RepoMirrors/ffmpeg
1
0
Fork 0
mirror of https://git.ffmpeg.org/ffmpeg.git synced 2024-12-24 08:12:44 +00:00
Code Issues Projects Releases Wiki Activity

optimize apply_welch_window()

Browse Source 
Originally committed as revision 11881 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2008-02-09 03:42:48 +00:00
parent ead6ebdd44
commit fa4ed8c10a
1 changed files with 6 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
libavcodec/flacenc.c
View File

@ -595,11 +595,14 @@ static void apply_welch_window(const int32_t *data, int len, double *w_data)
n2 = (len >> 1);
c = 2.0 / (len - 1.0);
w_data+=n2;
data+=n2;
for(i=0; i<n2; i++) {
w = c - i - 1.0;
w = c - n2 + i;
w = 1.0 - (w * w);
w_data[i] = data[i] * w;
w_data[len-1-i] = data[len-1-i] * w;
w_data[-i-1] = data[-i-1] * w;
w_data[+i ] = data[+i ] * w;
}
}