diff options
Diffstat (limited to 'ffmpeg1/libavcodec/alsdec.c')
| -rw-r--r-- | ffmpeg1/libavcodec/alsdec.c | 1786 |
1 files changed, 1786 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/alsdec.c b/ffmpeg1/libavcodec/alsdec.c new file mode 100644 index 0000000..96d467c --- /dev/null +++ b/ffmpeg1/libavcodec/alsdec.c @@ -0,0 +1,1786 @@ +/* + * MPEG-4 ALS decoder + * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ googlemail.com> + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * MPEG-4 ALS decoder + * @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com> + */ + + +//#define DEBUG + + +#include "avcodec.h" +#include "get_bits.h" +#include "unary.h" +#include "mpeg4audio.h" +#include "bytestream.h" +#include "bgmc.h" +#include "dsputil.h" +#include "internal.h" +#include "libavutil/samplefmt.h" +#include "libavutil/crc.h" + +#include <stdint.h> + +/** Rice parameters and corresponding index offsets for decoding the + * indices of scaled PARCOR values. The table chosen is set globally + * by the encoder and stored in ALSSpecificConfig. + */ +static const int8_t parcor_rice_table[3][20][2] = { + { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4}, + { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3}, + { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2}, + { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} }, + { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4}, + { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4}, + {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4}, + { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} }, + { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4}, + { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3}, + {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3}, + { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} } +}; + + +/** Scaled PARCOR values used for the first two PARCOR coefficients. + * To be indexed by the Rice coded indices. + * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20) + * Actual values are divided by 32 in order to be stored in 16 bits. + */ +static const int16_t parcor_scaled_values[] = { + -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32, + -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32, + -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32, + -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32, + -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32, + -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32, + -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32, + -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32, + -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32, + -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32, + -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32, + -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32, + -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32, + -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32, + -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32, + -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32, + -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32, + -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32, + -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32, + -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32, + -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32, + -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32, + -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32, + 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32, + 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32, + 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32, + 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32, + 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32, + 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32, + 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32, + 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32, + 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32 +}; + + +/** Gain values of p(0) for long-term prediction. + * To be indexed by the Rice coded indices. + */ +static const uint8_t ltp_gain_values [4][4] = { + { 0, 8, 16, 24}, + {32, 40, 48, 56}, + {64, 70, 76, 82}, + {88, 92, 96, 100} +}; + + +/** Inter-channel weighting factors for multi-channel correlation. + * To be indexed by the Rice coded indices. + */ +static const int16_t mcc_weightings[] = { + 204, 192, 179, 166, 153, 140, 128, 115, + 102, 89, 76, 64, 51, 38, 25, 12, + 0, -12, -25, -38, -51, -64, -76, -89, + -102, -115, -128, -140, -153, -166, -179, -192 +}; + + +/** Tail codes used in arithmetic coding using block Gilbert-Moore codes. + */ +static const uint8_t tail_code[16][6] = { + { 74, 44, 25, 13, 7, 3}, + { 68, 42, 24, 13, 7, 3}, + { 58, 39, 23, 13, 7, 3}, + {126, 70, 37, 19, 10, 5}, + {132, 70, 37, 20, 10, 5}, + {124, 70, 38, 20, 10, 5}, + {120, 69, 37, 20, 11, 5}, + {116, 67, 37, 20, 11, 5}, + {108, 66, 36, 20, 10, 5}, + {102, 62, 36, 20, 10, 5}, + { 88, 58, 34, 19, 10, 5}, + {162, 89, 49, 25, 13, 7}, + {156, 87, 49, 26, 14, 7}, + {150, 86, 47, 26, 14, 7}, + {142, 84, 47, 26, 14, 7}, + {131, 79, 46, 26, 14, 7} +}; + + +enum RA_Flag { + RA_FLAG_NONE, + RA_FLAG_FRAMES, + RA_FLAG_HEADER +}; + + +typedef struct { + uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown + int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit + int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer + int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian + int frame_length; ///< frame length for each frame (last frame may differ) + int ra_distance; ///< distance between RA frames (in frames, 0...255) + enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored + int adapt_order; ///< adaptive order: 1 = on, 0 = off + int coef_table; ///< table index of Rice code parameters + int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off + int max_order; ///< maximum prediction order (0..1023) + int block_switching; ///< number of block switching levels + int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only) + int sb_part; ///< sub-block partition + int joint_stereo; ///< joint stereo: 1 = on, 0 = off + int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off + int chan_config; ///< indicates that a chan_config_info field is present + int chan_sort; ///< channel rearrangement: 1 = on, 0 = off + int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off + int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented. + int *chan_pos; ///< original channel positions + int crc_enabled; ///< enable Cyclic Redundancy Checksum +} ALSSpecificConfig; + + +typedef struct { + int stop_flag; + int master_channel; + int time_diff_flag; + int time_diff_sign; + int time_diff_index; + int weighting[6]; +} ALSChannelData; + + +typedef struct { + AVCodecContext *avctx; + ALSSpecificConfig sconf; + GetBitContext gb; + DSPContext dsp; + const AVCRC *crc_table; + uint32_t crc_org; ///< CRC value of the original input data + uint32_t crc; ///< CRC value calculated from decoded data + unsigned int cur_frame_length; ///< length of the current frame to decode + unsigned int frame_id; ///< the frame ID / number of the current frame + unsigned int js_switch; ///< if true, joint-stereo decoding is enforced + unsigned int cs_switch; ///< if true, channel rearrangement is done + unsigned int num_blocks; ///< number of blocks used in the current frame + unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding + uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC + int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC + int ltp_lag_length; ///< number of bits used for ltp lag value + int *const_block; ///< contains const_block flags for all channels + unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels + unsigned int *opt_order; ///< contains opt_order flags for all channels + int *store_prev_samples; ///< contains store_prev_samples flags for all channels + int *use_ltp; ///< contains use_ltp flags for all channels + int *ltp_lag; ///< contains ltp lag values for all channels + int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel + int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter + int32_t **quant_cof; ///< quantized parcor coefficients for a channel + int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients + int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel + int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter + int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer + ALSChannelData **chan_data; ///< channel data for multi-channel correlation + ALSChannelData *chan_data_buffer; ///< contains channel data for all channels + int *reverted_channels; ///< stores a flag for each reverted channel + int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block + int32_t **raw_samples; ///< decoded raw samples for each channel + int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples + uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check +} ALSDecContext; + + +typedef struct { + unsigned int block_length; ///< number of samples within the block + unsigned int ra_block; ///< if true, this is a random access block + int *const_block; ///< if true, this is a constant value block + int js_blocks; ///< true if this block contains a difference signal + unsigned int *shift_lsbs; ///< shift of values for this block + unsigned int *opt_order; ///< prediction order of this block + int *store_prev_samples;///< if true, carryover samples have to be stored + int *use_ltp; ///< if true, long-term prediction is used + int *ltp_lag; ///< lag value for long-term prediction + int *ltp_gain; ///< gain values for ltp 5-tap filter + int32_t *quant_cof; ///< quantized parcor coefficients + int32_t *lpc_cof; ///< coefficients of the direct form prediction + int32_t *raw_samples; ///< decoded raw samples / residuals for this block + int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block + int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair +} ALSBlockData; + + +static av_cold void dprint_specific_config(ALSDecContext *ctx) +{ +#ifdef DEBUG + AVCodecContext *avctx = ctx->avctx; + ALSSpecificConfig *sconf = &ctx->sconf; + + av_dlog(avctx, "resolution = %i\n", sconf->resolution); + av_dlog(avctx, "floating = %i\n", sconf->floating); + av_dlog(avctx, "frame_length = %i\n", sconf->frame_length); + av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance); + av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag); + av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order); + av_dlog(avctx, "coef_table = %i\n", sconf->coef_table); + av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction); + av_dlog(avctx, "max_order = %i\n", sconf->max_order); + av_dlog(avctx, "block_switching = %i\n", sconf->block_switching); + av_dlog(avctx, "bgmc = %i\n", sconf->bgmc); + av_dlog(avctx, "sb_part = %i\n", sconf->sb_part); + av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo); + av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding); + av_dlog(avctx, "chan_config = %i\n", sconf->chan_config); + av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort); + av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms); + av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info); +#endif +} + + +/** Read an ALSSpecificConfig from a buffer into the output struct. + */ +static av_cold int read_specific_config(ALSDecContext *ctx) +{ + GetBitContext gb; + uint64_t ht_size; + int i, config_offset; + MPEG4AudioConfig m4ac; + ALSSpecificConfig *sconf = &ctx->sconf; + AVCodecContext *avctx = ctx->avctx; + uint32_t als_id, header_size, trailer_size; + int ret; + + if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0) + return ret; + + config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata, + avctx->extradata_size * 8, 1); + + if (config_offset < 0) + return -1; + + skip_bits_long(&gb, config_offset); + + if (get_bits_left(&gb) < (30 << 3)) + return -1; + + // read the fixed items + als_id = get_bits_long(&gb, 32); + avctx->sample_rate = m4ac.sample_rate; + skip_bits_long(&gb, 32); // sample rate already known + sconf->samples = get_bits_long(&gb, 32); + avctx->channels = m4ac.channels; + skip_bits(&gb, 16); // number of channels already known + skip_bits(&gb, 3); // skip file_type + sconf->resolution = get_bits(&gb, 3); + sconf->floating = get_bits1(&gb); + sconf->msb_first = get_bits1(&gb); + sconf->frame_length = get_bits(&gb, 16) + 1; + sconf->ra_distance = get_bits(&gb, 8); + sconf->ra_flag = get_bits(&gb, 2); + sconf->adapt_order = get_bits1(&gb); + sconf->coef_table = get_bits(&gb, 2); + sconf->long_term_prediction = get_bits1(&gb); + sconf->max_order = get_bits(&gb, 10); + sconf->block_switching = get_bits(&gb, 2); + sconf->bgmc = get_bits1(&gb); + sconf->sb_part = get_bits1(&gb); + sconf->joint_stereo = get_bits1(&gb); + sconf->mc_coding = get_bits1(&gb); + sconf->chan_config = get_bits1(&gb); + sconf->chan_sort = get_bits1(&gb); + sconf->crc_enabled = get_bits1(&gb); + sconf->rlslms = get_bits1(&gb); + skip_bits(&gb, 5); // skip 5 reserved bits + skip_bits1(&gb); // skip aux_data_enabled + + + // check for ALSSpecificConfig struct + if (als_id != MKBETAG('A','L','S','\0')) + return -1; + + ctx->cur_frame_length = sconf->frame_length; + + // read channel config + if (sconf->chan_config) + sconf->chan_config_info = get_bits(&gb, 16); + // TODO: use this to set avctx->channel_layout + + + // read channel sorting + if (sconf->chan_sort && avctx->channels > 1) { + int chan_pos_bits = av_ceil_log2(avctx->channels); + int bits_needed = avctx->channels * chan_pos_bits + 7; + if (get_bits_left(&gb) < bits_needed) + return -1; + + if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos)))) + return AVERROR(ENOMEM); + + ctx->cs_switch = 1; + + for (i = 0; i < avctx->channels; i++) { + int idx; + + idx = get_bits(&gb, chan_pos_bits); + if (idx >= avctx->channels) { + av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n"); + ctx->cs_switch = 0; + break; + } + sconf->chan_pos[idx] = i; + } + + align_get_bits(&gb); + } + + + // read fixed header and trailer sizes, + // if size = 0xFFFFFFFF then there is no data field! + if (get_bits_left(&gb) < 64) + return -1; + + header_size = get_bits_long(&gb, 32); + trailer_size = get_bits_long(&gb, 32); + if (header_size == 0xFFFFFFFF) + header_size = 0; + if (trailer_size == 0xFFFFFFFF) + trailer_size = 0; + + ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3; + + + // skip the header and trailer data + if (get_bits_left(&gb) < ht_size) + return -1; + + if (ht_size > INT32_MAX) + return -1; + + skip_bits_long(&gb, ht_size); + + + // initialize CRC calculation + if (sconf->crc_enabled) { + if (get_bits_left(&gb) < 32) + return -1; + + if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) { + ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE); + ctx->crc = 0xFFFFFFFF; + ctx->crc_org = ~get_bits_long(&gb, 32); + } else + skip_bits_long(&gb, 32); + } + + + // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data) + + dprint_specific_config(ctx); + + return 0; +} + + +/** Check the ALSSpecificConfig for unsupported features. + */ +static int check_specific_config(ALSDecContext *ctx) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + int error = 0; + + // report unsupported feature and set error value + #define MISSING_ERR(cond, str, errval) \ + { \ + if (cond) { \ + avpriv_report_missing_feature(ctx->avctx, \ + str); \ + error = errval; \ + } \ + } + + MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME); + MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME); + + return error; +} + + +/** Parse the bs_info field to extract the block partitioning used in + * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2. + */ +static void parse_bs_info(const uint32_t bs_info, unsigned int n, + unsigned int div, unsigned int **div_blocks, + unsigned int *num_blocks) +{ + if (n < 31 && ((bs_info << n) & 0x40000000)) { + // if the level is valid and the investigated bit n is set + // then recursively check both children at bits (2n+1) and (2n+2) + n *= 2; + div += 1; + parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks); + parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks); + } else { + // else the bit is not set or the last level has been reached + // (bit implicitly not set) + **div_blocks = div; + (*div_blocks)++; + (*num_blocks)++; + } +} + + +/** Read and decode a Rice codeword. + */ +static int32_t decode_rice(GetBitContext *gb, unsigned int k) +{ + int max = get_bits_left(gb) - k; + int q = get_unary(gb, 0, max); + int r = k ? get_bits1(gb) : !(q & 1); + + if (k > 1) { + q <<= (k - 1); + q += get_bits_long(gb, k - 1); + } else if (!k) { + q >>= 1; + } + return r ? q : ~q; +} + + +/** Convert PARCOR coefficient k to direct filter coefficient. + */ +static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof) +{ + int i, j; + + for (i = 0, j = k - 1; i < j; i++, j--) { + int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20); + cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20); + cof[i] += tmp1; + } + if (i == j) + cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20); + + cof[k] = par[k]; +} + + +/** Read block switching field if necessary and set actual block sizes. + * Also assure that the block sizes of the last frame correspond to the + * actual number of samples. + */ +static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks, + uint32_t *bs_info) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + GetBitContext *gb = &ctx->gb; + unsigned int *ptr_div_blocks = div_blocks; + unsigned int b; + + if (sconf->block_switching) { + unsigned int bs_info_len = 1 << (sconf->block_switching + 2); + *bs_info = get_bits_long(gb, bs_info_len); + *bs_info <<= (32 - bs_info_len); + } + + ctx->num_blocks = 0; + parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks); + + // The last frame may have an overdetermined block structure given in + // the bitstream. In that case the defined block structure would need + // more samples than available to be consistent. + // The block structure is actually used but the block sizes are adapted + // to fit the actual number of available samples. + // Example: 5 samples, 2nd level block sizes: 2 2 2 2. + // This results in the actual block sizes: 2 2 1 0. + // This is not specified in 14496-3 but actually done by the reference + // codec RM22 revision 2. + // This appears to happen in case of an odd number of samples in the last + // frame which is actually not allowed by the block length switching part + // of 14496-3. + // The ALS conformance files feature an odd number of samples in the last + // frame. + + for (b = 0; b < ctx->num_blocks; b++) + div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b]; + + if (ctx->cur_frame_length != ctx->sconf.frame_length) { + unsigned int remaining = ctx->cur_frame_length; + + for (b = 0; b < ctx->num_blocks; b++) { + if (remaining <= div_blocks[b]) { + div_blocks[b] = remaining; + ctx->num_blocks = b + 1; + break; + } + + remaining -= div_blocks[b]; + } + } +} + + +/** Read the block data for a constant block + */ +static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + AVCodecContext *avctx = ctx->avctx; + GetBitContext *gb = &ctx->gb; + + if (bd->block_length <= 0) + return AVERROR_INVALIDDATA; + + *bd->raw_samples = 0; + *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence) + bd->js_blocks = get_bits1(gb); + + // skip 5 reserved bits + skip_bits(gb, 5); + + if (*bd->const_block) { + unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample; + *bd->raw_samples = get_sbits_long(gb, const_val_bits); + } + + // ensure constant block decoding by reusing this field + *bd->const_block = 1; + + return 0; +} + + +/** Decode the block data for a constant block + */ +static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd) +{ + int smp = bd->block_length - 1; + int32_t val = *bd->raw_samples; + int32_t *dst = bd->raw_samples + 1; + + // write raw samples into buffer + for (; smp; smp--) + *dst++ = val; +} + + +/** Read the block data for a non-constant block + */ +static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + AVCodecContext *avctx = ctx->avctx; + GetBitContext *gb = &ctx->gb; + unsigned int k; + unsigned int s[8]; + unsigned int sx[8]; + unsigned int sub_blocks, log2_sub_blocks, sb_length; + unsigned int start = 0; + unsigned int opt_order; + int sb; + int32_t *quant_cof = bd->quant_cof; + int32_t *current_res; + + + // ensure variable block decoding by reusing this field + *bd->const_block = 0; + + *bd->opt_order = 1; + bd->js_blocks = get_bits1(gb); + + opt_order = *bd->opt_order; + + // determine the number of subblocks for entropy decoding + if (!sconf->bgmc && !sconf->sb_part) { + log2_sub_blocks = 0; + } else { + if (sconf->bgmc && sconf->sb_part) + log2_sub_blocks = get_bits(gb, 2); + else + log2_sub_blocks = 2 * get_bits1(gb); + } + + sub_blocks = 1 << log2_sub_blocks; + + // do not continue in case of a damaged stream since + // block_length must be evenly divisible by sub_blocks + if (bd->block_length & (sub_blocks - 1)) { + av_log(avctx, AV_LOG_WARNING, + "Block length is not evenly divisible by the number of subblocks.\n"); + return -1; + } + + sb_length = bd->block_length >> log2_sub_blocks; + + if (sconf->bgmc) { + s[0] = get_bits(gb, 8 + (sconf->resolution > 1)); + for (k = 1; k < sub_blocks; k++) + s[k] = s[k - 1] + decode_rice(gb, 2); + + for (k = 0; k < sub_blocks; k++) { + sx[k] = s[k] & 0x0F; + s [k] >>= 4; + } + } else { + s[0] = get_bits(gb, 4 + (sconf->resolution > 1)); + for (k = 1; k < sub_blocks; k++) + s[k] = s[k - 1] + decode_rice(gb, 0); + } + for (k = 1; k < sub_blocks; k++) + if (s[k] > 32) { + av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n"); + return AVERROR_INVALIDDATA; + } + + if (get_bits1(gb)) + *bd->shift_lsbs = get_bits(gb, 4) + 1; + + *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs; + + + if (!sconf->rlslms) { + if (sconf->adapt_order) { + int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1, + 2, sconf->max_order + 1)); + *bd->opt_order = get_bits(gb, opt_order_length); + if (*bd->opt_order > sconf->max_order) { + *bd->opt_order = sconf->max_order; + av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n"); + return AVERROR_INVALIDDATA; + } + } else { + *bd->opt_order = sconf->max_order; + } + + opt_order = *bd->opt_order; + + if (opt_order) { + int add_base; + + if (sconf->coef_table == 3) { + add_base = 0x7F; + + // read coefficient 0 + quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)]; + + // read coefficient 1 + if (opt_order > 1) + quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)]; + + // read coefficients 2 to opt_order + for (k = 2; k < opt_order; k++) + quant_cof[k] = get_bits(gb, 7); + } else { + int k_max; + add_base = 1; + + // read coefficient 0 to 19 + k_max = FFMIN(opt_order, 20); + for (k = 0; k < k_max; k++) { + int rice_param = parcor_rice_table[sconf->coef_table][k][1]; + int offset = parcor_rice_table[sconf->coef_table][k][0]; + quant_cof[k] = decode_rice(gb, rice_param) + offset; + if (quant_cof[k] < -64 || quant_cof[k] > 63) { + av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range.\n", quant_cof[k]); + return AVERROR_INVALIDDATA; + } + } + + // read coefficients 20 to 126 + k_max = FFMIN(opt_order, 127); + for (; k < k_max; k++) + quant_cof[k] = decode_rice(gb, 2) + (k & 1); + + // read coefficients 127 to opt_order + for (; k < opt_order; k++) + quant_cof[k] = decode_rice(gb, 1); + + quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64]; + + if (opt_order > 1) + quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64]; + } + + for (k = 2; k < opt_order; k++) + quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13); + } + } + + // read LTP gain and lag values + if (sconf->long_term_prediction) { + *bd->use_ltp = get_bits1(gb); + + if (*bd->use_ltp) { + int r, c; + + bd->ltp_gain[0] = decode_rice(gb, 1) << 3; + bd->ltp_gain[1] = decode_rice(gb, 2) << 3; + + r = get_unary(gb, 0, 3); + c = get_bits(gb, 2); + bd->ltp_gain[2] = ltp_gain_values[r][c]; + + bd->ltp_gain[3] = decode_rice(gb, 2) << 3; + bd->ltp_gain[4] = decode_rice(gb, 1) << 3; + + *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length); + *bd->ltp_lag += FFMAX(4, opt_order + 1); + } + } + + // read first value and residuals in case of a random access block + if (bd->ra_block) { + if (opt_order) + bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4); + if (opt_order > 1) + bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max)); + if (opt_order > 2) + bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max)); + + start = FFMIN(opt_order, 3); + } + + // read all residuals + if (sconf->bgmc) { + int delta[8]; + unsigned int k [8]; + unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5); + + // read most significant bits + unsigned int high; + unsigned int low; + unsigned int value; + + ff_bgmc_decode_init(gb, &high, &low, &value); + + current_res = bd->raw_samples + start; + + for (sb = 0; sb < sub_blocks; sb++) { + unsigned int sb_len = sb_length - (sb ? 0 : start); + + k [sb] = s[sb] > b ? s[sb] - b : 0; + delta[sb] = 5 - s[sb] + k[sb]; + + ff_bgmc_decode(gb, sb_len, current_res, + delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status); + + current_res += sb_len; + } + + ff_bgmc_decode_end(gb); + + + // read least significant bits and tails + current_res = bd->raw_samples + start; + + for (sb = 0; sb < sub_blocks; sb++, start = 0) { + unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]]; + unsigned int cur_k = k[sb]; + unsigned int cur_s = s[sb]; + + for (; start < sb_length; start++) { + int32_t res = *current_res; + + if (res == cur_tail_code) { + unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10)) + << (5 - delta[sb]); + + res = decode_rice(gb, cur_s); + + if (res >= 0) { + res += (max_msb ) << cur_k; + } else { + res -= (max_msb - 1) << cur_k; + } + } else { + if (res > cur_tail_code) + res--; + + if (res & 1) + res = -res; + + res >>= 1; + + if (cur_k) { + res <<= cur_k; + res |= get_bits_long(gb, cur_k); + } + } + + *current_res++ = res; + } + } + } else { + current_res = bd->raw_samples + start; + + for (sb = 0; sb < sub_blocks; sb++, start = 0) + for (; start < sb_length; start++) + *current_res++ = decode_rice(gb, s[sb]); + } + + if (!sconf->mc_coding || ctx->js_switch) + align_get_bits(gb); + + return 0; +} + + +/** Decode the block data for a non-constant block + */ +static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + unsigned int block_length = bd->block_length; + unsigned int smp = 0; + unsigned int k; + int opt_order = *bd->opt_order; + int sb; + int64_t y; + int32_t *quant_cof = bd->quant_cof; + int32_t *lpc_cof = bd->lpc_cof; + int32_t *raw_samples = bd->raw_samples; + int32_t *raw_samples_end = bd->raw_samples + bd->block_length; + int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer; + + // reverse long-term prediction + if (*bd->use_ltp) { + int ltp_smp; + + for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) { + int center = ltp_smp - *bd->ltp_lag; + int begin = FFMAX(0, center - 2); + int end = center + 3; + int tab = 5 - (end - begin); + int base; + + y = 1 << 6; + + for (base = begin; base < end; base++, tab++) + y += MUL64(bd->ltp_gain[tab], raw_samples[base]); + + raw_samples[ltp_smp] += y >> 7; + } + } + + // reconstruct all samples from residuals + if (bd->ra_block) { + for (smp = 0; smp < opt_order; smp++) { + y = 1 << 19; + + for (sb = 0; sb < smp; sb++) + y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]); + + *raw_samples++ -= y >> 20; + parcor_to_lpc(smp, quant_cof, lpc_cof); + } + } else { + for (k = 0; k < opt_order; k++) + parcor_to_lpc(k, quant_cof, lpc_cof); + + // store previous samples in case that they have to be altered + if (*bd->store_prev_samples) + memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order, + sizeof(*bd->prev_raw_samples) * sconf->max_order); + + // reconstruct difference signal for prediction (joint-stereo) + if (bd->js_blocks && bd->raw_other) { + int32_t *left, *right; + + if (bd->raw_other > raw_samples) { // D = R - L + left = raw_samples; + right = bd->raw_other; + } else { // D = R - L + left = bd->raw_other; + right = raw_samples; + } + + for (sb = -1; sb >= -sconf->max_order; sb--) + raw_samples[sb] = right[sb] - left[sb]; + } + + // reconstruct shifted signal + if (*bd->shift_lsbs) + for (sb = -1; sb >= -sconf->max_order; sb--) + raw_samples[sb] >>= *bd->shift_lsbs; + } + + // reverse linear prediction coefficients for efficiency + lpc_cof = lpc_cof + opt_order; + + for (sb = 0; sb < opt_order; sb++) + lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)]; + + // reconstruct raw samples + raw_samples = bd->raw_samples + smp; + lpc_cof = lpc_cof_reversed + opt_order; + + for (; raw_samples < raw_samples_end; raw_samples++) { + y = 1 << 19; + + for (sb = -opt_order; sb < 0; sb++) + y += MUL64(lpc_cof[sb], raw_samples[sb]); + + *raw_samples -= y >> 20; + } + + raw_samples = bd->raw_samples; + + // restore previous samples in case that they have been altered + if (*bd->store_prev_samples) + memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples, + sizeof(*raw_samples) * sconf->max_order); + + return 0; +} + + +/** Read the block data. + */ +static int read_block(ALSDecContext *ctx, ALSBlockData *bd) +{ + GetBitContext *gb = &ctx->gb; + int ret; + + *bd->shift_lsbs = 0; + // read block type flag and read the samples accordingly + if (get_bits1(gb)) { + if ((ret = read_var_block_data(ctx, bd)) < 0) + return ret; + } else { + if ((ret = read_const_block_data(ctx, bd)) < 0) + return ret; + } + + return 0; +} + + +/** Decode the block data. + */ +static int decode_block(ALSDecContext *ctx, ALSBlockData *bd) +{ + unsigned int smp; + + // read block type flag and read the samples accordingly + if (*bd->const_block) + decode_const_block_data(ctx, bd); + else if (decode_var_block_data(ctx, bd)) + return -1; + + // TODO: read RLSLMS extension data + + if (*bd->shift_lsbs) + for (smp = 0; smp < bd->block_length; smp++) + bd->raw_samples[smp] <<= *bd->shift_lsbs; + + return 0; +} + + +/** Read and decode block data successively. + */ +static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd) +{ + int ret; + + ret = read_block(ctx, bd); + + if (ret) + return ret; + + ret = decode_block(ctx, bd); + + return ret; +} + + +/** Compute the number of samples left to decode for the current frame and + * sets these samples to zero. + */ +static void zero_remaining(unsigned int b, unsigned int b_max, + const unsigned int *div_blocks, int32_t *buf) +{ + unsigned int count = 0; + + while (b < b_max) + count += div_blocks[b++]; + + if (count) + memset(buf, 0, sizeof(*buf) * count); +} + + +/** Decode blocks independently. + */ +static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame, + unsigned int c, const unsigned int *div_blocks, + unsigned int *js_blocks) +{ + unsigned int b; + ALSBlockData bd = { 0 }; + + bd.ra_block = ra_frame; + bd.const_block = ctx->const_block; + bd.shift_lsbs = ctx->shift_lsbs; + bd.opt_order = ctx->opt_order; + bd.store_prev_samples = ctx->store_prev_samples; + bd.use_ltp = ctx->use_ltp; + bd.ltp_lag = ctx->ltp_lag; + bd.ltp_gain = ctx->ltp_gain[0]; + bd.quant_cof = ctx->quant_cof[0]; + bd.lpc_cof = ctx->lpc_cof[0]; + bd.prev_raw_samples = ctx->prev_raw_samples; + bd.raw_samples = ctx->raw_samples[c]; + + + for (b = 0; b < ctx->num_blocks; b++) { + bd.block_length = div_blocks[b]; + + if (read_decode_block(ctx, &bd)) { + // damaged block, write zero for the rest of the frame + zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples); + return -1; + } + bd.raw_samples += div_blocks[b]; + bd.ra_block = 0; + } + + return 0; +} + + +/** Decode blocks dependently. + */ +static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame, + unsigned int c, const unsigned int *div_blocks, + unsigned int *js_blocks) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + unsigned int offset = 0; + unsigned int b; + ALSBlockData bd[2] = { { 0 } }; + + bd[0].ra_block = ra_frame; + bd[0].const_block = ctx->const_block; + bd[0].shift_lsbs = ctx->shift_lsbs; + bd[0].opt_order = ctx->opt_order; + bd[0].store_prev_samples = ctx->store_prev_samples; + bd[0].use_ltp = ctx->use_ltp; + bd[0].ltp_lag = ctx->ltp_lag; + bd[0].ltp_gain = ctx->ltp_gain[0]; + bd[0].quant_cof = ctx->quant_cof[0]; + bd[0].lpc_cof = ctx->lpc_cof[0]; + bd[0].prev_raw_samples = ctx->prev_raw_samples; + bd[0].js_blocks = *js_blocks; + + bd[1].ra_block = ra_frame; + bd[1].const_block = ctx->const_block; + bd[1].shift_lsbs = ctx->shift_lsbs; + bd[1].opt_order = ctx->opt_order; + bd[1].store_prev_samples = ctx->store_prev_samples; + bd[1].use_ltp = ctx->use_ltp; + bd[1].ltp_lag = ctx->ltp_lag; + bd[1].ltp_gain = ctx->ltp_gain[0]; + bd[1].quant_cof = ctx->quant_cof[0]; + bd[1].lpc_cof = ctx->lpc_cof[0]; + bd[1].prev_raw_samples = ctx->prev_raw_samples; + bd[1].js_blocks = *(js_blocks + 1); + + // decode all blocks + for (b = 0; b < ctx->num_blocks; b++) { + unsigned int s; + + bd[0].block_length = div_blocks[b]; + bd[1].block_length = div_blocks[b]; + + bd[0].raw_samples = ctx->raw_samples[c ] + offset; + bd[1].raw_samples = ctx->raw_samples[c + 1] + offset; + + bd[0].raw_other = bd[1].raw_samples; + bd[1].raw_other = bd[0].raw_samples; + + if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) { + // damaged block, write zero for the rest of the frame + zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples); + zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples); + return -1; + } + + // reconstruct joint-stereo blocks + if (bd[0].js_blocks) { + if (bd[1].js_blocks) + av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n"); + + for (s = 0; s < div_blocks[b]; s++) + bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s]; + } else if (bd[1].js_blocks) { + for (s = 0; s < div_blocks[b]; s++) + bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s]; + } + + offset += div_blocks[b]; + bd[0].ra_block = 0; + bd[1].ra_block = 0; + } + + // store carryover raw samples, + // the others channel raw samples are stored by the calling function. + memmove(ctx->raw_samples[c] - sconf->max_order, + ctx->raw_samples[c] - sconf->max_order + sconf->frame_length, + sizeof(*ctx->raw_samples[c]) * sconf->max_order); + + return 0; +} + + +/** Read the channel data. + */ +static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c) +{ + GetBitContext *gb = &ctx->gb; + ALSChannelData *current = cd; + unsigned int channels = ctx->avctx->channels; + int entries = 0; + + while (entries < channels && !(current->stop_flag = get_bits1(gb))) { + current->master_channel = get_bits_long(gb, av_ceil_log2(channels)); + + if (current->master_channel >= channels) { + av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n"); + return -1; + } + + if (current->master_channel != c) { + current->time_diff_flag = get_bits1(gb); + current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)]; + current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 31)]; + current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)]; + + if (current->time_diff_flag) { + current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)]; + current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)]; + current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 31)]; + + current->time_diff_sign = get_bits1(gb); + current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3; + } + } + + current++; + entries++; + } + + if (entries == channels) { + av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n"); + return -1; + } + + align_get_bits(gb); + return 0; +} + + +/** Recursively reverts the inter-channel correlation for a block. + */ +static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd, + ALSChannelData **cd, int *reverted, + unsigned int offset, int c) +{ + ALSChannelData *ch = cd[c]; + unsigned int dep = 0; + unsigned int channels = ctx->avctx->channels; + + if (reverted[c]) + return 0; + + reverted[c] = 1; + + while (dep < channels && !ch[dep].stop_flag) { + revert_channel_correlation(ctx, bd, cd, reverted, offset, + ch[dep].master_channel); + + dep++; + } + + if (dep == channels) { + av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n"); + return -1; + } + + bd->const_block = ctx->const_block + c; + bd->shift_lsbs = ctx->shift_lsbs + c; + bd->opt_order = ctx->opt_order + c; + bd->store_prev_samples = ctx->store_prev_samples + c; + bd->use_ltp = ctx->use_ltp + c; + bd->ltp_lag = ctx->ltp_lag + c; + bd->ltp_gain = ctx->ltp_gain[c]; + bd->lpc_cof = ctx->lpc_cof[c]; + bd->quant_cof = ctx->quant_cof[c]; + bd->raw_samples = ctx->raw_samples[c] + offset; + + dep = 0; + while (!ch[dep].stop_flag) { + unsigned int smp; + unsigned int begin = 1; + unsigned int end = bd->block_length - 1; + int64_t y; + int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset; + + if (ch[dep].time_diff_flag) { + int t = ch[dep].time_diff_index; + + if (ch[dep].time_diff_sign) { + t = -t; + begin -= t; + } else { + end -= t; + } + + for (smp = begin; smp < end; smp++) { + y = (1 << 6) + + MUL64(ch[dep].weighting[0], master[smp - 1 ]) + + MUL64(ch[dep].weighting[1], master[smp ]) + + MUL64(ch[dep].weighting[2], master[smp + 1 ]) + + MUL64(ch[dep].weighting[3], master[smp - 1 + t]) + + MUL64(ch[dep].weighting[4], master[smp + t]) + + MUL64(ch[dep].weighting[5], master[smp + 1 + t]); + + bd->raw_samples[smp] += y >> 7; + } + } else { + for (smp = begin; smp < end; smp++) { + y = (1 << 6) + + MUL64(ch[dep].weighting[0], master[smp - 1]) + + MUL64(ch[dep].weighting[1], master[smp ]) + + MUL64(ch[dep].weighting[2], master[smp + 1]); + + bd->raw_samples[smp] += y >> 7; + } + } + + dep++; + } + + return 0; +} + + +/** Read the frame data. + */ +static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame) +{ + ALSSpecificConfig *sconf = &ctx->sconf; + AVCodecContext *avctx = ctx->avctx; + GetBitContext *gb = &ctx->gb; + unsigned int div_blocks[32]; ///< block sizes. + unsigned int c; + unsigned int js_blocks[2]; + + uint32_t bs_info = 0; + + // skip the size of the ra unit if present in the frame + if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame) + skip_bits_long(gb, 32); + + if (sconf->mc_coding && sconf->joint_stereo) { + ctx->js_switch = get_bits1(gb); + align_get_bits(gb); + } + + if (!sconf->mc_coding || ctx->js_switch) { + int independent_bs = !sconf->joint_stereo; + + for (c = 0; c < avctx->channels; c++) { + js_blocks[0] = 0; + js_blocks[1] = 0; + + get_block_sizes(ctx, div_blocks, &bs_info); + + // if joint_stereo and block_switching is set, independent decoding + // is signaled via the first bit of bs_info + if (sconf->joint_stereo && sconf->block_switching) + if (bs_info >> 31) + independent_bs = 2; + + // if this is the last channel, it has to be decoded independently + if (c == avctx->channels - 1) + independent_bs = 1; + + if (independent_bs) { + if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks)) + return -1; + + independent_bs--; + } else { + if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks)) + return -1; + + c++; + } + + // store carryover raw samples + memmove(ctx->raw_samples[c] - sconf->max_order, + ctx->raw_samples[c] - sconf->max_order + sconf->frame_length, + sizeof(*ctx->raw_samples[c]) * sconf->max_order); + } + } else { // multi-channel coding + ALSBlockData bd = { 0 }; + int b, ret; + int *reverted_channels = ctx->reverted_channels; + unsigned int offset = 0; + + for (c = 0; c < avctx->channels; c++) + if (ctx->chan_data[c] < ctx->chan_data_buffer) { + av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n"); + return -1; + } + + memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels); + + bd.ra_block = ra_frame; + bd.prev_raw_samples = ctx->prev_raw_samples; + + get_block_sizes(ctx, div_blocks, &bs_info); + + for (b = 0; b < ctx->num_blocks; b++) { + bd.block_length = div_blocks[b]; + + for (c = 0; c < avctx->channels; c++) { + bd.const_block = ctx->const_block + c; + bd.shift_lsbs = ctx->shift_lsbs + c; + bd.opt_order = ctx->opt_order + c; + bd.store_prev_samples = ctx->store_prev_samples + c; + bd.use_ltp = ctx->use_ltp + c; + bd.ltp_lag = ctx->ltp_lag + c; + bd.ltp_gain = ctx->ltp_gain[c]; + bd.lpc_cof = ctx->lpc_cof[c]; + bd.quant_cof = ctx->quant_cof[c]; + bd.raw_samples = ctx->raw_samples[c] + offset; + bd.raw_other = NULL; + + if ((ret = read_block(ctx, &bd)) < 0) + return ret; + if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0) + return ret; + } + + for (c = 0; c < avctx->channels; c++) + if (revert_channel_correlation(ctx, &bd, ctx->chan_data, + reverted_channels, offset, c)) + return -1; + + for (c = 0; c < avctx->channels; c++) { + bd.const_block = ctx->const_block + c; + bd.shift_lsbs = ctx->shift_lsbs + c; + bd.opt_order = ctx->opt_order + c; + bd.store_prev_samples = ctx->store_prev_samples + c; + bd.use_ltp = ctx->use_ltp + c; + bd.ltp_lag = ctx->ltp_lag + c; + bd.ltp_gain = ctx->ltp_gain[c]; + bd.lpc_cof = ctx->lpc_cof[c]; + bd.quant_cof = ctx->quant_cof[c]; + bd.raw_samples = ctx->raw_samples[c] + offset; + + if ((ret = decode_block(ctx, &bd)) < 0) + return ret; + } + + memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels)); + offset += div_blocks[b]; + bd.ra_block = 0; + } + + // store carryover raw samples + for (c = 0; c < avctx->channels; c++) + memmove(ctx->raw_samples[c] - sconf->max_order, + ctx->raw_samples[c] - sconf->max_order + sconf->frame_length, + sizeof(*ctx->raw_samples[c]) * sconf->max_order); + } + + // TODO: read_diff_float_data + + return 0; +} + + +/** Decode an ALS frame. + */ +static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, + AVPacket *avpkt) +{ + ALSDecContext *ctx = avctx->priv_data; + AVFrame *frame = data; + ALSSpecificConfig *sconf = &ctx->sconf; + const uint8_t *buffer = avpkt->data; + int buffer_size = avpkt->size; + int invalid_frame, ret; + unsigned int c, sample, ra_frame, bytes_read, shift; + + init_get_bits(&ctx->gb, buffer, buffer_size * 8); + + // In the case that the distance between random access frames is set to zero + // (sconf->ra_distance == 0) no frame is treated as a random access frame. + // For the first frame, if prediction is used, all samples used from the + // previous frame are assumed to be zero. + ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance); + + // the last frame to decode might have a different length + if (sconf->samples != 0xFFFFFFFF) + ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length, + sconf->frame_length); + else + ctx->cur_frame_length = sconf->frame_length; + + // decode the frame data + if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0) + av_log(ctx->avctx, AV_LOG_WARNING, + "Reading frame data failed. Skipping RA unit.\n"); + + ctx->frame_id++; + + /* get output buffer */ + frame->nb_samples = ctx->cur_frame_length; + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + + // transform decoded frame into output format + #define INTERLEAVE_OUTPUT(bps) \ + { \ + int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \ + shift = bps - ctx->avctx->bits_per_raw_sample; \ + if (!ctx->cs_switch) { \ + for (sample = 0; sample < ctx->cur_frame_length; sample++) \ + for (c = 0; c < avctx->channels; c++) \ + *dest++ = ctx->raw_samples[c][sample] << shift; \ + } else { \ + for (sample = 0; sample < ctx->cur_frame_length; sample++) \ + for (c = 0; c < avctx->channels; c++) \ + *dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] << shift; \ + } \ + } + + if (ctx->avctx->bits_per_raw_sample <= 16) { + INTERLEAVE_OUTPUT(16) + } else { + INTERLEAVE_OUTPUT(32) + } + + // update CRC + if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) { + int swap = HAVE_BIGENDIAN != sconf->msb_first; + + if (ctx->avctx->bits_per_raw_sample == 24) { + int32_t *src = (int32_t *)frame->data[0]; + + for (sample = 0; + sample < ctx->cur_frame_length * avctx->channels; + sample++) { + int32_t v; + + if (swap) + v = av_bswap32(src[sample]); + else + v = src[sample]; + if (!HAVE_BIGENDIAN) + v >>= 8; + + ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3); + } + } else { + uint8_t *crc_source; + + if (swap) { + if (ctx->avctx->bits_per_raw_sample <= 16) { + int16_t *src = (int16_t*) frame->data[0]; + int16_t *dest = (int16_t*) ctx->crc_buffer; + for (sample = 0; + sample < ctx->cur_frame_length * avctx->channels; + sample++) + *dest++ = av_bswap16(src[sample]); + } else { + ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer, + (uint32_t *)frame->data[0], + ctx->cur_frame_length * avctx->channels); + } + crc_source = ctx->crc_buffer; + } else { + crc_source = frame->data[0]; + } + + ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source, + ctx->cur_frame_length * avctx->channels * + av_get_bytes_per_sample(avctx->sample_fmt)); + } + + + // check CRC sums if this is the last frame + if (ctx->cur_frame_length != sconf->frame_length && + ctx->crc_org != ctx->crc) { + av_log(avctx, AV_LOG_ERROR, "CRC error.\n"); + } + } + + *got_frame_ptr = 1; + + bytes_read = invalid_frame ? buffer_size : + (get_bits_count(&ctx->gb) + 7) >> 3; + + return bytes_read; +} + + +/** Uninitialize the ALS decoder. + */ +static av_cold int decode_end(AVCodecContext *avctx) +{ + ALSDecContext *ctx = avctx->priv_data; + + av_freep(&ctx->sconf.chan_pos); + + ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status); + + av_freep(&ctx->const_block); + av_freep(&ctx->shift_lsbs); + av_freep(&ctx->opt_order); + av_freep(&ctx->store_prev_samples); + av_freep(&ctx->use_ltp); + av_freep(&ctx->ltp_lag); + av_freep(&ctx->ltp_gain); + av_freep(&ctx->ltp_gain_buffer); + av_freep(&ctx->quant_cof); + av_freep(&ctx->lpc_cof); + av_freep(&ctx->quant_cof_buffer); + av_freep(&ctx->lpc_cof_buffer); + av_freep(&ctx->lpc_cof_reversed_buffer); + av_freep(&ctx->prev_raw_samples); + av_freep(&ctx->raw_samples); + av_freep(&ctx->raw_buffer); + av_freep(&ctx->chan_data); + av_freep(&ctx->chan_data_buffer); + av_freep(&ctx->reverted_channels); + av_freep(&ctx->crc_buffer); + + return 0; +} + + +/** Initialize the ALS decoder. + */ +static av_cold int decode_init(AVCodecContext *avctx) +{ + unsigned int c; + unsigned int channel_size; + int num_buffers; + ALSDecContext *ctx = avctx->priv_data; + ALSSpecificConfig *sconf = &ctx->sconf; + ctx->avctx = avctx; + + if (!avctx->extradata) { + av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n"); + return -1; + } + + if (read_specific_config(ctx)) { + av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n"); + decode_end(avctx); + return -1; + } + + if (check_specific_config(ctx)) { + decode_end(avctx); + return -1; + } + + if (sconf->bgmc) + ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status); + + if (sconf->floating) { + avctx->sample_fmt = AV_SAMPLE_FMT_FLT; + avctx->bits_per_raw_sample = 32; + } else { + avctx->sample_fmt = sconf->resolution > 1 + ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16; + avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8; + } + + // set maximum Rice parameter for progressive decoding based on resolution + // This is not specified in 14496-3 but actually done by the reference + // codec RM22 revision 2. + ctx->s_max = sconf->resolution > 1 ? 31 : 15; + + // set lag value for long-term prediction + ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) + + (avctx->sample_rate >= 192000); + + // allocate quantized parcor coefficient buffer + num_buffers = sconf->mc_coding ? avctx->channels : 1; + + ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers); + ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers); + ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) * + num_buffers * sconf->max_order); + ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) * + num_buffers * sconf->max_order); + ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) * + sconf->max_order); + + if (!ctx->quant_cof || !ctx->lpc_cof || + !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer || + !ctx->lpc_cof_reversed_buffer) { + av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); + return AVERROR(ENOMEM); + } + + // assign quantized parcor coefficient buffers + for (c = 0; c < num_buffers; c++) { + ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order; + ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order; + } + + // allocate and assign lag and gain data buffer for ltp mode + ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers); + ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers); + ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers); + ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers); + ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers); + ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers); + ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers); + ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) * + num_buffers * 5); + + if (!ctx->const_block || !ctx->shift_lsbs || + !ctx->opt_order || !ctx->store_prev_samples || + !ctx->use_ltp || !ctx->ltp_lag || + !ctx->ltp_gain || !ctx->ltp_gain_buffer) { + av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); + decode_end(avctx); + return AVERROR(ENOMEM); + } + + for (c = 0; c < num_buffers; c++) + ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5; + + // allocate and assign channel data buffer for mcc mode + if (sconf->mc_coding) { + ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) * + num_buffers * num_buffers); + ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) * + num_buffers); + ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) * + num_buffers); + + if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) { + av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); + decode_end(avctx); + return AVERROR(ENOMEM); + } + + for (c = 0; c < num_buffers; c++) + ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers; + } else { + ctx->chan_data = NULL; + ctx->chan_data_buffer = NULL; + ctx->reverted_channels = NULL; + } + + channel_size = sconf->frame_length + sconf->max_order; + + ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order); + ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size); + ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels); + + // allocate previous raw sample buffer + if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) { + av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); + decode_end(avctx); + return AVERROR(ENOMEM); + } + + // assign raw samples buffers + ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order; + for (c = 1; c < avctx->channels; c++) + ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size; + + // allocate crc buffer + if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled && + (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) { + ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) * + ctx->cur_frame_length * + avctx->channels * + av_get_bytes_per_sample(avctx->sample_fmt)); + if (!ctx->crc_buffer) { + av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n"); + decode_end(avctx); + return AVERROR(ENOMEM); + } + } + + ff_dsputil_init(&ctx->dsp, avctx); + + return 0; +} + + +/** Flush (reset) the frame ID after seeking. + */ +static av_cold void flush(AVCodecContext *avctx) +{ + ALSDecContext *ctx = avctx->priv_data; + + ctx->frame_id = 0; +} + + +AVCodec ff_als_decoder = { + .name = "als", + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_MP4ALS, + .priv_data_size = sizeof(ALSDecContext), + .init = decode_init, + .close = decode_end, + .decode = decode_frame, + .flush = flush, + .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"), +}; |