1633 lines
56 KiB
C
1633 lines
56 KiB
C
/*
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* MPEG-4 ALS decoder
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* Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file libavcodec/alsdec.c
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* MPEG-4 ALS decoder
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* @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
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*/
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//#define DEBUG
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#include "avcodec.h"
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#include "get_bits.h"
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#include "unary.h"
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#include "mpeg4audio.h"
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#include "bytestream.h"
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#include "bgmc.h"
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#include <stdint.h>
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/** Rice parameters and corresponding index offsets for decoding the
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* indices of scaled PARCOR values. The table choosen is set globally
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* by the encoder and stored in ALSSpecificConfig.
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*/
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static const int8_t parcor_rice_table[3][20][2] = {
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{ {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
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{ 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
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{ -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
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{ 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
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{ {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
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{ 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
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{-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
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{ 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
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{ {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
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{ 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
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{-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
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{ 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
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};
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/** Scaled PARCOR values used for the first two PARCOR coefficients.
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* To be indexed by the Rice coded indices.
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* Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
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* Actual values are divided by 32 in order to be stored in 16 bits.
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*/
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static const int16_t parcor_scaled_values[] = {
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-1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
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-1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
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-1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
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-1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
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-1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
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-994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
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-971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
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-944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
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-913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
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-878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
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-838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
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-795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
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-747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
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-695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
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-639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
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-580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
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-516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
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-447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
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-375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
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-299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
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-219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
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-134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
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-46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
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46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
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143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
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244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
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349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
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458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
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571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
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688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
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810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
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935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
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};
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/** Gain values of p(0) for long-term prediction.
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* To be indexed by the Rice coded indices.
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*/
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static const uint8_t ltp_gain_values [4][4] = {
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{ 0, 8, 16, 24},
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{32, 40, 48, 56},
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{64, 70, 76, 82},
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{88, 92, 96, 100}
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};
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/** Inter-channel weighting factors for multi-channel correlation.
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* To be indexed by the Rice coded indices.
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*/
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static const int16_t mcc_weightings[] = {
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204, 192, 179, 166, 153, 140, 128, 115,
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102, 89, 76, 64, 51, 38, 25, 12,
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0, -12, -25, -38, -51, -64, -76, -89,
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-102, -115, -128, -140, -153, -166, -179, -192
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};
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/** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
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*/
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static const uint8_t tail_code[16][6] = {
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{ 74, 44, 25, 13, 7, 3},
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{ 68, 42, 24, 13, 7, 3},
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{ 58, 39, 23, 13, 7, 3},
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{126, 70, 37, 19, 10, 5},
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{132, 70, 37, 20, 10, 5},
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{124, 70, 38, 20, 10, 5},
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{120, 69, 37, 20, 11, 5},
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{116, 67, 37, 20, 11, 5},
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{108, 66, 36, 20, 10, 5},
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{102, 62, 36, 20, 10, 5},
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{ 88, 58, 34, 19, 10, 5},
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{162, 89, 49, 25, 13, 7},
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{156, 87, 49, 26, 14, 7},
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{150, 86, 47, 26, 14, 7},
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{142, 84, 47, 26, 14, 7},
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{131, 79, 46, 26, 14, 7}
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};
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enum RA_Flag {
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RA_FLAG_NONE,
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RA_FLAG_FRAMES,
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RA_FLAG_HEADER
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};
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typedef struct {
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uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
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int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
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int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
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int frame_length; ///< frame length for each frame (last frame may differ)
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int ra_distance; ///< distance between RA frames (in frames, 0...255)
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enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
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int adapt_order; ///< adaptive order: 1 = on, 0 = off
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int coef_table; ///< table index of Rice code parameters
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int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
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int max_order; ///< maximum prediction order (0..1023)
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int block_switching; ///< number of block switching levels
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int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
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int sb_part; ///< sub-block partition
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int joint_stereo; ///< joint stereo: 1 = on, 0 = off
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int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
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int chan_config; ///< indicates that a chan_config_info field is present
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int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
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int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
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int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
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int *chan_pos; ///< original channel positions
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} ALSSpecificConfig;
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typedef struct {
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int stop_flag;
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int master_channel;
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int time_diff_flag;
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int time_diff_sign;
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int time_diff_index;
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int weighting[6];
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} ALSChannelData;
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typedef struct {
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AVCodecContext *avctx;
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ALSSpecificConfig sconf;
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GetBitContext gb;
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unsigned int cur_frame_length; ///< length of the current frame to decode
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unsigned int frame_id; ///< the frame ID / number of the current frame
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unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
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unsigned int num_blocks; ///< number of blocks used in the current frame
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unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
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uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
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unsigned int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
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int ltp_lag_length; ///< number of bits used for ltp lag value
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int *use_ltp; ///< contains use_ltp flags for all channels
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int *ltp_lag; ///< contains ltp lag values for all channels
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int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
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int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
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int32_t **quant_cof; ///< quantized parcor coefficients for a channel
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int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
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int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
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int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
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int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
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ALSChannelData **chan_data; ///< channel data for multi-channel correlation
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ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
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int *reverted_channels; ///< stores a flag for each reverted channel
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int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
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int32_t **raw_samples; ///< decoded raw samples for each channel
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int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
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} ALSDecContext;
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typedef struct {
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unsigned int block_length; ///< number of samples within the block
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unsigned int ra_block; ///< if true, this is a random access block
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int const_block; ///< if true, this is a constant value block
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int32_t const_val; ///< the sample value of a constant block
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int js_blocks; ///< true if this block contains a difference signal
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unsigned int shift_lsbs; ///< shift of values for this block
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unsigned int opt_order; ///< prediction order of this block
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int store_prev_samples;///< if true, carryover samples have to be stored
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int *use_ltp; ///< if true, long-term prediction is used
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int *ltp_lag; ///< lag value for long-term prediction
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int *ltp_gain; ///< gain values for ltp 5-tap filter
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int32_t *quant_cof; ///< quantized parcor coefficients
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int32_t *lpc_cof; ///< coefficients of the direct form prediction
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int32_t *raw_samples; ///< decoded raw samples / residuals for this block
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int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
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int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
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} ALSBlockData;
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static av_cold void dprint_specific_config(ALSDecContext *ctx)
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{
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#ifdef DEBUG
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AVCodecContext *avctx = ctx->avctx;
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ALSSpecificConfig *sconf = &ctx->sconf;
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dprintf(avctx, "resolution = %i\n", sconf->resolution);
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dprintf(avctx, "floating = %i\n", sconf->floating);
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dprintf(avctx, "frame_length = %i\n", sconf->frame_length);
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dprintf(avctx, "ra_distance = %i\n", sconf->ra_distance);
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dprintf(avctx, "ra_flag = %i\n", sconf->ra_flag);
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dprintf(avctx, "adapt_order = %i\n", sconf->adapt_order);
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dprintf(avctx, "coef_table = %i\n", sconf->coef_table);
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dprintf(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
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dprintf(avctx, "max_order = %i\n", sconf->max_order);
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dprintf(avctx, "block_switching = %i\n", sconf->block_switching);
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dprintf(avctx, "bgmc = %i\n", sconf->bgmc);
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dprintf(avctx, "sb_part = %i\n", sconf->sb_part);
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dprintf(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
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dprintf(avctx, "mc_coding = %i\n", sconf->mc_coding);
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dprintf(avctx, "chan_config = %i\n", sconf->chan_config);
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dprintf(avctx, "chan_sort = %i\n", sconf->chan_sort);
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dprintf(avctx, "RLSLMS = %i\n", sconf->rlslms);
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dprintf(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
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#endif
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}
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/** Reads an ALSSpecificConfig from a buffer into the output struct.
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*/
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static av_cold int read_specific_config(ALSDecContext *ctx)
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{
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GetBitContext gb;
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uint64_t ht_size;
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int i, config_offset, crc_enabled;
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MPEG4AudioConfig m4ac;
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ALSSpecificConfig *sconf = &ctx->sconf;
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AVCodecContext *avctx = ctx->avctx;
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uint32_t als_id, header_size, trailer_size;
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init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
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config_offset = ff_mpeg4audio_get_config(&m4ac, avctx->extradata,
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avctx->extradata_size);
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if (config_offset < 0)
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return -1;
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skip_bits_long(&gb, config_offset);
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if (get_bits_left(&gb) < (30 << 3))
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return -1;
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// read the fixed items
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als_id = get_bits_long(&gb, 32);
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avctx->sample_rate = m4ac.sample_rate;
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skip_bits_long(&gb, 32); // sample rate already known
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sconf->samples = get_bits_long(&gb, 32);
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avctx->channels = m4ac.channels;
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skip_bits(&gb, 16); // number of channels already knwon
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skip_bits(&gb, 3); // skip file_type
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sconf->resolution = get_bits(&gb, 3);
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sconf->floating = get_bits1(&gb);
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skip_bits1(&gb); // skip msb_first
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sconf->frame_length = get_bits(&gb, 16) + 1;
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sconf->ra_distance = get_bits(&gb, 8);
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sconf->ra_flag = get_bits(&gb, 2);
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sconf->adapt_order = get_bits1(&gb);
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sconf->coef_table = get_bits(&gb, 2);
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sconf->long_term_prediction = get_bits1(&gb);
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sconf->max_order = get_bits(&gb, 10);
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sconf->block_switching = get_bits(&gb, 2);
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sconf->bgmc = get_bits1(&gb);
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sconf->sb_part = get_bits1(&gb);
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sconf->joint_stereo = get_bits1(&gb);
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sconf->mc_coding = get_bits1(&gb);
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sconf->chan_config = get_bits1(&gb);
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sconf->chan_sort = get_bits1(&gb);
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crc_enabled = get_bits1(&gb);
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sconf->rlslms = get_bits1(&gb);
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skip_bits(&gb, 5); // skip 5 reserved bits
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skip_bits1(&gb); // skip aux_data_enabled
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// check for ALSSpecificConfig struct
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if (als_id != MKBETAG('A','L','S','\0'))
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return -1;
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ctx->cur_frame_length = sconf->frame_length;
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// read channel config
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if (sconf->chan_config)
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sconf->chan_config_info = get_bits(&gb, 16);
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// TODO: use this to set avctx->channel_layout
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// read channel sorting
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if (sconf->chan_sort && avctx->channels > 1) {
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int chan_pos_bits = av_ceil_log2(avctx->channels);
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int bits_needed = avctx->channels * chan_pos_bits + 7;
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if (get_bits_left(&gb) < bits_needed)
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return -1;
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if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
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return AVERROR(ENOMEM);
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for (i = 0; i < avctx->channels; i++)
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sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
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align_get_bits(&gb);
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// TODO: use this to actually do channel sorting
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} else {
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sconf->chan_sort = 0;
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}
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// read fixed header and trailer sizes,
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// if size = 0xFFFFFFFF then there is no data field!
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if (get_bits_left(&gb) < 64)
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return -1;
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header_size = get_bits_long(&gb, 32);
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trailer_size = get_bits_long(&gb, 32);
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if (header_size == 0xFFFFFFFF)
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header_size = 0;
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if (trailer_size == 0xFFFFFFFF)
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trailer_size = 0;
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ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
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// skip the header and trailer data
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if (get_bits_left(&gb) < ht_size)
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return -1;
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if (ht_size > INT32_MAX)
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return -1;
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skip_bits_long(&gb, ht_size);
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// skip the crc data
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if (crc_enabled) {
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if (get_bits_left(&gb) < 32)
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return -1;
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skip_bits_long(&gb, 32);
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}
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// no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
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dprint_specific_config(ctx);
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return 0;
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}
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/** Checks the ALSSpecificConfig for unsupported features.
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*/
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static int check_specific_config(ALSDecContext *ctx)
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{
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ALSSpecificConfig *sconf = &ctx->sconf;
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int error = 0;
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// report unsupported feature and set error value
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#define MISSING_ERR(cond, str, errval) \
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{ \
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if (cond) { \
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av_log_missing_feature(ctx->avctx, str, 0); \
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error = errval; \
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} \
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}
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MISSING_ERR(sconf->floating, "Floating point decoding", -1);
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|
MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
|
|
MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
|
|
|
|
return error;
|
|
}
|
|
|
|
|
|
/** Parses 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)++;
|
|
}
|
|
}
|
|
|
|
|
|
/** Reads and decodes 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;
|
|
}
|
|
|
|
|
|
/** Converts 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];
|
|
}
|
|
|
|
|
|
/** Reads block switching field if necessary and sets actual block sizes.
|
|
* Also assures 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];
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/** Reads the block data for a constant block
|
|
*/
|
|
static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
|
|
{
|
|
ALSSpecificConfig *sconf = &ctx->sconf;
|
|
AVCodecContext *avctx = ctx->avctx;
|
|
GetBitContext *gb = &ctx->gb;
|
|
|
|
bd->const_val = 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->const_val = get_sbits_long(gb, const_val_bits);
|
|
}
|
|
|
|
// ensure constant block decoding by reusing this field
|
|
bd->const_block = 1;
|
|
}
|
|
|
|
|
|
/** Decodes the block data for a constant block
|
|
*/
|
|
static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
|
|
{
|
|
int smp = bd->block_length;
|
|
int32_t val = bd->const_val;
|
|
int32_t *dst = bd->raw_samples;
|
|
|
|
// write raw samples into buffer
|
|
for (; smp; smp--)
|
|
*dst++ = val;
|
|
}
|
|
|
|
|
|
/** Reads 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);
|
|
}
|
|
|
|
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);
|
|
} 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;
|
|
}
|
|
|
|
// 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) {
|
|
bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
|
|
bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
|
|
|
|
bd->ltp_gain[2] = ltp_gain_values[get_unary(gb, 0, 4)][get_bits(gb, 2)];
|
|
|
|
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) {
|
|
unsigned int delta[sub_blocks];
|
|
unsigned int k [sub_blocks];
|
|
unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
|
|
unsigned int i = start;
|
|
|
|
// 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++, i = 0) {
|
|
k [sb] = s[sb] > b ? s[sb] - b : 0;
|
|
delta[sb] = 5 - s[sb] + k[sb];
|
|
|
|
ff_bgmc_decode(gb, sb_length, current_res,
|
|
delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
|
|
|
|
current_res += sb_length;
|
|
}
|
|
|
|
ff_bgmc_decode_end(gb);
|
|
|
|
|
|
// read least significant bits and tails
|
|
i = start;
|
|
current_res = bd->raw_samples + start;
|
|
|
|
for (sb = 0; sb < sub_blocks; sb++, i = 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 (; i < sb_length; i++) {
|
|
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;
|
|
}
|
|
|
|
|
|
/** Decodes 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;
|
|
}
|
|
|
|
|
|
/** Reads the block data.
|
|
*/
|
|
static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
|
|
{
|
|
GetBitContext *gb = &ctx->gb;
|
|
|
|
// read block type flag and read the samples accordingly
|
|
if (get_bits1(gb)) {
|
|
if (read_var_block_data(ctx, bd))
|
|
return -1;
|
|
} else {
|
|
read_const_block_data(ctx, bd);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/** Decodes 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;
|
|
}
|
|
|
|
|
|
/** Reads and decodes 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;
|
|
}
|
|
|
|
|
|
/** Computes 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);
|
|
}
|
|
|
|
|
|
/** Decodes 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;
|
|
|
|
memset(&bd, 0, sizeof(ALSBlockData));
|
|
|
|
bd.ra_block = ra_frame;
|
|
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.shift_lsbs = 0;
|
|
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;
|
|
}
|
|
|
|
|
|
/** Decodes 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];
|
|
|
|
memset(bd, 0, 2 * sizeof(ALSBlockData));
|
|
|
|
bd[0].ra_block = ra_frame;
|
|
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].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].shift_lsbs = 0;
|
|
bd[1].shift_lsbs = 0;
|
|
|
|
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;
|
|
}
|
|
|
|
|
|
/** Reads 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, 32)];
|
|
current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
|
|
current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
|
|
|
|
if (current->time_diff_flag) {
|
|
current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
|
|
current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
|
|
current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
|
|
|
|
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->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;
|
|
}
|
|
|
|
|
|
/** Reads 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;
|
|
int b;
|
|
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(&bd, 0, sizeof(ALSBlockData));
|
|
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.shift_lsbs = 0;
|
|
bd.block_length = div_blocks[b];
|
|
|
|
for (c = 0; c < avctx->channels; 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;
|
|
|
|
read_block(ctx, &bd);
|
|
if (read_channel_data(ctx, ctx->chan_data[c], c))
|
|
return -1;
|
|
}
|
|
|
|
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.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;
|
|
decode_block(ctx, &bd);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
|
|
/** Decodes an ALS frame.
|
|
*/
|
|
static int decode_frame(AVCodecContext *avctx,
|
|
void *data, int *data_size,
|
|
AVPacket *avpkt)
|
|
{
|
|
ALSDecContext *ctx = avctx->priv_data;
|
|
ALSSpecificConfig *sconf = &ctx->sconf;
|
|
const uint8_t *buffer = avpkt->data;
|
|
int buffer_size = avpkt->size;
|
|
int invalid_frame, size;
|
|
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++;
|
|
|
|
// check for size of decoded data
|
|
size = ctx->cur_frame_length * avctx->channels *
|
|
(av_get_bits_per_sample_format(avctx->sample_fmt) >> 3);
|
|
|
|
if (size > *data_size) {
|
|
av_log(avctx, AV_LOG_ERROR, "Decoded data exceeds buffer size.\n");
|
|
return -1;
|
|
}
|
|
|
|
*data_size = size;
|
|
|
|
// transform decoded frame into output format
|
|
#define INTERLEAVE_OUTPUT(bps) \
|
|
{ \
|
|
int##bps##_t *dest = (int##bps##_t*) data; \
|
|
shift = bps - ctx->avctx->bits_per_raw_sample; \
|
|
for (sample = 0; sample < ctx->cur_frame_length; sample++) \
|
|
for (c = 0; c < avctx->channels; c++) \
|
|
*dest++ = ctx->raw_samples[c][sample] << shift; \
|
|
}
|
|
|
|
if (ctx->avctx->bits_per_raw_sample <= 16) {
|
|
INTERLEAVE_OUTPUT(16)
|
|
} else {
|
|
INTERLEAVE_OUTPUT(32)
|
|
}
|
|
|
|
bytes_read = invalid_frame ? buffer_size :
|
|
(get_bits_count(&ctx->gb) + 7) >> 3;
|
|
|
|
return bytes_read;
|
|
}
|
|
|
|
|
|
/** Uninitializes 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->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);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/** Initializes 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 = SAMPLE_FMT_FLT;
|
|
avctx->bits_per_raw_sample = 32;
|
|
} else {
|
|
avctx->sample_fmt = sconf->resolution > 1
|
|
? SAMPLE_FMT_S32 : 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->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->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);
|
|
ctx->chan_data = av_malloc(sizeof(ALSChannelData) *
|
|
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;
|
|
} else {
|
|
ctx->chan_data = NULL;
|
|
ctx->chan_data_buffer = NULL;
|
|
ctx->reverted_channels = NULL;
|
|
}
|
|
|
|
avctx->frame_size = sconf->frame_length;
|
|
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;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/** Flushes (resets) the frame ID after seeking.
|
|
*/
|
|
static av_cold void flush(AVCodecContext *avctx)
|
|
{
|
|
ALSDecContext *ctx = avctx->priv_data;
|
|
|
|
ctx->frame_id = 0;
|
|
}
|
|
|
|
|
|
AVCodec als_decoder = {
|
|
"als",
|
|
CODEC_TYPE_AUDIO,
|
|
CODEC_ID_MP4ALS,
|
|
sizeof(ALSDecContext),
|
|
decode_init,
|
|
NULL,
|
|
decode_end,
|
|
decode_frame,
|
|
.flush = flush,
|
|
.capabilities = CODEC_CAP_SUBFRAMES,
|
|
.long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
|
|
};
|
|
|