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Code Issues Releases Activity

Add simpler/cleaner/faster F32BE encoding/decoding.

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Originally committed as revision 14660 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Peter Ross 2008-08-07 09:32:10 +00:00
parent ff66caab40
commit 3ee573a300
1 changed files with 39 additions and 14 deletions
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53
libavcodec/pcm.c
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@ -160,6 +160,24 @@ static inline void encode_from16(int bps, int le, int us,
if (le) *dst -= bps - 2;
}
/**
* Write PCM samples macro
* @param type Datatype of native machine format
* @param endian bytestream_put_xxx() suffix
* @param src Source pointer (variable name)
* @param dst Destination pointer (variable name)
* @param n Total number of samples (variable name)
* @param offset Sample value offset
*/
#define ENCODE(type, endian, src, dst, n, offset) \
{ \
type *samples = src; \
for(;n>0;n--) { \
register type v = *samples++ + offset; \
bytestream_put_##endian(&dst, v); \
} \
}
static int pcm_encode_frame(AVCodecContext *avctx,
unsigned char *frame, int buf_size, void *data)
{
@ -174,14 +192,7 @@ static int pcm_encode_frame(AVCodecContext *avctx,
switch(avctx->codec->id) {
case CODEC_ID_PCM_F32BE:
{
float *fsamples = data;
for(;n>0;n--) {
float fv = *fsamples++;
bytestream_put_be32(&dst, av_flt2int(fv));
}
samples = (void*)fsamples;
}
ENCODE(int32_t, be32, samples, dst, n, 0)
break;
case CODEC_ID_PCM_S32LE:
encode_from16(4, 1, 0, &samples, &dst, n);
@ -334,6 +345,25 @@ static inline void decode_to16(int bps, int le, int us,
if (le) *src -= bps - 2;
}
/**
* Read PCM samples macro
* @param type Datatype of native machine format
* @param endian bytestream_get_xxx() endian suffix
* @param src Source pointer (variable name)
* @param dst Destination pointer (variable name)
* @param n Total number of samples (variable name)
* @param offset Sample value offset
*/
#define DECODE(type, endian, src, dst, n, offset) \
{ \
type *dst2 = (type*)dst; \
for(;n>0;n--) { \
register type v = bytestream_get_##endian(&src); \
*dst2++ = v - offset; \
} \
dst = (short*)dst2; \
}
static int pcm_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
const uint8_t *buf, int buf_size)
@ -371,13 +401,8 @@ static int pcm_decode_frame(AVCodecContext *avctx,
switch(avctx->codec->id) {
case CODEC_ID_PCM_F32BE:
{
float *fsamples = data;
for(;n>0;n--)
*fsamples++ = av_int2flt(bytestream_get_be32(&src));
samples = (void*)fsamples;
DECODE(int32_t, be32, src, samples, n, 0)
break;
}
case CODEC_ID_PCM_S32LE:
decode_to16(4, 1, 0, &src, &samples, buf_size);
break;