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alac: multi-channel decoding support

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Signed-off-by: Justin Ruggles <justin.ruggles@gmail.com>
This commit is contained in:
Andrew D'Addesio 2012-07-09 16:29:49 -04:00 committed by Justin Ruggles
parent 81c9e2e6d0
commit 1b3ef155d7
1 changed files with 43 additions and 18 deletions
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61
libavcodec/alac.c
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@ -45,7 +45,7 @@
* 32bit samplerate
*/
#include "libavutil/audioconvert.h"
#include "avcodec.h"
#include "get_bits.h"
#include "bytestream.h"
@ -53,7 +53,7 @@
#include "mathops.h"
#define ALAC_EXTRADATA_SIZE 36
#define MAX_CHANNELS 2
#define MAX_CHANNELS 8
typedef struct {
@ -64,9 +64,9 @@ typedef struct {
int channels;
/* buffers */
int32_t *predict_error_buffer[MAX_CHANNELS];
int32_t *output_samples_buffer[MAX_CHANNELS];
int32_t *extra_bits_buffer[MAX_CHANNELS];
int32_t *predict_error_buffer[2];
int32_t *output_samples_buffer[2];
int32_t *extra_bits_buffer[2];
uint32_t max_samples_per_frame;
uint8_t sample_size;
@ -90,6 +90,28 @@ enum RawDataBlockType {
TYPE_END
};
static const uint8_t alac_channel_layout_offsets[8][8] = {
{ 0 },
{ 0, 1 },
{ 2, 0, 1 },
{ 2, 0, 1, 3 },
{ 2, 0, 1, 3, 4 },
{ 2, 0, 1, 4, 5, 3 },
{ 2, 0, 1, 4, 5, 6, 3 },
{ 2, 6, 7, 0, 1, 4, 5, 3 }
};
static const uint16_t alac_channel_layouts[8] = {
AV_CH_LAYOUT_MONO,
AV_CH_LAYOUT_STEREO,
AV_CH_LAYOUT_SURROUND,
AV_CH_LAYOUT_4POINT0,
AV_CH_LAYOUT_5POINT0_BACK,
AV_CH_LAYOUT_5POINT1_BACK,
AV_CH_LAYOUT_6POINT1_BACK,
AV_CH_LAYOUT_7POINT1_WIDE_BACK
};
static inline unsigned int decode_scalar(GetBitContext *gb, int k,
int readsamplesize)
{
@ -249,7 +271,7 @@ static void predictor_decompress_fir_adapt(int32_t *error_buffer,
}
}
static void decorrelate_stereo(int32_t *buffer[MAX_CHANNELS],
static void decorrelate_stereo(int32_t *buffer[2],
int numsamples, uint8_t interlacing_shift,
uint8_t interlacing_leftweight)
{
@ -269,8 +291,8 @@ static void decorrelate_stereo(int32_t *buffer[MAX_CHANNELS],
}
}
static void append_extra_bits(int32_t *buffer[MAX_CHANNELS],
int32_t *extra_bits_buffer[MAX_CHANNELS],
static void append_extra_bits(int32_t *buffer[2],
int32_t *extra_bits_buffer[2],
int extra_bits, int numchannels, int numsamples)
{
int i, ch;
@ -326,7 +348,7 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
}
if (alac->sample_size > 16) {
for (ch = 0; ch < channels; ch++)
alac->output_samples_buffer[ch] = (int32_t *)alac->frame.data[ch_index + ch];
alac->output_samples_buffer[ch] = (int32_t *)alac->frame.extended_data[ch_index + ch];
}
} else if (output_samples != alac->nb_samples) {
av_log(avctx, AV_LOG_ERROR, "sample count mismatch: %u != %d\n",
@ -336,11 +358,11 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
alac->nb_samples = output_samples;
if (is_compressed) {
int16_t predictor_coef_table[MAX_CHANNELS][32];
int predictor_coef_num[MAX_CHANNELS];
int prediction_type[MAX_CHANNELS];
int prediction_quantitization[MAX_CHANNELS];
int ricemodifier[MAX_CHANNELS];
int16_t predictor_coef_table[2][32];
int predictor_coef_num[2];
int prediction_type[2];
int prediction_quantitization[2];
int ricemodifier[2];
interlacing_shift = get_bits(&alac->gb, 8);
interlacing_leftweight = get_bits(&alac->gb, 8);
@ -419,7 +441,7 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
switch(alac->sample_size) {
case 16: {
for (ch = 0; ch < channels; ch++) {
int16_t *outbuffer = (int16_t *)alac->frame.data[ch_index + ch];
int16_t *outbuffer = (int16_t *)alac->frame.extended_data[ch_index + ch];
for (i = 0; i < alac->nb_samples; i++)
*outbuffer++ = alac->output_samples_buffer[ch][i];
}}
@ -462,7 +484,9 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
return AVERROR_INVALIDDATA;
}
ret = decode_element(avctx, data, ch, channels);
ret = decode_element(avctx, data,
alac_channel_layout_offsets[alac->channels - 1][ch],
channels);
if (ret < 0)
return ret;
@ -484,7 +508,7 @@ static av_cold int alac_decode_close(AVCodecContext *avctx)
ALACContext *alac = avctx->priv_data;
int ch;
for (ch = 0; ch < alac->channels; ch++) {
for (ch = 0; ch < FFMIN(alac->channels, 2); ch++) {
av_freep(&alac->predict_error_buffer[ch]);
if (alac->sample_size == 16)
av_freep(&alac->output_samples_buffer[ch]);
@ -497,7 +521,7 @@ static av_cold int alac_decode_close(AVCodecContext *avctx)
static int allocate_buffers(ALACContext *alac)
{
int ch;
for (ch = 0; ch < alac->channels; ch++) {
for (ch = 0; ch < FFMIN(alac->channels, 2); ch++) {
int buf_size = alac->max_samples_per_frame * sizeof(int32_t);
FF_ALLOC_OR_GOTO(alac->avctx, alac->predict_error_buffer[ch],
@ -588,6 +612,7 @@ static av_cold int alac_decode_init(AVCodecContext * avctx)
avctx->channels);
return AVERROR_PATCHWELCOME;
}
avctx->channel_layout = alac_channel_layouts[alac->channels - 1];
if ((ret = allocate_buffers(alac)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error allocating buffers\n");