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authorVitor Sessak <vitor1001@gmail.com>2010-03-21 11:35:05 +0000
committerVitor Sessak <vitor1001@gmail.com>2010-03-21 11:35:05 +0000
commit8305c76b53d8af602fd5172a5e0ab95cd8ded566 (patch)
treeed6f3533d6cd1e75f703825bc4c4d5fbd856f755 /libavcodec
parente30ab38e94252398e4390e12e1a883d24cc5afa5 (diff)
downloadffmpeg-8305c76b53d8af602fd5172a5e0ab95cd8ded566.tar.gz
Split DCT-II and DCT-III in different functions, they do not share any code.
Originally committed as revision 22618 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec')
-rw-r--r--libavcodec/dct.c16
1 files changed, 11 insertions, 5 deletions
diff --git a/libavcodec/dct.c b/libavcodec/dct.c
index 7cc383379b..c7f5f7e180 100644
--- a/libavcodec/dct.c
+++ b/libavcodec/dct.c
@@ -37,12 +37,11 @@
/* cos((M_PI * x / (2*n)) */
#define COS(s,n,x) (s->costab[x])
-static void ff_dct_calc_c(DCTContext *ctx, FFTSample *data)
+static void ff_dct_calc_III_c(DCTContext *ctx, FFTSample *data)
{
int n = 1 << ctx->nbits;
int i;
- if (ctx->inverse) {
float next = data[n - 1];
float inv_n = 1.0f / n;
@@ -69,7 +68,12 @@ static void ff_dct_calc_c(DCTContext *ctx, FFTSample *data)
data[i ] = tmp1 + csc;
data[n - i - 1] = tmp1 - csc;
}
- } else {
+}
+
+static void ff_dct_calc_II_c(DCTContext *ctx, FFTSample *data)
+{
+ int n = 1 << ctx->nbits;
+ int i;
float next;
for (i=0; i < n/2; i++) {
float tmp1 = data[i ];
@@ -100,7 +104,6 @@ static void ff_dct_calc_c(DCTContext *ctx, FFTSample *data)
next += s * inr - c * ini;
}
- }
}
void ff_dct_calc(DCTContext *s, FFTSample *data)
@@ -130,7 +133,10 @@ av_cold int ff_dct_init(DCTContext *s, int nbits, int inverse)
for (i = 0; i < n/2; i++)
s->csc2[i] = 0.5 / sin((M_PI / (2*n) * (2*i + 1)));
- s->dct_calc = ff_dct_calc_c;
+ if(inverse) {
+ s->dct_calc = ff_dct_calc_III_c;
+ } else
+ s->dct_calc = ff_dct_calc_II_c;
return 0;
}