1/* 2 * MPEG-4 ALS decoder 3 * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ mail.de> 4 * 5 * This file is part of FFmpeg. 6 * 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. 11 * 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. 16 * 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 20 */ 21 22/** 23 * @file 24 * MPEG-4 ALS decoder 25 * @author Thilo Borgmann <thilo.borgmann _at_ mail.de> 26 */ 27 28#include <inttypes.h> 29 30#include "avcodec.h" 31#include "get_bits.h" 32#include "unary.h" 33#include "mpeg4audio.h" 34#include "bytestream.h" 35#include "bgmc.h" 36#include "bswapdsp.h" 37#include "internal.h" 38#include "libavutil/samplefmt.h" 39#include "libavutil/crc.h" 40 41#include <stdint.h> 42 43/** Rice parameters and corresponding index offsets for decoding the 44 * indices of scaled PARCOR values. The table chosen is set globally 45 * by the encoder and stored in ALSSpecificConfig. 46 */ 47static const int8_t parcor_rice_table[3][20][2] = { 48 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4}, 49 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3}, 50 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2}, 51 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} }, 52 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4}, 53 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4}, 54 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4}, 55 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} }, 56 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4}, 57 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3}, 58 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3}, 59 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} } 60}; 61 62 63/** Scaled PARCOR values used for the first two PARCOR coefficients. 64 * To be indexed by the Rice coded indices. 65 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20) 66 * Actual values are divided by 32 in order to be stored in 16 bits. 67 */ 68static const int16_t parcor_scaled_values[] = { 69 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32, 70 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32, 71 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32, 72 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32, 73 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32, 74 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32, 75 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32, 76 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32, 77 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32, 78 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32, 79 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32, 80 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32, 81 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32, 82 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32, 83 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32, 84 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32, 85 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32, 86 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32, 87 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32, 88 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32, 89 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32, 90 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32, 91 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32, 92 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32, 93 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32, 94 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32, 95 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32, 96 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32, 97 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32, 98 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32, 99 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32, 100 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32 101}; 102 103 104/** Gain values of p(0) for long-term prediction. 105 * To be indexed by the Rice coded indices. 106 */ 107static const uint8_t ltp_gain_values [4][4] = { 108 { 0, 8, 16, 24}, 109 {32, 40, 48, 56}, 110 {64, 70, 76, 82}, 111 {88, 92, 96, 100} 112}; 113 114 115/** Inter-channel weighting factors for multi-channel correlation. 116 * To be indexed by the Rice coded indices. 117 */ 118static const int16_t mcc_weightings[] = { 119 204, 192, 179, 166, 153, 140, 128, 115, 120 102, 89, 76, 64, 51, 38, 25, 12, 121 0, -12, -25, -38, -51, -64, -76, -89, 122 -102, -115, -128, -140, -153, -166, -179, -192 123}; 124 125 126/** Tail codes used in arithmetic coding using block Gilbert-Moore codes. 127 */ 128static const uint8_t tail_code[16][6] = { 129 { 74, 44, 25, 13, 7, 3}, 130 { 68, 42, 24, 13, 7, 3}, 131 { 58, 39, 23, 13, 7, 3}, 132 {126, 70, 37, 19, 10, 5}, 133 {132, 70, 37, 20, 10, 5}, 134 {124, 70, 38, 20, 10, 5}, 135 {120, 69, 37, 20, 11, 5}, 136 {116, 67, 37, 20, 11, 5}, 137 {108, 66, 36, 20, 10, 5}, 138 {102, 62, 36, 20, 10, 5}, 139 { 88, 58, 34, 19, 10, 5}, 140 {162, 89, 49, 25, 13, 7}, 141 {156, 87, 49, 26, 14, 7}, 142 {150, 86, 47, 26, 14, 7}, 143 {142, 84, 47, 26, 14, 7}, 144 {131, 79, 46, 26, 14, 7} 145}; 146 147 148enum RA_Flag { 149 RA_FLAG_NONE, 150 RA_FLAG_FRAMES, 151 RA_FLAG_HEADER 152}; 153 154 155typedef struct { 156 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown 157 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit 158 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer 159 int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian 160 int frame_length; ///< frame length for each frame (last frame may differ) 161 int ra_distance; ///< distance between RA frames (in frames, 0...255) 162 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored 163 int adapt_order; ///< adaptive order: 1 = on, 0 = off 164 int coef_table; ///< table index of Rice code parameters 165 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off 166 int max_order; ///< maximum prediction order (0..1023) 167 int block_switching; ///< number of block switching levels 168 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only) 169 int sb_part; ///< sub-block partition 170 int joint_stereo; ///< joint stereo: 1 = on, 0 = off 171 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off 172 int chan_config; ///< indicates that a chan_config_info field is present 173 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off 174 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off 175 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented. 176 int *chan_pos; ///< original channel positions 177 int crc_enabled; ///< enable Cyclic Redundancy Checksum 178} ALSSpecificConfig; 179 180 181typedef struct { 182 int stop_flag; 183 int master_channel; 184 int time_diff_flag; 185 int time_diff_sign; 186 int time_diff_index; 187 int weighting[6]; 188} ALSChannelData; 189 190 191typedef struct { 192 AVCodecContext *avctx; 193 ALSSpecificConfig sconf; 194 GetBitContext gb; 195 BswapDSPContext bdsp; 196 const AVCRC *crc_table; 197 uint32_t crc_org; ///< CRC value of the original input data 198 uint32_t crc; ///< CRC value calculated from decoded data 199 unsigned int cur_frame_length; ///< length of the current frame to decode 200 unsigned int frame_id; ///< the frame ID / number of the current frame 201 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced 202 unsigned int cs_switch; ///< if true, channel rearrangement is done 203 unsigned int num_blocks; ///< number of blocks used in the current frame 204 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding 205 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC 206 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC 207 int ltp_lag_length; ///< number of bits used for ltp lag value 208 int *const_block; ///< contains const_block flags for all channels 209 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels 210 unsigned int *opt_order; ///< contains opt_order flags for all channels 211 int *store_prev_samples; ///< contains store_prev_samples flags for all channels 212 int *use_ltp; ///< contains use_ltp flags for all channels 213 int *ltp_lag; ///< contains ltp lag values for all channels 214 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel 215 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter 216 int32_t **quant_cof; ///< quantized parcor coefficients for a channel 217 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients 218 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel 219 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter 220 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer 221 ALSChannelData **chan_data; ///< channel data for multi-channel correlation 222 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels 223 int *reverted_channels; ///< stores a flag for each reverted channel 224 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block 225 int32_t **raw_samples; ///< decoded raw samples for each channel 226 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples 227 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check 228} ALSDecContext; 229 230 231typedef struct { 232 unsigned int block_length; ///< number of samples within the block 233 unsigned int ra_block; ///< if true, this is a random access block 234 int *const_block; ///< if true, this is a constant value block 235 int js_blocks; ///< true if this block contains a difference signal 236 unsigned int *shift_lsbs; ///< shift of values for this block 237 unsigned int *opt_order; ///< prediction order of this block 238 int *store_prev_samples;///< if true, carryover samples have to be stored 239 int *use_ltp; ///< if true, long-term prediction is used 240 int *ltp_lag; ///< lag value for long-term prediction 241 int *ltp_gain; ///< gain values for ltp 5-tap filter 242 int32_t *quant_cof; ///< quantized parcor coefficients 243 int32_t *lpc_cof; ///< coefficients of the direct form prediction 244 int32_t *raw_samples; ///< decoded raw samples / residuals for this block 245 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block 246 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair 247} ALSBlockData; 248 249 250static av_cold void dprint_specific_config(ALSDecContext *ctx) 251{ 252#ifdef DEBUG 253 AVCodecContext *avctx = ctx->avctx; 254 ALSSpecificConfig *sconf = &ctx->sconf; 255 256 av_dlog(avctx, "resolution = %i\n", sconf->resolution); 257 av_dlog(avctx, "floating = %i\n", sconf->floating); 258 av_dlog(avctx, "frame_length = %i\n", sconf->frame_length); 259 av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance); 260 av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag); 261 av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order); 262 av_dlog(avctx, "coef_table = %i\n", sconf->coef_table); 263 av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction); 264 av_dlog(avctx, "max_order = %i\n", sconf->max_order); 265 av_dlog(avctx, "block_switching = %i\n", sconf->block_switching); 266 av_dlog(avctx, "bgmc = %i\n", sconf->bgmc); 267 av_dlog(avctx, "sb_part = %i\n", sconf->sb_part); 268 av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo); 269 av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding); 270 av_dlog(avctx, "chan_config = %i\n", sconf->chan_config); 271 av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort); 272 av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms); 273 av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info); 274#endif 275} 276 277 278/** Read an ALSSpecificConfig from a buffer into the output struct. 279 */ 280static av_cold int read_specific_config(ALSDecContext *ctx) 281{ 282 GetBitContext gb; 283 uint64_t ht_size; 284 int i, config_offset; 285 MPEG4AudioConfig m4ac = {0}; 286 ALSSpecificConfig *sconf = &ctx->sconf; 287 AVCodecContext *avctx = ctx->avctx; 288 uint32_t als_id, header_size, trailer_size; 289 int ret; 290 291 if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0) 292 return ret; 293 294 config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata, 295 avctx->extradata_size * 8, 1); 296 297 if (config_offset < 0) 298 return AVERROR_INVALIDDATA; 299 300 skip_bits_long(&gb, config_offset); 301 302 if (get_bits_left(&gb) < (30 << 3)) 303 return AVERROR_INVALIDDATA; 304 305 // 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 known 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 334 335 336 // check for ALSSpecificConfig struct 337 if (als_id != MKBETAG('A','L','S','\0')) 338 return AVERROR_INVALIDDATA; 339 340 ctx->cur_frame_length = sconf->frame_length; 341 342 // 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 346 347 348 // 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) 353 return AVERROR_INVALIDDATA; 354 355 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos)))) 356 return AVERROR(ENOMEM); 357 358 ctx->cs_switch = 1; 359 360 for (i = 0; i < avctx->channels; i++) { 361 int idx; 362 363 idx = get_bits(&gb, chan_pos_bits); 364 if (idx >= avctx->channels) { 365 av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n"); 366 ctx->cs_switch = 0; 367 break; 368 } 369 sconf->chan_pos[idx] = i; 370 } 371 372 align_get_bits(&gb); 373 } 374 375 376 // read fixed header and trailer sizes, 377 // if size = 0xFFFFFFFF then there is no data field! 378 if (get_bits_left(&gb) < 64) 379 return AVERROR_INVALIDDATA; 380 381 header_size = get_bits_long(&gb, 32); 382 trailer_size = get_bits_long(&gb, 32); 383 if (header_size == 0xFFFFFFFF) 384 header_size = 0; 385 if (trailer_size == 0xFFFFFFFF) 386 trailer_size = 0; 387 388 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3; 389 390 391 // skip the header and trailer data 392 if (get_bits_left(&gb) < ht_size) 393 return AVERROR_INVALIDDATA; 394 395 if (ht_size > INT32_MAX) 396 return AVERROR_PATCHWELCOME; 397 398 skip_bits_long(&gb, ht_size); 399 400 401 // initialize CRC calculation 402 if (sconf->crc_enabled) { 403 if (get_bits_left(&gb) < 32) 404 return AVERROR_INVALIDDATA; 405 406 if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) { 407 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE); 408 ctx->crc = 0xFFFFFFFF; 409 ctx->crc_org = ~get_bits_long(&gb, 32); 410 } else 411 skip_bits_long(&gb, 32); 412 } 413 414 415 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data) 416 417 dprint_specific_config(ctx); 418 419 return 0; 420} 421 422 423/** Check the ALSSpecificConfig for unsupported features. 424 */ 425static int check_specific_config(ALSDecContext *ctx) 426{ 427 ALSSpecificConfig *sconf = &ctx->sconf; 428 int error = 0; 429 430 // report unsupported feature and set error value 431 #define MISSING_ERR(cond, str, errval) \ 432 { \ 433 if (cond) { \ 434 avpriv_report_missing_feature(ctx->avctx, \ 435 str); \ 436 error = errval; \ 437 } \ 438 } 439 440 MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME); 441 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME); 442 443 return error; 444} 445 446 447/** Parse the bs_info field to extract the block partitioning used in 448 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2. 449 */ 450static void parse_bs_info(const uint32_t bs_info, unsigned int n, 451 unsigned int div, unsigned int **div_blocks, 452 unsigned int *num_blocks) 453{ 454 if (n < 31 && ((bs_info << n) & 0x40000000)) { 455 // if the level is valid and the investigated bit n is set 456 // then recursively check both children at bits (2n+1) and (2n+2) 457 n *= 2; 458 div += 1; 459 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks); 460 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks); 461 } else { 462 // else the bit is not set or the last level has been reached 463 // (bit implicitly not set) 464 **div_blocks = div; 465 (*div_blocks)++; 466 (*num_blocks)++; 467 } 468} 469 470 471/** Read and decode a Rice codeword. 472 */ 473static int32_t decode_rice(GetBitContext *gb, unsigned int k) 474{ 475 int max = get_bits_left(gb) - k; 476 int q = get_unary(gb, 0, max); 477 int r = k ? get_bits1(gb) : !(q & 1); 478 479 if (k > 1) { 480 q <<= (k - 1); 481 q += get_bits_long(gb, k - 1); 482 } else if (!k) { 483 q >>= 1; 484 } 485 return r ? q : ~q; 486} 487 488 489/** Convert PARCOR coefficient k to direct filter coefficient. 490 */ 491static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof) 492{ 493 int i, j; 494 495 for (i = 0, j = k - 1; i < j; i++, j--) { 496 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20); 497 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20); 498 cof[i] += tmp1; 499 } 500 if (i == j) 501 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20); 502 503 cof[k] = par[k]; 504} 505 506 507/** Read block switching field if necessary and set actual block sizes. 508 * Also assure that the block sizes of the last frame correspond to the 509 * actual number of samples. 510 */ 511static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks, 512 uint32_t *bs_info) 513{ 514 ALSSpecificConfig *sconf = &ctx->sconf; 515 GetBitContext *gb = &ctx->gb; 516 unsigned int *ptr_div_blocks = div_blocks; 517 unsigned int b; 518 519 if (sconf->block_switching) { 520 unsigned int bs_info_len = 1 << (sconf->block_switching + 2); 521 *bs_info = get_bits_long(gb, bs_info_len); 522 *bs_info <<= (32 - bs_info_len); 523 } 524 525 ctx->num_blocks = 0; 526 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks); 527 528 // The last frame may have an overdetermined block structure given in 529 // the bitstream. In that case the defined block structure would need 530 // more samples than available to be consistent. 531 // The block structure is actually used but the block sizes are adapted 532 // to fit the actual number of available samples. 533 // Example: 5 samples, 2nd level block sizes: 2 2 2 2. 534 // This results in the actual block sizes: 2 2 1 0. 535 // This is not specified in 14496-3 but actually done by the reference 536 // codec RM22 revision 2. 537 // This appears to happen in case of an odd number of samples in the last 538 // frame which is actually not allowed by the block length switching part 539 // of 14496-3. 540 // The ALS conformance files feature an odd number of samples in the last 541 // frame. 542 543 for (b = 0; b < ctx->num_blocks; b++) 544 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b]; 545 546 if (ctx->cur_frame_length != ctx->sconf.frame_length) { 547 unsigned int remaining = ctx->cur_frame_length; 548 549 for (b = 0; b < ctx->num_blocks; b++) { 550 if (remaining <= div_blocks[b]) { 551 div_blocks[b] = remaining; 552 ctx->num_blocks = b + 1; 553 break; 554 } 555 556 remaining -= div_blocks[b]; 557 } 558 } 559} 560 561 562/** Read the block data for a constant block 563 */ 564static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd) 565{ 566 ALSSpecificConfig *sconf = &ctx->sconf; 567 AVCodecContext *avctx = ctx->avctx; 568 GetBitContext *gb = &ctx->gb; 569 570 if (bd->block_length <= 0) 571 return AVERROR_INVALIDDATA; 572 573 *bd->raw_samples = 0; 574 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence) 575 bd->js_blocks = get_bits1(gb); 576 577 // skip 5 reserved bits 578 skip_bits(gb, 5); 579 580 if (*bd->const_block) { 581 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample; 582 *bd->raw_samples = get_sbits_long(gb, const_val_bits); 583 } 584 585 // ensure constant block decoding by reusing this field 586 *bd->const_block = 1; 587 588 return 0; 589} 590 591 592/** Decode the block data for a constant block 593 */ 594static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd) 595{ 596 int smp = bd->block_length - 1; 597 int32_t val = *bd->raw_samples; 598 int32_t *dst = bd->raw_samples + 1; 599 600 // write raw samples into buffer 601 for (; smp; smp--) 602 *dst++ = val; 603} 604 605 606/** Read the block data for a non-constant block 607 */ 608static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd) 609{ 610 ALSSpecificConfig *sconf = &ctx->sconf; 611 AVCodecContext *avctx = ctx->avctx; 612 GetBitContext *gb = &ctx->gb; 613 unsigned int k; 614 unsigned int s[8]; 615 unsigned int sx[8]; 616 unsigned int sub_blocks, log2_sub_blocks, sb_length; 617 unsigned int start = 0; 618 unsigned int opt_order; 619 int sb; 620 int32_t *quant_cof = bd->quant_cof; 621 int32_t *current_res; 622 623 624 // ensure variable block decoding by reusing this field 625 *bd->const_block = 0; 626 627 *bd->opt_order = 1; 628 bd->js_blocks = get_bits1(gb); 629 630 opt_order = *bd->opt_order; 631 632 // determine the number of subblocks for entropy decoding 633 if (!sconf->bgmc && !sconf->sb_part) { 634 log2_sub_blocks = 0; 635 } else { 636 if (sconf->bgmc && sconf->sb_part) 637 log2_sub_blocks = get_bits(gb, 2); 638 else 639 log2_sub_blocks = 2 * get_bits1(gb); 640 } 641 642 sub_blocks = 1 << log2_sub_blocks; 643 644 // do not continue in case of a damaged stream since 645 // block_length must be evenly divisible by sub_blocks 646 if (bd->block_length & (sub_blocks - 1)) { 647 av_log(avctx, AV_LOG_WARNING, 648 "Block length is not evenly divisible by the number of subblocks.\n"); 649 return AVERROR_INVALIDDATA; 650 } 651 652 sb_length = bd->block_length >> log2_sub_blocks; 653 654 if (sconf->bgmc) { 655 s[0] = get_bits(gb, 8 + (sconf->resolution > 1)); 656 for (k = 1; k < sub_blocks; k++) 657 s[k] = s[k - 1] + decode_rice(gb, 2); 658 659 for (k = 0; k < sub_blocks; k++) { 660 sx[k] = s[k] & 0x0F; 661 s [k] >>= 4; 662 } 663 } else { 664 s[0] = get_bits(gb, 4 + (sconf->resolution > 1)); 665 for (k = 1; k < sub_blocks; k++) 666 s[k] = s[k - 1] + decode_rice(gb, 0); 667 } 668 for (k = 1; k < sub_blocks; k++) 669 if (s[k] > 32) { 670 av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n"); 671 return AVERROR_INVALIDDATA; 672 } 673 674 if (get_bits1(gb)) 675 *bd->shift_lsbs = get_bits(gb, 4) + 1; 676 677 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs; 678 679 680 if (!sconf->rlslms) { 681 if (sconf->adapt_order) { 682 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1, 683 2, sconf->max_order + 1)); 684 *bd->opt_order = get_bits(gb, opt_order_length); 685 if (*bd->opt_order > sconf->max_order) { 686 *bd->opt_order = sconf->max_order; 687 av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n"); 688 return AVERROR_INVALIDDATA; 689 } 690 } else { 691 *bd->opt_order = sconf->max_order; 692 } 693 if (*bd->opt_order > bd->block_length) { 694 *bd->opt_order = bd->block_length; 695 av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n"); 696 return AVERROR_INVALIDDATA; 697 } 698 opt_order = *bd->opt_order; 699 700 if (opt_order) { 701 int add_base; 702 703 if (sconf->coef_table == 3) { 704 add_base = 0x7F; 705 706 // read coefficient 0 707 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)]; 708 709 // read coefficient 1 710 if (opt_order > 1) 711 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)]; 712 713 // read coefficients 2 to opt_order 714 for (k = 2; k < opt_order; k++) 715 quant_cof[k] = get_bits(gb, 7); 716 } else { 717 int k_max; 718 add_base = 1; 719 720 // read coefficient 0 to 19 721 k_max = FFMIN(opt_order, 20); 722 for (k = 0; k < k_max; k++) { 723 int rice_param = parcor_rice_table[sconf->coef_table][k][1]; 724 int offset = parcor_rice_table[sconf->coef_table][k][0]; 725 quant_cof[k] = decode_rice(gb, rice_param) + offset; 726 if (quant_cof[k] < -64 || quant_cof[k] > 63) { 727 av_log(avctx, AV_LOG_ERROR, 728 "quant_cof %"PRIu32" is out of range.\n", 729 quant_cof[k]); 730 return AVERROR_INVALIDDATA; 731 } 732 } 733 734 // read coefficients 20 to 126 735 k_max = FFMIN(opt_order, 127); 736 for (; k < k_max; k++) 737 quant_cof[k] = decode_rice(gb, 2) + (k & 1); 738 739 // read coefficients 127 to opt_order 740 for (; k < opt_order; k++) 741 quant_cof[k] = decode_rice(gb, 1); 742 743 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64]; 744 745 if (opt_order > 1) 746 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64]; 747 } 748 749 for (k = 2; k < opt_order; k++) 750 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13); 751 } 752 } 753 754 // read LTP gain and lag values 755 if (sconf->long_term_prediction) { 756 *bd->use_ltp = get_bits1(gb); 757 758 if (*bd->use_ltp) { 759 int r, c; 760 761 bd->ltp_gain[0] = decode_rice(gb, 1) << 3; 762 bd->ltp_gain[1] = decode_rice(gb, 2) << 3; 763 764 r = get_unary(gb, 0, 3); 765 c = get_bits(gb, 2); 766 bd->ltp_gain[2] = ltp_gain_values[r][c]; 767 768 bd->ltp_gain[3] = decode_rice(gb, 2) << 3; 769 bd->ltp_gain[4] = decode_rice(gb, 1) << 3; 770 771 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length); 772 *bd->ltp_lag += FFMAX(4, opt_order + 1); 773 } 774 } 775 776 // read first value and residuals in case of a random access block 777 if (bd->ra_block) { 778 if (opt_order) 779 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4); 780 if (opt_order > 1) 781 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max)); 782 if (opt_order > 2) 783 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max)); 784 785 start = FFMIN(opt_order, 3); 786 } 787 788 // read all residuals 789 if (sconf->bgmc) { 790 int delta[8]; 791 unsigned int k [8]; 792 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5); 793 794 // read most significant bits 795 unsigned int high; 796 unsigned int low; 797 unsigned int value; 798 799 ff_bgmc_decode_init(gb, &high, &low, &value); 800 801 current_res = bd->raw_samples + start; 802 803 for (sb = 0; sb < sub_blocks; sb++) { 804 unsigned int sb_len = sb_length - (sb ? 0 : start); 805 806 k [sb] = s[sb] > b ? s[sb] - b : 0; 807 delta[sb] = 5 - s[sb] + k[sb]; 808 809 ff_bgmc_decode(gb, sb_len, current_res, 810 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status); 811 812 current_res += sb_len; 813 } 814 815 ff_bgmc_decode_end(gb); 816 817 818 // read least significant bits and tails 819 current_res = bd->raw_samples + start; 820 821 for (sb = 0; sb < sub_blocks; sb++, start = 0) { 822 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]]; 823 unsigned int cur_k = k[sb]; 824 unsigned int cur_s = s[sb]; 825 826 for (; start < sb_length; start++) { 827 int32_t res = *current_res; 828 829 if (res == cur_tail_code) { 830 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10)) 831 << (5 - delta[sb]); 832 833 res = decode_rice(gb, cur_s); 834 835 if (res >= 0) { 836 res += (max_msb ) << cur_k; 837 } else { 838 res -= (max_msb - 1) << cur_k; 839 } 840 } else { 841 if (res > cur_tail_code) 842 res--; 843 844 if (res & 1) 845 res = -res; 846 847 res >>= 1; 848 849 if (cur_k) { 850 res <<= cur_k; 851 res |= get_bits_long(gb, cur_k); 852 } 853 } 854 855 *current_res++ = res; 856 } 857 } 858 } else { 859 current_res = bd->raw_samples + start; 860 861 for (sb = 0; sb < sub_blocks; sb++, start = 0) 862 for (; start < sb_length; start++) 863 *current_res++ = decode_rice(gb, s[sb]); 864 } 865 866 if (!sconf->mc_coding || ctx->js_switch) 867 align_get_bits(gb); 868 869 return 0; 870} 871 872 873/** Decode the block data for a non-constant block 874 */ 875static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd) 876{ 877 ALSSpecificConfig *sconf = &ctx->sconf; 878 unsigned int block_length = bd->block_length; 879 unsigned int smp = 0; 880 unsigned int k; 881 int opt_order = *bd->opt_order; 882 int sb; 883 int64_t y; 884 int32_t *quant_cof = bd->quant_cof; 885 int32_t *lpc_cof = bd->lpc_cof; 886 int32_t *raw_samples = bd->raw_samples; 887 int32_t *raw_samples_end = bd->raw_samples + bd->block_length; 888 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer; 889 890 // reverse long-term prediction 891 if (*bd->use_ltp) { 892 int ltp_smp; 893 894 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) { 895 int center = ltp_smp - *bd->ltp_lag; 896 int begin = FFMAX(0, center - 2); 897 int end = center + 3; 898 int tab = 5 - (end - begin); 899 int base; 900 901 y = 1 << 6; 902 903 for (base = begin; base < end; base++, tab++) 904 y += MUL64(bd->ltp_gain[tab], raw_samples[base]); 905 906 raw_samples[ltp_smp] += y >> 7; 907 } 908 } 909 910 // reconstruct all samples from residuals 911 if (bd->ra_block) { 912 for (smp = 0; smp < opt_order; smp++) { 913 y = 1 << 19; 914 915 for (sb = 0; sb < smp; sb++) 916 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]); 917 918 *raw_samples++ -= y >> 20; 919 parcor_to_lpc(smp, quant_cof, lpc_cof); 920 } 921 } else { 922 for (k = 0; k < opt_order; k++) 923 parcor_to_lpc(k, quant_cof, lpc_cof); 924 925 // store previous samples in case that they have to be altered 926 if (*bd->store_prev_samples) 927 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order, 928 sizeof(*bd->prev_raw_samples) * sconf->max_order); 929 930 // reconstruct difference signal for prediction (joint-stereo) 931 if (bd->js_blocks && bd->raw_other) { 932 int32_t *left, *right; 933 934 if (bd->raw_other > raw_samples) { // D = R - L 935 left = raw_samples; 936 right = bd->raw_other; 937 } else { // D = R - L 938 left = bd->raw_other; 939 right = raw_samples; 940 } 941 942 for (sb = -1; sb >= -sconf->max_order; sb--) 943 raw_samples[sb] = right[sb] - left[sb]; 944 } 945 946 // reconstruct shifted signal 947 if (*bd->shift_lsbs) 948 for (sb = -1; sb >= -sconf->max_order; sb--) 949 raw_samples[sb] >>= *bd->shift_lsbs; 950 } 951 952 // reverse linear prediction coefficients for efficiency 953 lpc_cof = lpc_cof + opt_order; 954 955 for (sb = 0; sb < opt_order; sb++) 956 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)]; 957 958 // reconstruct raw samples 959 raw_samples = bd->raw_samples + smp; 960 lpc_cof = lpc_cof_reversed + opt_order; 961 962 for (; raw_samples < raw_samples_end; raw_samples++) { 963 y = 1 << 19; 964 965 for (sb = -opt_order; sb < 0; sb++) 966 y += MUL64(lpc_cof[sb], raw_samples[sb]); 967 968 *raw_samples -= y >> 20; 969 } 970 971 raw_samples = bd->raw_samples; 972 973 // restore previous samples in case that they have been altered 974 if (*bd->store_prev_samples) 975 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples, 976 sizeof(*raw_samples) * sconf->max_order); 977 978 return 0; 979} 980 981 982/** Read the block data. 983 */ 984static int read_block(ALSDecContext *ctx, ALSBlockData *bd) 985{ 986 int ret; 987 GetBitContext *gb = &ctx->gb; 988 989 *bd->shift_lsbs = 0; 990 // read block type flag and read the samples accordingly 991 if (get_bits1(gb)) { 992 ret = read_var_block_data(ctx, bd); 993 } else { 994 ret = read_const_block_data(ctx, bd); 995 } 996 997 return ret; 998} 999 1000 1001/** Decode the block data. 1002 */ 1003static int decode_block(ALSDecContext *ctx, ALSBlockData *bd) 1004{ 1005 unsigned int smp; 1006 int ret = 0; 1007 1008 // read block type flag and read the samples accordingly 1009 if (*bd->const_block) 1010 decode_const_block_data(ctx, bd); 1011 else 1012 ret = decode_var_block_data(ctx, bd); // always return 0 1013 1014 if (ret < 0) 1015 return ret; 1016 1017 // TODO: read RLSLMS extension data 1018 1019 if (*bd->shift_lsbs) 1020 for (smp = 0; smp < bd->block_length; smp++) 1021 bd->raw_samples[smp] <<= *bd->shift_lsbs; 1022 1023 return 0; 1024} 1025 1026 1027/** Read and decode block data successively. 1028 */ 1029static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd) 1030{ 1031 int ret; 1032 1033 if ((ret = read_block(ctx, bd)) < 0) 1034 return ret; 1035 1036 return decode_block(ctx, bd); 1037} 1038 1039 1040/** Compute the number of samples left to decode for the current frame and 1041 * sets these samples to zero. 1042 */ 1043static void zero_remaining(unsigned int b, unsigned int b_max, 1044 const unsigned int *div_blocks, int32_t *buf) 1045{ 1046 unsigned int count = 0; 1047 1048 while (b < b_max) 1049 count += div_blocks[b++]; 1050 1051 if (count) 1052 memset(buf, 0, sizeof(*buf) * count); 1053} 1054 1055 1056/** Decode blocks independently. 1057 */ 1058static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame, 1059 unsigned int c, const unsigned int *div_blocks, 1060 unsigned int *js_blocks) 1061{ 1062 int ret; 1063 unsigned int b; 1064 ALSBlockData bd = { 0 }; 1065 1066 bd.ra_block = ra_frame; 1067 bd.const_block = ctx->const_block; 1068 bd.shift_lsbs = ctx->shift_lsbs; 1069 bd.opt_order = ctx->opt_order; 1070 bd.store_prev_samples = ctx->store_prev_samples; 1071 bd.use_ltp = ctx->use_ltp; 1072 bd.ltp_lag = ctx->ltp_lag; 1073 bd.ltp_gain = ctx->ltp_gain[0]; 1074 bd.quant_cof = ctx->quant_cof[0]; 1075 bd.lpc_cof = ctx->lpc_cof[0]; 1076 bd.prev_raw_samples = ctx->prev_raw_samples; 1077 bd.raw_samples = ctx->raw_samples[c]; 1078 1079 1080 for (b = 0; b < ctx->num_blocks; b++) { 1081 bd.block_length = div_blocks[b]; 1082 1083 if ((ret = read_decode_block(ctx, &bd)) < 0) { 1084 // damaged block, write zero for the rest of the frame 1085 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples); 1086 return ret; 1087 } 1088 bd.raw_samples += div_blocks[b]; 1089 bd.ra_block = 0; 1090 } 1091 1092 return 0; 1093} 1094 1095 1096/** Decode blocks dependently. 1097 */ 1098static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame, 1099 unsigned int c, const unsigned int *div_blocks, 1100 unsigned int *js_blocks) 1101{ 1102 ALSSpecificConfig *sconf = &ctx->sconf; 1103 unsigned int offset = 0; 1104 unsigned int b; 1105 int ret; 1106 ALSBlockData bd[2] = { { 0 } }; 1107 1108 bd[0].ra_block = ra_frame; 1109 bd[0].const_block = ctx->const_block; 1110 bd[0].shift_lsbs = ctx->shift_lsbs; 1111 bd[0].opt_order = ctx->opt_order; 1112 bd[0].store_prev_samples = ctx->store_prev_samples; 1113 bd[0].use_ltp = ctx->use_ltp; 1114 bd[0].ltp_lag = ctx->ltp_lag; 1115 bd[0].ltp_gain = ctx->ltp_gain[0]; 1116 bd[0].quant_cof = ctx->quant_cof[0]; 1117 bd[0].lpc_cof = ctx->lpc_cof[0]; 1118 bd[0].prev_raw_samples = ctx->prev_raw_samples; 1119 bd[0].js_blocks = *js_blocks; 1120 1121 bd[1].ra_block = ra_frame; 1122 bd[1].const_block = ctx->const_block; 1123 bd[1].shift_lsbs = ctx->shift_lsbs; 1124 bd[1].opt_order = ctx->opt_order; 1125 bd[1].store_prev_samples = ctx->store_prev_samples; 1126 bd[1].use_ltp = ctx->use_ltp; 1127 bd[1].ltp_lag = ctx->ltp_lag; 1128 bd[1].ltp_gain = ctx->ltp_gain[0]; 1129 bd[1].quant_cof = ctx->quant_cof[0]; 1130 bd[1].lpc_cof = ctx->lpc_cof[0]; 1131 bd[1].prev_raw_samples = ctx->prev_raw_samples; 1132 bd[1].js_blocks = *(js_blocks + 1); 1133 1134 // decode all blocks 1135 for (b = 0; b < ctx->num_blocks; b++) { 1136 unsigned int s; 1137 1138 bd[0].block_length = div_blocks[b]; 1139 bd[1].block_length = div_blocks[b]; 1140 1141 bd[0].raw_samples = ctx->raw_samples[c ] + offset; 1142 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset; 1143 1144 bd[0].raw_other = bd[1].raw_samples; 1145 bd[1].raw_other = bd[0].raw_samples; 1146 1147 if ((ret = read_decode_block(ctx, &bd[0])) < 0 || 1148 (ret = read_decode_block(ctx, &bd[1])) < 0) 1149 goto fail; 1150 1151 // reconstruct joint-stereo blocks 1152 if (bd[0].js_blocks) { 1153 if (bd[1].js_blocks) 1154 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n"); 1155 1156 for (s = 0; s < div_blocks[b]; s++) 1157 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s]; 1158 } else if (bd[1].js_blocks) { 1159 for (s = 0; s < div_blocks[b]; s++) 1160 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s]; 1161 } 1162 1163 offset += div_blocks[b]; 1164 bd[0].ra_block = 0; 1165 bd[1].ra_block = 0; 1166 } 1167 1168 // store carryover raw samples, 1169 // the others channel raw samples are stored by the calling function. 1170 memmove(ctx->raw_samples[c] - sconf->max_order, 1171 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length, 1172 sizeof(*ctx->raw_samples[c]) * sconf->max_order); 1173 1174 return 0; 1175fail: 1176 // damaged block, write zero for the rest of the frame 1177 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples); 1178 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples); 1179 return ret; 1180} 1181 1182static inline int als_weighting(GetBitContext *gb, int k, int off) 1183{ 1184 int idx = av_clip(decode_rice(gb, k) + off, 1185 0, FF_ARRAY_ELEMS(mcc_weightings) - 1); 1186 return mcc_weightings[idx]; 1187} 1188 1189/** Read the channel data. 1190 */ 1191static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c) 1192{ 1193 GetBitContext *gb = &ctx->gb; 1194 ALSChannelData *current = cd; 1195 unsigned int channels = ctx->avctx->channels; 1196 int entries = 0; 1197 1198 while (entries < channels && !(current->stop_flag = get_bits1(gb))) { 1199 current->master_channel = get_bits_long(gb, av_ceil_log2(channels)); 1200 1201 if (current->master_channel >= channels) { 1202 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n"); 1203 return AVERROR_INVALIDDATA; 1204 } 1205 1206 if (current->master_channel != c) { 1207 current->time_diff_flag = get_bits1(gb); 1208 current->weighting[0] = als_weighting(gb, 1, 16); 1209 current->weighting[1] = als_weighting(gb, 2, 14); 1210 current->weighting[2] = als_weighting(gb, 1, 16); 1211 1212 if (current->time_diff_flag) { 1213 current->weighting[3] = als_weighting(gb, 1, 16); 1214 current->weighting[4] = als_weighting(gb, 1, 16); 1215 current->weighting[5] = als_weighting(gb, 1, 16); 1216 1217 current->time_diff_sign = get_bits1(gb); 1218 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3; 1219 } 1220 } 1221 1222 current++; 1223 entries++; 1224 } 1225 1226 if (entries == channels) { 1227 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n"); 1228 return AVERROR_INVALIDDATA; 1229 } 1230 1231 align_get_bits(gb); 1232 return 0; 1233} 1234 1235 1236/** Recursively reverts the inter-channel correlation for a block. 1237 */ 1238static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd, 1239 ALSChannelData **cd, int *reverted, 1240 unsigned int offset, int c) 1241{ 1242 ALSChannelData *ch = cd[c]; 1243 unsigned int dep = 0; 1244 unsigned int channels = ctx->avctx->channels; 1245 1246 if (reverted[c]) 1247 return 0; 1248 1249 reverted[c] = 1; 1250 1251 while (dep < channels && !ch[dep].stop_flag) { 1252 revert_channel_correlation(ctx, bd, cd, reverted, offset, 1253 ch[dep].master_channel); 1254 1255 dep++; 1256 } 1257 1258 if (dep == channels) { 1259 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n"); 1260 return AVERROR_INVALIDDATA; 1261 } 1262 1263 bd->const_block = ctx->const_block + c; 1264 bd->shift_lsbs = ctx->shift_lsbs + c; 1265 bd->opt_order = ctx->opt_order + c; 1266 bd->store_prev_samples = ctx->store_prev_samples + c; 1267 bd->use_ltp = ctx->use_ltp + c; 1268 bd->ltp_lag = ctx->ltp_lag + c; 1269 bd->ltp_gain = ctx->ltp_gain[c]; 1270 bd->lpc_cof = ctx->lpc_cof[c]; 1271 bd->quant_cof = ctx->quant_cof[c]; 1272 bd->raw_samples = ctx->raw_samples[c] + offset; 1273 1274 for (dep = 0; !ch[dep].stop_flag; dep++) { 1275 unsigned int smp; 1276 unsigned int begin = 1; 1277 unsigned int end = bd->block_length - 1; 1278 int64_t y; 1279 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset; 1280 1281 if (ch[dep].master_channel == c) 1282 continue; 1283 1284 if (ch[dep].time_diff_flag) { 1285 int t = ch[dep].time_diff_index; 1286 1287 if (ch[dep].time_diff_sign) { 1288 t = -t; 1289 begin -= t; 1290 } else { 1291 end -= t; 1292 } 1293 1294 for (smp = begin; smp < end; smp++) { 1295 y = (1 << 6) + 1296 MUL64(ch[dep].weighting[0], master[smp - 1 ]) + 1297 MUL64(ch[dep].weighting[1], master[smp ]) + 1298 MUL64(ch[dep].weighting[2], master[smp + 1 ]) + 1299 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) + 1300 MUL64(ch[dep].weighting[4], master[smp + t]) + 1301 MUL64(ch[dep].weighting[5], master[smp + 1 + t]); 1302 1303 bd->raw_samples[smp] += y >> 7; 1304 } 1305 } else { 1306 for (smp = begin; smp < end; smp++) { 1307 y = (1 << 6) + 1308 MUL64(ch[dep].weighting[0], master[smp - 1]) + 1309 MUL64(ch[dep].weighting[1], master[smp ]) + 1310 MUL64(ch[dep].weighting[2], master[smp + 1]); 1311 1312 bd->raw_samples[smp] += y >> 7; 1313 } 1314 } 1315 } 1316 1317 return 0; 1318} 1319 1320 1321/** Read the frame data. 1322 */ 1323static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame) 1324{ 1325 ALSSpecificConfig *sconf = &ctx->sconf; 1326 AVCodecContext *avctx = ctx->avctx; 1327 GetBitContext *gb = &ctx->gb; 1328 unsigned int div_blocks[32]; ///< block sizes. 1329 unsigned int c; 1330 unsigned int js_blocks[2]; 1331 uint32_t bs_info = 0; 1332 int ret; 1333 1334 // skip the size of the ra unit if present in the frame 1335 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame) 1336 skip_bits_long(gb, 32); 1337 1338 if (sconf->mc_coding && sconf->joint_stereo) { 1339 ctx->js_switch = get_bits1(gb); 1340 align_get_bits(gb); 1341 } 1342 1343 if (!sconf->mc_coding || ctx->js_switch) { 1344 int independent_bs = !sconf->joint_stereo; 1345 1346 for (c = 0; c < avctx->channels; c++) { 1347 js_blocks[0] = 0; 1348 js_blocks[1] = 0; 1349 1350 get_block_sizes(ctx, div_blocks, &bs_info); 1351 1352 // if joint_stereo and block_switching is set, independent decoding 1353 // is signaled via the first bit of bs_info 1354 if (sconf->joint_stereo && sconf->block_switching) 1355 if (bs_info >> 31) 1356 independent_bs = 2; 1357 1358 // if this is the last channel, it has to be decoded independently 1359 if (c == avctx->channels - 1) 1360 independent_bs = 1; 1361 1362 if (independent_bs) { 1363 ret = decode_blocks_ind(ctx, ra_frame, c, 1364 div_blocks, js_blocks); 1365 if (ret < 0) 1366 return ret; 1367 independent_bs--; 1368 } else { 1369 ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks); 1370 if (ret < 0) 1371 return ret; 1372 1373 c++; 1374 } 1375 1376 // store carryover raw samples 1377 memmove(ctx->raw_samples[c] - sconf->max_order, 1378 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length, 1379 sizeof(*ctx->raw_samples[c]) * sconf->max_order); 1380 } 1381 } else { // multi-channel coding 1382 ALSBlockData bd = { 0 }; 1383 int b, ret; 1384 int *reverted_channels = ctx->reverted_channels; 1385 unsigned int offset = 0; 1386 1387 for (c = 0; c < avctx->channels; c++) 1388 if (ctx->chan_data[c] < ctx->chan_data_buffer) { 1389 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n"); 1390 return AVERROR_INVALIDDATA; 1391 } 1392 1393 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels); 1394 1395 bd.ra_block = ra_frame; 1396 bd.prev_raw_samples = ctx->prev_raw_samples; 1397 1398 get_block_sizes(ctx, div_blocks, &bs_info); 1399 1400 for (b = 0; b < ctx->num_blocks; b++) { 1401 bd.block_length = div_blocks[b]; 1402 if (bd.block_length <= 0) { 1403 av_log(ctx->avctx, AV_LOG_WARNING, 1404 "Invalid block length %u in channel data!\n", 1405 bd.block_length); 1406 continue; 1407 } 1408 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; 1420 bd.raw_other = NULL; 1421 1422 if ((ret = read_block(ctx, &bd)) < 0) 1423 return ret; 1424 if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0) 1425 return ret; 1426 } 1427 1428 for (c = 0; c < avctx->channels; c++) { 1429 ret = revert_channel_correlation(ctx, &bd, ctx->chan_data, 1430 reverted_channels, offset, c); 1431 if (ret < 0) 1432 return ret; 1433 } 1434 for (c = 0; c < avctx->channels; c++) { 1435 bd.const_block = ctx->const_block + c; 1436 bd.shift_lsbs = ctx->shift_lsbs + c; 1437 bd.opt_order = ctx->opt_order + c; 1438 bd.store_prev_samples = ctx->store_prev_samples + c; 1439 bd.use_ltp = ctx->use_ltp + c; 1440 bd.ltp_lag = ctx->ltp_lag + c; 1441 bd.ltp_gain = ctx->ltp_gain[c]; 1442 bd.lpc_cof = ctx->lpc_cof[c]; 1443 bd.quant_cof = ctx->quant_cof[c]; 1444 bd.raw_samples = ctx->raw_samples[c] + offset; 1445 1446 if ((ret = decode_block(ctx, &bd)) < 0) 1447 return ret; 1448 } 1449 1450 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels)); 1451 offset += div_blocks[b]; 1452 bd.ra_block = 0; 1453 } 1454 1455 // store carryover raw samples 1456 for (c = 0; c < avctx->channels; c++) 1457 memmove(ctx->raw_samples[c] - sconf->max_order, 1458 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length, 1459 sizeof(*ctx->raw_samples[c]) * sconf->max_order); 1460 } 1461 1462 // TODO: read_diff_float_data 1463 1464 return 0; 1465} 1466 1467 1468/** Decode an ALS frame. 1469 */ 1470static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, 1471 AVPacket *avpkt) 1472{ 1473 ALSDecContext *ctx = avctx->priv_data; 1474 AVFrame *frame = data; 1475 ALSSpecificConfig *sconf = &ctx->sconf; 1476 const uint8_t *buffer = avpkt->data; 1477 int buffer_size = avpkt->size; 1478 int invalid_frame, ret; 1479 unsigned int c, sample, ra_frame, bytes_read, shift; 1480 1481 init_get_bits(&ctx->gb, buffer, buffer_size * 8); 1482 1483 // In the case that the distance between random access frames is set to zero 1484 // (sconf->ra_distance == 0) no frame is treated as a random access frame. 1485 // For the first frame, if prediction is used, all samples used from the 1486 // previous frame are assumed to be zero. 1487 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance); 1488 1489 // the last frame to decode might have a different length 1490 if (sconf->samples != 0xFFFFFFFF) 1491 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length, 1492 sconf->frame_length); 1493 else 1494 ctx->cur_frame_length = sconf->frame_length; 1495 1496 // decode the frame data 1497 if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0) 1498 av_log(ctx->avctx, AV_LOG_WARNING, 1499 "Reading frame data failed. Skipping RA unit.\n"); 1500 1501 ctx->frame_id++; 1502 1503 /* get output buffer */ 1504 frame->nb_samples = ctx->cur_frame_length; 1505 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) 1506 return ret; 1507 1508 // transform decoded frame into output format 1509 #define INTERLEAVE_OUTPUT(bps) \ 1510 { \ 1511 int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \ 1512 shift = bps - ctx->avctx->bits_per_raw_sample; \ 1513 if (!ctx->cs_switch) { \ 1514 for (sample = 0; sample < ctx->cur_frame_length; sample++) \ 1515 for (c = 0; c < avctx->channels; c++) \ 1516 *dest++ = ctx->raw_samples[c][sample] << shift; \ 1517 } else { \ 1518 for (sample = 0; sample < ctx->cur_frame_length; sample++) \ 1519 for (c = 0; c < avctx->channels; c++) \ 1520 *dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] << shift; \ 1521 } \ 1522 } 1523 1524 if (ctx->avctx->bits_per_raw_sample <= 16) { 1525 INTERLEAVE_OUTPUT(16) 1526 } else { 1527 INTERLEAVE_OUTPUT(32) 1528 } 1529 1530 // update CRC 1531 if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) { 1532 int swap = HAVE_BIGENDIAN != sconf->msb_first; 1533 1534 if (ctx->avctx->bits_per_raw_sample == 24) { 1535 int32_t *src = (int32_t *)frame->data[0]; 1536 1537 for (sample = 0; 1538 sample < ctx->cur_frame_length * avctx->channels; 1539 sample++) { 1540 int32_t v; 1541 1542 if (swap) 1543 v = av_bswap32(src[sample]); 1544 else 1545 v = src[sample]; 1546 if (!HAVE_BIGENDIAN) 1547 v >>= 8; 1548 1549 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3); 1550 } 1551 } else { 1552 uint8_t *crc_source; 1553 1554 if (swap) { 1555 if (ctx->avctx->bits_per_raw_sample <= 16) { 1556 int16_t *src = (int16_t*) frame->data[0]; 1557 int16_t *dest = (int16_t*) ctx->crc_buffer; 1558 for (sample = 0; 1559 sample < ctx->cur_frame_length * avctx->channels; 1560 sample++) 1561 *dest++ = av_bswap16(src[sample]); 1562 } else { 1563 ctx->bdsp.bswap_buf((uint32_t *) ctx->crc_buffer, 1564 (uint32_t *) frame->data[0], 1565 ctx->cur_frame_length * avctx->channels); 1566 } 1567 crc_source = ctx->crc_buffer; 1568 } else { 1569 crc_source = frame->data[0]; 1570 } 1571 1572 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source, 1573 ctx->cur_frame_length * avctx->channels * 1574 av_get_bytes_per_sample(avctx->sample_fmt)); 1575 } 1576 1577 1578 // check CRC sums if this is the last frame 1579 if (ctx->cur_frame_length != sconf->frame_length && 1580 ctx->crc_org != ctx->crc) { 1581 av_log(avctx, AV_LOG_ERROR, "CRC error.\n"); 1582 if (avctx->err_recognition & AV_EF_EXPLODE) 1583 return AVERROR_INVALIDDATA; 1584 } 1585 } 1586 1587 *got_frame_ptr = 1; 1588 1589 bytes_read = invalid_frame ? buffer_size : 1590 (get_bits_count(&ctx->gb) + 7) >> 3; 1591 1592 return bytes_read; 1593} 1594 1595 1596/** Uninitialize the ALS decoder. 1597 */ 1598static av_cold int decode_end(AVCodecContext *avctx) 1599{ 1600 ALSDecContext *ctx = avctx->priv_data; 1601 1602 av_freep(&ctx->sconf.chan_pos); 1603 1604 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status); 1605 1606 av_freep(&ctx->const_block); 1607 av_freep(&ctx->shift_lsbs); 1608 av_freep(&ctx->opt_order); 1609 av_freep(&ctx->store_prev_samples); 1610 av_freep(&ctx->use_ltp); 1611 av_freep(&ctx->ltp_lag); 1612 av_freep(&ctx->ltp_gain); 1613 av_freep(&ctx->ltp_gain_buffer); 1614 av_freep(&ctx->quant_cof); 1615 av_freep(&ctx->lpc_cof); 1616 av_freep(&ctx->quant_cof_buffer); 1617 av_freep(&ctx->lpc_cof_buffer); 1618 av_freep(&ctx->lpc_cof_reversed_buffer); 1619 av_freep(&ctx->prev_raw_samples); 1620 av_freep(&ctx->raw_samples); 1621 av_freep(&ctx->raw_buffer); 1622 av_freep(&ctx->chan_data); 1623 av_freep(&ctx->chan_data_buffer); 1624 av_freep(&ctx->reverted_channels); 1625 av_freep(&ctx->crc_buffer); 1626 1627 return 0; 1628} 1629 1630 1631/** Initialize the ALS decoder. 1632 */ 1633static av_cold int decode_init(AVCodecContext *avctx) 1634{ 1635 unsigned int c; 1636 unsigned int channel_size; 1637 int num_buffers, ret; 1638 ALSDecContext *ctx = avctx->priv_data; 1639 ALSSpecificConfig *sconf = &ctx->sconf; 1640 ctx->avctx = avctx; 1641 1642 if (!avctx->extradata) { 1643 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n"); 1644 return AVERROR_INVALIDDATA; 1645 } 1646 1647 if ((ret = read_specific_config(ctx)) < 0) { 1648 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n"); 1649 goto fail; 1650 } 1651 1652 if ((ret = check_specific_config(ctx)) < 0) { 1653 goto fail; 1654 } 1655 1656 if (sconf->bgmc) { 1657 ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status); 1658 if (ret < 0) 1659 goto fail; 1660 } 1661 if (sconf->floating) { 1662 avctx->sample_fmt = AV_SAMPLE_FMT_FLT; 1663 avctx->bits_per_raw_sample = 32; 1664 } else { 1665 avctx->sample_fmt = sconf->resolution > 1 1666 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16; 1667 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8; 1668 } 1669 1670 // set maximum Rice parameter for progressive decoding based on resolution 1671 // This is not specified in 14496-3 but actually done by the reference 1672 // codec RM22 revision 2. 1673 ctx->s_max = sconf->resolution > 1 ? 31 : 15; 1674 1675 // set lag value for long-term prediction 1676 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) + 1677 (avctx->sample_rate >= 192000); 1678 1679 // allocate quantized parcor coefficient buffer 1680 num_buffers = sconf->mc_coding ? avctx->channels : 1; 1681 1682 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers); 1683 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers); 1684 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) * 1685 num_buffers * sconf->max_order); 1686 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) * 1687 num_buffers * sconf->max_order); 1688 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) * 1689 sconf->max_order); 1690 1691 if (!ctx->quant_cof || !ctx->lpc_cof || 1692 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer || 1693 !ctx->lpc_cof_reversed_buffer) { 1694 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); 1695 ret = AVERROR(ENOMEM); 1696 goto fail; 1697 } 1698 1699 // assign quantized parcor coefficient buffers 1700 for (c = 0; c < num_buffers; c++) { 1701 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order; 1702 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order; 1703 } 1704 1705 // allocate and assign lag and gain data buffer for ltp mode 1706 ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers); 1707 ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers); 1708 ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers); 1709 ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers); 1710 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers); 1711 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers); 1712 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers); 1713 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) * 1714 num_buffers * 5); 1715 1716 if (!ctx->const_block || !ctx->shift_lsbs || 1717 !ctx->opt_order || !ctx->store_prev_samples || 1718 !ctx->use_ltp || !ctx->ltp_lag || 1719 !ctx->ltp_gain || !ctx->ltp_gain_buffer) { 1720 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); 1721 ret = AVERROR(ENOMEM); 1722 goto fail; 1723 } 1724 1725 for (c = 0; c < num_buffers; c++) 1726 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5; 1727 1728 // allocate and assign channel data buffer for mcc mode 1729 if (sconf->mc_coding) { 1730 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) * 1731 num_buffers * num_buffers); 1732 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) * 1733 num_buffers); 1734 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) * 1735 num_buffers); 1736 1737 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) { 1738 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); 1739 ret = AVERROR(ENOMEM); 1740 goto fail; 1741 } 1742 1743 for (c = 0; c < num_buffers; c++) 1744 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers; 1745 } else { 1746 ctx->chan_data = NULL; 1747 ctx->chan_data_buffer = NULL; 1748 ctx->reverted_channels = NULL; 1749 } 1750 1751 channel_size = sconf->frame_length + sconf->max_order; 1752 1753 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order); 1754 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size); 1755 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels); 1756 1757 // allocate previous raw sample buffer 1758 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) { 1759 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); 1760 ret = AVERROR(ENOMEM); 1761 goto fail; 1762 } 1763 1764 // assign raw samples buffers 1765 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order; 1766 for (c = 1; c < avctx->channels; c++) 1767 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size; 1768 1769 // allocate crc buffer 1770 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled && 1771 (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) { 1772 ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) * 1773 ctx->cur_frame_length * 1774 avctx->channels * 1775 av_get_bytes_per_sample(avctx->sample_fmt)); 1776 if (!ctx->crc_buffer) { 1777 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); 1778 ret = AVERROR(ENOMEM); 1779 goto fail; 1780 } 1781 } 1782 1783 ff_bswapdsp_init(&ctx->bdsp); 1784 1785 return 0; 1786 1787fail: 1788 decode_end(avctx); 1789 return ret; 1790} 1791 1792 1793/** Flush (reset) the frame ID after seeking. 1794 */ 1795static av_cold void flush(AVCodecContext *avctx) 1796{ 1797 ALSDecContext *ctx = avctx->priv_data; 1798 1799 ctx->frame_id = 0; 1800} 1801 1802 1803AVCodec ff_als_decoder = { 1804 .name = "als", 1805 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"), 1806 .type = AVMEDIA_TYPE_AUDIO, 1807 .id = AV_CODEC_ID_MP4ALS, 1808 .priv_data_size = sizeof(ALSDecContext), 1809 .init = decode_init, 1810 .close = decode_end, 1811 .decode = decode_frame, 1812 .flush = flush, 1813 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1, 1814}; 1815