virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
Code Issues Releases Activity

fix 24bit flac support, revised from Thibaut Mattern <thibaut.mattern@gmail.com>

Browse Source 
Originally committed as revision 5507 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Luca Barbato 2006-06-21 00:21:26 +00:00
parent ea138e978a
commit 0187178e07
1 changed files with 39 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
libavcodec/flac.c
View File

@ -296,7 +296,7 @@ static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order)
static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
{
int sum, i, j;
int i, j;
int coeff_prec, qlevel;
int coeffs[pred_order];
@ -334,6 +334,17 @@ static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
if (decode_residuals(s, channel, pred_order) < 0)
return -1;
if (s->bps > 16) {
int64_t sum;
for (i = pred_order; i < s->blocksize; i++)
{
sum = 0;
for (j = 0; j < pred_order; j++)
sum += (int64_t)coeffs[j] * s->decoded[channel][i-j-1];
s->decoded[channel][i] += sum >> qlevel;
}
} else {
int sum;
for (i = pred_order; i < s->blocksize; i++)
{
sum = 0;
@ -341,6 +352,7 @@ static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
sum += coeffs[j] * s->decoded[channel][i-j-1];
s->decoded[channel][i] += sum >> qlevel;
}
}
return 0;
}
@ -538,6 +550,17 @@ static int decode_frame(FLACContext *s)
return 0;
}
static inline int16_t shift_to_16_bits(int32_t data, int bps)
{
if (bps == 24) {
return (data >> 8);
} else if (bps == 20) {
return (data >> 4);
} else {
return data;
}
}
static int flac_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
uint8_t *buf, int buf_size)
@ -680,23 +703,25 @@ static int flac_decode_frame(AVCodecContext *avctx,
for (j = 0; j < s->blocksize; j++)
{
for (i = 0; i < s->channels; i++)
*(samples++) = s->decoded[i][j];
*(samples++) = shift_to_16_bits(s->decoded[i][j], s->bps);
}
break;
case LEFT_SIDE:
assert(s->channels == 2);
for (i = 0; i < s->blocksize; i++)
{
*(samples++) = s->decoded[0][i];
*(samples++) = s->decoded[0][i] - s->decoded[1][i];
*(samples++) = shift_to_16_bits(s->decoded[0][i], s->bps);
*(samples++) = shift_to_16_bits(s->decoded[0][i]
- s->decoded[1][i], s->bps);
}
break;
case RIGHT_SIDE:
assert(s->channels == 2);
for (i = 0; i < s->blocksize; i++)
{
*(samples++) = s->decoded[0][i] + s->decoded[1][i];
*(samples++) = s->decoded[1][i];
*(samples++) = shift_to_16_bits(s->decoded[0][i]
+ s->decoded[1][i], s->bps);
*(samples++) = shift_to_16_bits(s->decoded[1][i], s->bps);
}
break;
case MID_SIDE:
@ -709,8 +734,8 @@ static int flac_decode_frame(AVCodecContext *avctx,
#if 1 //needs to be checked but IMHO it should be binary identical
mid -= side>>1;
*(samples++) = mid + side;
*(samples++) = mid;
*(samples++) = shift_to_16_bits(mid + side, s->bps);
*(samples++) = shift_to_16_bits(mid, s->bps);
#else
mid <<= 1;