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atrac3: decode mono directly to the output buffer

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This commit is contained in:
Justin Ruggles
2011-10-14 16:32:55 -04:00
parent c4a6fde33f
commit 8af33cb38a
1 changed files with 11 additions and 14 deletions
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25
libavcodec/atrac3.c
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@@ -719,7 +719,8 @@ static int decodeChannelSoundUnit (ATRAC3Context *q, GetBitContext *gb, channel_
* @param databuf the input data * @param databuf the input data
*/ */
static int decodeFrame(ATRAC3Context *q, const uint8_t* databuf) static int decodeFrame(ATRAC3Context *q, const uint8_t* databuf,
float *out_samples)
{ {
int result, i; int result, i;
float *p1, *p2, *p3, *p4; float *p1, *p2, *p3, *p4;
@@ -731,7 +732,7 @@ static int decodeFrame(ATRAC3Context *q, const uint8_t* databuf)
/* decode Sound Unit 1 */ /* decode Sound Unit 1 */
init_get_bits(&q->gb,databuf,q->bits_per_frame); init_get_bits(&q->gb,databuf,q->bits_per_frame);
result = decodeChannelSoundUnit(q,&q->gb, q->pUnits, q->outSamples, 0, JOINT_STEREO); result = decodeChannelSoundUnit(q,&q->gb, q->pUnits, out_samples, 0, JOINT_STEREO);
if (result != 0) if (result != 0)
return (result); return (result);
@@ -772,14 +773,14 @@ static int decodeFrame(ATRAC3Context *q, const uint8_t* databuf)
} }
/* Decode Sound Unit 2. */ /* Decode Sound Unit 2. */
result = decodeChannelSoundUnit(q,&q->gb, &q->pUnits[1], &q->outSamples[1024], 1, JOINT_STEREO); result = decodeChannelSoundUnit(q,&q->gb, &q->pUnits[1], &out_samples[1024], 1, JOINT_STEREO);
if (result != 0) if (result != 0)
return (result); return (result);
/* Reconstruct the channel coefficients. */ /* Reconstruct the channel coefficients. */
reverseMatrixing(q->outSamples, &q->outSamples[1024], q->matrix_coeff_index_prev, q->matrix_coeff_index_now); reverseMatrixing(out_samples, &out_samples[1024], q->matrix_coeff_index_prev, q->matrix_coeff_index_now);
channelWeighting(q->outSamples, &q->outSamples[1024], q->weighting_delay); channelWeighting(out_samples, &out_samples[1024], q->weighting_delay);
} else { } else {
/* normal stereo mode or mono */ /* normal stereo mode or mono */
@@ -789,14 +790,14 @@ static int decodeFrame(ATRAC3Context *q, const uint8_t* databuf)
/* Set the bitstream reader at the start of a channel sound unit. */ /* Set the bitstream reader at the start of a channel sound unit. */
init_get_bits(&q->gb, databuf+((i*q->bytes_per_frame)/q->channels), (q->bits_per_frame)/q->channels); init_get_bits(&q->gb, databuf+((i*q->bytes_per_frame)/q->channels), (q->bits_per_frame)/q->channels);
result = decodeChannelSoundUnit(q,&q->gb, &q->pUnits[i], &q->outSamples[i*1024], i, q->codingMode); result = decodeChannelSoundUnit(q,&q->gb, &q->pUnits[i], &out_samples[i*1024], i, q->codingMode);
if (result != 0) if (result != 0)
return (result); return (result);
} }
} }
/* Apply the iQMF synthesis filter. */ /* Apply the iQMF synthesis filter. */
p1= q->outSamples; p1 = out_samples;
for (i=0 ; i<q->channels ; i++) { for (i=0 ; i<q->channels ; i++) {
p2= p1+256; p2= p1+256;
p3= p2+256; p3= p2+256;
@@ -842,19 +843,15 @@ static int atrac3_decode_frame(AVCodecContext *avctx,
databuf = buf; databuf = buf;
} }
result = decodeFrame(q, databuf); result = decodeFrame(q, databuf, q->channels == 2 ? q->outSamples : samples);
if (result != 0) { if (result != 0) {
av_log(NULL,AV_LOG_ERROR,"Frame decoding error!\n"); av_log(NULL,AV_LOG_ERROR,"Frame decoding error!\n");
return -1; return -1;
} }
if (q->channels == 1) { /* interleave */
/* mono */ if (q->channels == 2) {
for (i = 0; i<1024; i++)
samples[i] = q->outSamples[i];
} else {
/* stereo */
for (i = 0; i < 1024; i++) { for (i = 0; i < 1024; i++) {
samples[i*2] = q->outSamples[i]; samples[i*2] = q->outSamples[i];
samples[i*2+1] = q->outSamples[1024+i]; samples[i*2+1] = q->outSamples[1024+i];