xenia-project/FFmpeg
1
0
Fork 0
mirror of https://github.com/xenia-project/FFmpeg.git synced 2024-11-29 14:30:27 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
81a131312d
FFmpeg/libavcodec/alsdec.c
Reinhard Tartler 737eb5976f Merge libavcore into libavutil 
It is pretty hopeless that other considerable projects will adopt
libavutil alone in other projects. Projects that need small footprint
are better off with more specialized libraries such as gnulib or rather
just copy the necessary parts that they need. With this in mind, nobody
is helped by having libavutil and libavcore split. In order to ease
maintenance inside and around FFmpeg and to reduce confusion where to
put common code, avcore's functionality is merged (back) to avutil.

Signed-off-by: Reinhard Tartler <siretart@tauware.de>
2011-02-15 16:18:21 +01:00

1755 lines
61 KiB
C
Raw Blame History

/*
* 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 "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 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;
init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
config_offset = ff_mpeg4audio_get_config(&m4ac, avctx->extradata,
avctx->extradata_size);
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 knwon
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);
for (i = 0; i < avctx->channels; i++)
sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
align_get_bits(&gb);
// TODO: use this to actually do channel sorting
} else {
sconf->chan_sort = 0;
}
// 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->error_recognition >= FF_ER_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) { \
av_log_missing_feature(ctx->avctx, str, 0); \
error = errval; \
} \
}
MISSING_ERR(sconf->floating, "Floating point decoding", -1);
MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
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 void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
{
ALSSpecificConfig *sconf = &ctx->sconf;
AVCodecContext *avctx = ctx->avctx;
GetBitContext *gb = &ctx->gb;
*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;
}
/** 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);
}
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) {
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, 4);
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);
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;
}
/** 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;
*bd->shift_lsbs = 0;
// 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;
}
/** 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;
memset(&bd, 0, sizeof(ALSBlockData));
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];
memset(bd, 0, 2 * sizeof(ALSBlockData));
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, 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->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;
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.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;
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.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;
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;
}
/** Decode 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_fmt(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)
}
// update CRC
if (sconf->crc_enabled && avctx->error_recognition >= FF_ER_CAREFUL) {
int swap = HAVE_BIGENDIAN != sconf->msb_first;
if (ctx->avctx->bits_per_raw_sample == 24) {
int32_t *src = data;
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*) data;
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, data,
ctx->cur_frame_length * avctx->channels);
}
crc_source = ctx->crc_buffer;
} else {
crc_source = data;
}
ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source, size);
}
// 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");
}
}
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;
}
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;
// allocate crc buffer
if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
avctx->error_recognition >= FF_ER_CAREFUL) {
ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
ctx->cur_frame_length *
avctx->channels *
(av_get_bits_per_sample_fmt(avctx->sample_fmt) >> 3));
if (!ctx->crc_buffer) {
av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
decode_end(avctx);
return AVERROR(ENOMEM);
}
}
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 = {
"als",
AVMEDIA_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)"),
};
Reference in New Issue View Git Blame Copy Permalink