 memset(buf, 0, sizeof(*buf) * count);
1050 /** Decode blocks independently.
1052 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1053 unsigned int c, const unsigned int *div_blocks,
1054 unsigned int *js_blocks)
1057 ALSBlockData bd = { 0 };
1059 bd.ra_block = ra_frame;
1060 bd.const_block = ctx->const_block;
1061 bd.shift_lsbs = ctx->shift_lsbs;
1062 bd.opt_order = ctx->opt_order;
1063 bd.store_prev_samples = ctx->store_prev_samples;
1064 bd.use_ltp = ctx->use_ltp;
1065 bd.ltp_lag = ctx->ltp_lag;
1066 bd.ltp_gain = ctx->ltp_gain[0];
1067 bd.quant_cof = ctx->quant_cof[0];
1068 bd.lpc_cof = ctx->lpc_cof[0];
1069 bd.prev_raw_samples = ctx->prev_raw_samples;
1070 bd.raw_samples = ctx->raw_samples[c];
1073 for (b = 0; b < ctx->num_blocks; b++) {
1074 bd.block_length = div_blocks[b];
1076 if (read_decode_block(ctx, &bd)) {
1077 // damaged block, write zero for the rest of the frame
1078 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1081 bd.raw_samples += div_blocks[b];
1089 /** Decode blocks dependently.
1091 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1092 unsigned int c, const unsigned int *div_blocks,
1093 unsigned int *js_blocks)
1095 ALSSpecificConfig *sconf = &ctx->sconf;
1096 unsigned int offset = 0;
1098 ALSBlockData bd[2] = { { 0 } };
1100 bd[0].ra_block = ra_frame;
1101 bd[0].const_block = ctx->const_block;
1102 bd[0].shift_lsbs = ctx->shift_lsbs;
1103 bd[0].opt_order = ctx->opt_order;
1104 bd[0].store_prev_samples = ctx->store_prev_samples;
1105 bd[0].use_ltp = ctx->use_ltp;
1106 bd[0].ltp_lag = ctx->ltp_lag;
1107 bd[0].ltp_gain = ctx->ltp_gain[0];
1108 bd[0].quant_cof = ctx->quant_cof[0];
1109 bd[0].lpc_cof = ctx->lpc_cof[0];
1110 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1111 bd[0].js_blocks = *js_blocks;
1113 bd[1].ra_block = ra_frame;
1114 bd[1].const_block = ctx->const_block;
1115 bd[1].shift_lsbs = ctx->shift_lsbs;
1116 bd[1].opt_order = ctx->opt_order;
1117 bd[1].store_prev_samples = ctx->store_prev_samples;
1118 bd[1].use_ltp = ctx->use_ltp;
1119 bd[1].ltp_lag = ctx->ltp_lag;
1120 bd[1].ltp_gain = ctx->ltp_gain[0];
1121 bd[1].quant_cof = ctx->quant_cof[0];
1122 bd[1].lpc_cof = ctx->lpc_cof[0];
1123 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1124 bd[1].js_blocks = *(js_blocks + 1);
1126 // decode all blocks
1127 for (b = 0; b < ctx->num_blocks; b++) {
1130 bd[0].block_length = div_blocks[b];
1131 bd[1].block_length = div_blocks[b];
1133 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1134 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1136 bd[0].raw_other = bd[1].raw_samples;
1137 bd[1].raw_other = bd[0].raw_samples;
1139 if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1140 // damaged block, write zero for the rest of the frame
1141 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1142 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1146 // reconstruct joint-stereo blocks
1147 if (bd[0].js_blocks) {
1148 if (bd[1].js_blocks)
1149 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1151 for (s = 0; s < div_blocks[b]; s++)
1152 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1153 } else if (bd[1].js_blocks) {
1154 for (s = 0; s < div_blocks[b]; s++)
1155 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1158 offset += div_blocks[b];
1163 // store carryover raw samples,
1164 // the others channel raw samples are stored by the calling function.
1165 memmove(ctx->raw_samples[c] - sconf->max_order,
1166 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1167 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1173 /** Read the channel data.
1175 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1177 GetBitContext *gb = &ctx->gb;
1178 ALSChannelData *current = cd;
1179 unsigned int channels = ctx->avctx->channels;
1182 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1183 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1185 if (current->master_channel >= channels) {
1186 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n");
1190 if (current->master_channel != c) {
1191 current->time_diff_flag = get_bits1(gb);
1192 current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1193 current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 31)];
1194 current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1196 if (current->time_diff_flag) {
1197 current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1198 current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1199 current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)];
1201 current->time_diff_sign = get_bits1(gb);
1202 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1210 if (entries == channels) {
1211 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n");
1220 /** Recursively reverts the inter-channel correlation for a block.
1222 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1223 ALSChannelData **cd, int *reverted,
1224 unsigned int offset, int c)
1226 ALSChannelData *ch = cd[c];
1227 unsigned int dep = 0;
1228 unsigned int channels = ctx->avctx->channels;
1235 while (dep < channels && !ch[dep].stop_flag) {
1236 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1237 ch[dep].master_channel);
1242 if (dep == channels) {
1243 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1247 bd->const_block = ctx->const_block + c;
1248 bd->shift_lsbs = ctx->shift_lsbs + c;
1249 bd->opt_order = ctx->opt_order + c;
1250 bd->store_prev_samples = ctx->store_prev_samples + c;
1251 bd->use_ltp = ctx->use_ltp + c;
1252 bd->ltp_lag = ctx->ltp_lag + c;
1253 bd->ltp_gain = ctx->ltp_gain[c];
1254 bd->lpc_cof = ctx->lpc_cof[c];
1255 bd->quant_cof = ctx->quant_cof[c];
1256 bd->raw_samples = ctx->raw_samples[c] + offset;
1259 while (!ch[dep].stop_flag) {
1261 unsigned int begin = 1;
1262 unsigned int end = bd->block_length - 1;
1264 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1266 if (ch[dep].time_diff_flag) {
1267 int t = ch[dep].time_diff_index;
1269 if (ch[dep].time_diff_sign) {
1276 for (smp = begin; smp < end; smp++) {
1278 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1279 MUL64(ch[dep].weighting[1], master[smp ]) +
1280 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1281 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1282 MUL64(ch[dep].weighting[4], master[smp + t]) +
1283 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1285 bd->raw_samples[smp] += y >> 7;
1288 for (smp = begin; smp < end; smp++) {
1290 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1291 MUL64(ch[dep].weighting[1], master[smp ]) +
1292 MUL64(ch[dep].weighting[2], master[smp + 1]);
1294 bd->raw_samples[smp] += y >> 7;
1305 /** Read the frame data.
1307 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1309 ALSSpecificConfig *sconf = &ctx->sconf;
1310 AVCodecContext *avctx = ctx->avctx;
1311 GetBitContext *gb = &ctx->gb;
1312 unsigned int div_blocks[32]; ///< block sizes.
1314 unsigned int js_blocks[2];
1316 uint32_t bs_info = 0;
1318 // skip the size of the ra unit if present in the frame
1319 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1320 skip_bits_long(gb, 32);
1322 if (sconf->mc_coding && sconf->joint_stereo) {
1323 ctx->js_switch = get_bits1(gb);
1327 if (!sconf->mc_coding || ctx->js_switch) {
1328 int independent_bs = !sconf->joint_stereo;
1330 for (c = 0; c < avctx->channels; c++) {
1334 get_block_sizes(ctx, div_blocks, &bs_info);
1336 // if joint_stereo and block_switching is set, independent decoding
1337 // is signaled via the first bit of bs_info
1338 if (sconf->joint_stereo && sconf->block_switching)
1342 // if this is the last channel, it has to be decoded independently
1343 if (c == avctx->channels - 1)
1346 if (independent_bs) {
1347 if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1352 if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1358 // store carryover raw samples
1359 memmove(ctx->raw_samples[c] - sconf->max_order,
1360 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1361 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1363 } else { // multi-channel coding
1364 ALSBlockData bd = { 0 };
1366 int *reverted_channels = ctx->reverted_channels;
1367 unsigned int offset = 0;
1369 for (c = 0; c < avctx->channels; c++)
1370 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1371 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n");
1375 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1377 bd.ra_block = ra_frame;
1378 bd.prev_raw_samples = ctx->prev_raw_samples;
1380 get_block_sizes(ctx, div_blocks, &bs_info);
1382 for (b = 0; b < ctx->num_blocks; b++) {
1383 bd.block_length = div_blocks[b];
1385 for (c = 0; c < avctx->channels; c++) {
1386 bd.const_block = ctx->const_block + c;
1387 bd.shift_lsbs = ctx->shift_lsbs + c;
1388 bd.opt_order = ctx->opt_order + c;
1389 bd.store_prev_samples = ctx->store_prev_samples + c;
1390 bd.use_ltp = ctx->use_ltp + c;
1391 bd.ltp_lag = ctx->ltp_lag + c;
1392 bd.ltp_gain = ctx->ltp_gain[c];
1393 bd.lpc_cof = ctx->lpc_cof[c];
1394 bd.quant_cof = ctx->quant_cof[c];
1395 bd.raw_samples = ctx->raw_samples[c] + offset;
1396 bd.raw_other = NULL;
1398 if ((ret = read_block(ctx, &bd)) < 0)
1400 if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1404 for (c = 0; c < avctx->channels; c++)
1405 if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1406 reverted_channels, offset, c))
1409 for (c = 0; c < avctx->channels; c++) {
1410 bd.const_block = ctx->const_block + c;
1411 bd.shift_lsbs = ctx->shift_lsbs + c;
1412 bd.opt_order = ctx->opt_order + c;
1413 bd.store_prev_samples = ctx->store_prev_samples + c;
1414 bd.use_ltp = ctx->use_ltp + c;
1415 bd.ltp_lag = ctx->ltp_lag + c;
1416 bd.ltp_gain = ctx->ltp_gain[c];
1417 bd.lpc_cof = ctx->lpc_cof[c];
1418 bd.quant_cof = ctx->quant_cof[c];
1419 bd.raw_samples = ctx->raw_samples[c] + offset;
1421 if ((ret = decode_block(ctx, &bd)) < 0)
1425 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1426 offset += div_blocks[b];
1430 // store carryover raw samples
1431 for (c = 0; c < avctx->channels; c++)
1432 memmove(ctx->raw_samples[c] - sconf->max_order,
1433 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1434 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1437 // TODO: read_diff_float_data
1443 /** Decode an ALS frame.
1445 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1448 ALSDecContext *ctx = avctx->priv_data;
1449 AVFrame *frame = data;
1450 ALSSpecificConfig *sconf = &ctx->sconf;
1451 const uint8_t *buffer = avpkt->data;
1452 int buffer_size = avpkt->size;
1453 int invalid_frame, ret;
1454 unsigned int c, sample, ra_frame, bytes_read, shift;
1456 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1458 // In the case that the distance between random access frames is set to zero
1459 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1460 // For the first frame, if prediction is used, all samples used from the
1461 // previous frame are assumed to be zero.
1462 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1464 // the last frame to decode might have a different length
1465 if (sconf->samples != 0xFFFFFFFF)
1466 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1467 sconf->frame_length);
1469 ctx->cur_frame_length = sconf->frame_length;
1471 // decode the frame data
1472 if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1473 av_log(ctx->avctx, AV_LOG_WARNING,
1474 "Reading frame data failed. Skipping RA unit.\n");
1478 /* get output buffer */
1479 frame->nb_samples = ctx->cur_frame_length;
1480 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1483 // transform decoded frame into output format
1484 #define INTERLEAVE_OUTPUT(bps) \
1486 int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1487 shift = bps - ctx->avctx->bits_per_raw_sample; \
1488 if (!ctx->cs_switch) { \
1489 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1490 for (c = 0; c < avctx->channels; c++) \
1491 *dest++ = ctx->raw_samples[c][sample] << shift; \
1493 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1494 for (c = 0; c < avctx->channels; c++) \
1495 *dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] << shift; \
1499 if (ctx->avctx->bits_per_raw_sample <= 16) {
1500 INTERLEAVE_OUTPUT(16)
1502 INTERLEAVE_OUTPUT(32)
1506 if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1507 int swap = HAVE_BIGENDIAN != sconf->msb_first;
1509 if (ctx->avctx->bits_per_raw_sample == 24) {
1510 int32_t *src = (int32_t *)frame->data[0];
1513 sample < ctx->cur_frame_length * avctx->channels;
1518 v = av_bswap32(src[sample]);
1521 if (!HAVE_BIGENDIAN)
1524 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1527 uint8_t *crc_source;
1530 if (ctx->avctx->bits_per_raw_sample <= 16) {
1531 int16_t *src = (int16_t*) frame->data[0];
1532 int16_t *dest = (int16_t*) ctx->crc_buffer;
1534 sample < ctx->cur_frame_length * avctx->channels;
1536 *dest++ = av_bswap16(src[sample]);
1538 ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1539 (uint32_t *)frame->data[0],
1540 ctx->cur_frame_length * avctx->channels);
1542 crc_source = ctx->crc_buffer;
1544 crc_source = frame->data[0];
1547 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1548 ctx->cur_frame_length * avctx->channels *
1549 av_get_bytes_per_sample(avctx->sample_fmt));
1553 // check CRC sums if this is the last frame
1554 if (ctx->cur_frame_length != sconf->frame_length &&
1555 ctx->crc_org != ctx->crc) {
1556 av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1562 bytes_read = invalid_frame ? buffer_size :
1563 (get_bits_count(&ctx->gb) + 7) >> 3;
1569 /** Uninitialize the ALS decoder.
1571 static av_cold int decode_end(AVCodecContext *avctx)
1573 ALSDecContext *ctx = avctx->priv_data;
1575 av_freep(&ctx->sconf.chan_pos);
1577 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1579 av_freep(&ctx->const_block);
1580 av_freep(&ctx->shift_lsbs);
1581 av_freep(&ctx->opt_order);
1582 av_freep(&ctx->store_prev_samples);
1583 av_freep(&ctx->use_ltp);
1584 av_freep(&ctx->ltp_lag);
1585 av_freep(&ctx->ltp_gain);
1586 av_freep(&ctx->ltp_gain_buffer);
1587 av_freep(&ctx->quant_cof);
1588 av_freep(&ctx->lpc_cof);
1589 av_freep(&ctx->quant_cof_buffer);
1590 av_freep(&ctx->lpc_cof_buffer);
1591 av_freep(&ctx->lpc_cof_reversed_buffer);
1592 av_freep(&ctx->prev_raw_samples);
1593 av_freep(&ctx->raw_samples);
1594 av_freep(&ctx->raw_buffer);
1595 av_freep(&ctx->chan_data);
1596 av_freep(&ctx->chan_data_buffer);
1597 av_freep(&ctx->reverted_channels);
1598 av_freep(&ctx->crc_buffer);
1604 /** Initialize the ALS decoder.
1606 static av_cold int decode_init(AVCodecContext *avctx)
1609 unsigned int channel_size;
1611 ALSDecContext *ctx = avctx->priv_data;
1612 ALSSpecificConfig *sconf = &ctx->sconf;
1615 if (!avctx->extradata) {
1616 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1620 if (read_specific_config(ctx)) {
1621 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1626 if (check_specific_config(ctx)) {
1632 ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1634 if (sconf->floating) {
1635 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1636 avctx->bits_per_raw_sample = 32;
1638 avctx->sample_fmt = sconf->resolution > 1
1639 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1640 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1643 // set maximum Rice parameter for progressive decoding based on resolution
1644 // This is not specified in 14496-3 but actually done by the reference
1645 // codec RM22 revision 2.
1646 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1648 // set lag value for long-term prediction
1649 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1650 (avctx->sample_rate >= 192000);
1652 // allocate quantized parcor coefficient buffer
1653 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1655 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1656 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1657 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1658 num_buffers * sconf->max_order);
1659 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1660 num_buffers * sconf->max_order);
1661 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1664 if (!ctx->quant_cof || !ctx->lpc_cof ||
1665 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1666 !ctx->lpc_cof_reversed_buffer) {
1667 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1668 return AVERROR(ENOMEM);
1671 // assign quantized parcor coefficient buffers
1672 for (c = 0; c < num_buffers; c++) {
1673 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1674 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1677 // allocate and assign lag and gain data buffer for ltp mode
1678 ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1679 ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1680 ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1681 ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1682 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1683 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1684 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1685 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1688 if (!ctx->const_block || !ctx->shift_lsbs ||
1689 !ctx->opt_order || !ctx->store_prev_samples ||
1690 !ctx->use_ltp || !ctx->ltp_lag ||
1691 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1692 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1694 return AVERROR(ENOMEM);
1697 for (c = 0; c < num_buffers; c++)
1698 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1700 // allocate and assign channel data buffer for mcc mode
1701 if (sconf->mc_coding) {
1702 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1703 num_buffers * num_buffers);
1704 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1706 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1709 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1710 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1712 return AVERROR(ENOMEM);
1715 for (c = 0; c < num_buffers; c++)
1716 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1718 ctx->chan_data = NULL;
1719 ctx->chan_data_buffer = NULL;
1720 ctx->reverted_channels = NULL;
1723 channel_size = sconf->frame_length + sconf->max_order;
1725 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1726 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1727 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1729 // allocate previous raw sample buffer
1730 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1731 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1733 return AVERROR(ENOMEM);
1736 // assign raw samples buffers
1737 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1738 for (c = 1; c < avctx->channels; c++)
1739 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1741 // allocate crc buffer
1742 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1743 (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1744 ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1745 ctx->cur_frame_length *
1747 av_get_bytes_per_sample(avctx->sample_fmt));
1748 if (!ctx->crc_buffer) {
1749 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1751 return AVERROR(ENOMEM);
1755 ff_dsputil_init(&ctx->dsp, avctx);
1761 /** Flush (reset) the frame ID after seeking.
1763 static av_cold void flush(AVCodecContext *avctx)
1765 ALSDecContext *ctx = avctx->priv_data;
1771 AVCodec ff_als_decoder = {
1773 .type = AVMEDIA_TYPE_AUDIO,
1774 .id = AV_CODEC_ID_MP4ALS,
1775 .priv_data_size = sizeof(ALSDecContext),
1776 .init = decode_init,
1777 .close = decode_end,
1778 .decode = decode_frame,
1780 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1781 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),