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authorChristophe GISQUET <christophe.gisquet@gmail.com>2012-04-17 18:44:43 +0000
committerRonald S. Bultje <rsbultje@gmail.com>2012-04-28 11:16:07 -0700
commit7fb8b491e5c10b3fbad53ffc89c60d3541114416 (patch)
tree559e68d863066edd073a10101f386c22bdd683f6 /libavcodec/rv34dsp.c
parentd834ab0f2a5d5689cdd323e935534fda918319ef (diff)
downloadffmpeg-7fb8b491e5c10b3fbad53ffc89c60d3541114416.tar.gz
rv34dsp: factorize a multiplication in the noround inverse transform
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
Diffstat (limited to 'libavcodec/rv34dsp.c')
-rw-r--r--libavcodec/rv34dsp.c18
1 files changed, 9 insertions, 9 deletions
diff --git a/libavcodec/rv34dsp.c b/libavcodec/rv34dsp.c
index 4145c4dd85..1ddcea4c0f 100644
--- a/libavcodec/rv34dsp.c
+++ b/libavcodec/rv34dsp.c
@@ -88,15 +88,15 @@ static void rv34_inv_transform_noround_c(DCTELEM *block){
rv34_row_transform(temp, block);
for(i = 0; i < 4; i++){
- const int z0 = 13*(temp[4*0+i] + temp[4*2+i]);
- const int z1 = 13*(temp[4*0+i] - temp[4*2+i]);
- const int z2 = 7* temp[4*1+i] - 17*temp[4*3+i];
- const int z3 = 17* temp[4*1+i] + 7*temp[4*3+i];
-
- block[i*4+0] = ((z0 + z3) * 3) >> 11;
- block[i*4+1] = ((z1 + z2) * 3) >> 11;
- block[i*4+2] = ((z1 - z2) * 3) >> 11;
- block[i*4+3] = ((z0 - z3) * 3) >> 11;
+ const int z0 = 39*(temp[4*0+i] + temp[4*2+i]);
+ const int z1 = 39*(temp[4*0+i] - temp[4*2+i]);
+ const int z2 = 21* temp[4*1+i] - 51*temp[4*3+i];
+ const int z3 = 51* temp[4*1+i] + 21*temp[4*3+i];
+
+ block[i*4+0] = (z0 + z3) >> 11;
+ block[i*4+1] = (z1 + z2) >> 11;
+ block[i*4+2] = (z1 - z2) >> 11;
+ block[i*4+3] = (z0 - z3) >> 11;
}
}