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path: root/apps/codecs/libffmpegFLAC/decoder.c
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Diffstat (limited to 'apps/codecs/libffmpegFLAC/decoder.c')
-rw-r--r--apps/codecs/libffmpegFLAC/decoder.c80
1 files changed, 18 insertions, 62 deletions
diff --git a/apps/codecs/libffmpegFLAC/decoder.c b/apps/codecs/libffmpegFLAC/decoder.c
index 1fafec1..2dbedf3 100644
--- a/apps/codecs/libffmpegFLAC/decoder.c
+++ b/apps/codecs/libffmpegFLAC/decoder.c
@@ -381,17 +381,13 @@ static inline int decode_subframe(FLACContext *s, int channel, int32_t* decoded)
}
static int decode_frame(FLACContext *s,
- int32_t* decoded0,
- int32_t* decoded1,
void (*yield)(void)) ICODE_ATTR_FLAC;
static int decode_frame(FLACContext *s,
- int32_t* decoded0,
- int32_t* decoded1,
void (*yield)(void))
{
int blocksize_code, sample_rate_code, sample_size_code, assignment, crc8;
int decorrelation, bps, blocksize, samplerate;
- int res;
+ int res, ch;
blocksize_code = get_bits(&s->gb, 4);
@@ -477,16 +473,10 @@ static int decode_frame(FLACContext *s,
s->bps = bps;
s->decorrelation= decorrelation;
- yield();
- /* subframes */
- if ((res=decode_subframe(s, 0, decoded0)) < 0)
- return res-100;
-
- yield();
-
- if (s->channels==2) {
- if ((res=decode_subframe(s, 1, decoded1)) < 0)
- return res-200;
+ for (ch=0; ch<s->channels; ++ch) {
+ yield();
+ if ((res=decode_subframe(s, ch, s->decoded[ch])) < 0)
+ return res-100;
}
yield();
@@ -499,8 +489,6 @@ static int decode_frame(FLACContext *s,
}
int flac_decode_frame(FLACContext *s,
- int32_t* decoded0,
- int32_t* decoded1,
uint8_t *buf, int buf_size,
void (*yield)(void))
{
@@ -516,68 +504,36 @@ int flac_decode_frame(FLACContext *s,
return -41;
}
- if ((framesize=decode_frame(s,decoded0,decoded1,yield)) < 0){
+ if ((framesize=decode_frame(s,yield)) < 0){
s->bitstream_size=0;
s->bitstream_index=0;
return framesize;
}
yield();
+
+#define DECORRELATE(left, right)\
+ for (i = 0; i < s->blocksize; i++) {\
+ int a = s->decoded[0][i];\
+ int b = s->decoded[1][i];\
+ s->decoded[0][i] = (left) << scale;\
+ s->decoded[1][i] = (right) << scale;\
+ }\
scale=FLAC_OUTPUT_DEPTH-s->bps;
switch(s->decorrelation)
{
case INDEPENDENT:
- if (s->channels==1) {;
- for (i = 0; i < s->blocksize; i++)
- {
- decoded0[i] = decoded0[i] << scale;
- }
- } else {
- for (i = 0; i < s->blocksize; i++)
- {
- decoded0[i] = decoded0[i] << scale;
- decoded1[i] = decoded1[i] << scale;
- }
- }
+ DECORRELATE(a, b) /* Always decorrelate exactly the two supported channels. */
break;
case LEFT_SIDE:
- //assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- decoded1[i] = (decoded0[i] - decoded1[i]) << scale;
- decoded0[i] = decoded0[i] << scale;
- }
+ DECORRELATE(a, a-b)
break;
case RIGHT_SIDE:
- //assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- decoded0[i] = (decoded0[i] + decoded1[i]) << scale;
- decoded1[i] = decoded1[i] << scale;
- }
+ DECORRELATE(a+b, a)
break;
case MID_SIDE:
- //assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- int mid, side;
- mid = decoded0[i];
- side = decoded1[i];
-
-#if 1 //needs to be checked but IMHO it should be binary identical
- mid -= side>>1;
- decoded0[i] = (mid + side) << scale;
- decoded1[i] = mid << scale;
-#else
-
- mid <<= 1;
- if (side & 1)
- mid++;
- decoded0[i] = ((mid + side) >> 1) << scale;
- decoded1[i] = ((mid - side) >> 1) << scale;
-#endif
- }
+ DECORRELATE( (a-=b>>1) + b, a)
break;
}