opensource/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2025-10-11 18:37:55 +08:00
Code Issues Packages Projects Releases Wiki Activity

Simplify rms()

Browse Source 
Originally committed as revision 13276 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Vitor Sessak
2008-05-24 09:19:21 +00:00
parent c2c237a0d5
commit 0853393979
1 changed files with 8 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

22
libavcodec/ra144.c
View File

@ -181,30 +181,24 @@ static void final(const short *i1, const short *i2,
static unsigned int rms(const int *data, int f) static unsigned int rms(const int *data, int f)
{ {
const int *c;
int x; int x;
unsigned int res; unsigned int res = 0x10000;
int b; int b = 0;
c = data;
b = 0;
res = 0x10000;
for (x=0; x<10; x++) { for (x=0; x<10; x++) {
res = (((0x1000000 - (*c) * (*c)) >> 12) * res) >> 12; res = (((0x1000000 - (*data) * (*data)) >> 12) * res) >> 12;
if (res == 0) if (res == 0)
return 0; return 0;
if (res <= 0x3fff) {
while (res <= 0x3fff) {
b++;
res <<= 2;
}
} else {
if (res > 0x10000) if (res > 0x10000)
return 0; /* We're screwed, might as well go out with a bang. :P */ return 0; /* We're screwed, might as well go out with a bang. :P */
while (res <= 0x3fff) {
b++;
res <<= 2;
} }
c++; data++;
} }
if (res > 0) if (res > 0)