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signed 16bit support 

Originally committed as revision 3913 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2005-02-01 01:21:32 +00:00
parent b2eef2f0ea
commit 0c90161f0f
1 changed files with 18 additions and 10 deletions
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28
tests/tiny_psnr.c
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@ -24,7 +24,7 @@
#define F 100
#define SIZE 2048
uint64_t exp16_table[20]={
uint64_t exp16_table[21]={
65537,
65538,
65540,
@ -45,6 +45,7 @@ uint64_t exp16_table[20]={
484249,
3578144,
195360063,
582360139072LL,
};
#if 1
// 16.16 fixpoint exp()
@ -60,14 +61,15 @@ static unsigned int exp16(unsigned int a){
return out;
}
// 16.16 fixpoint log()
static uint64_t log16(uint64_t a){
static int64_t log16(uint64_t a){
int i;
int out=0;
assert(a >= (1<<16));
if(a < 1<<16)
return -log16((1LL<<32) / a);
a<<=16;
for(i=19;i>=0;i--){
for(i=20;i>=0;i--){
int64_t b= exp16_table[i];
if(a<(b<<16)) continue;
out |= 1<<i;
@ -100,8 +102,10 @@ int main(int argc,char* argv[]){
FILE *f[2];
uint8_t buf[2][SIZE];
uint64_t psnr;
int len= argc<4 ? 1 : 2;
int64_t max= (1<<(8*len))-1;
if(argc!=3){
if(argc<3){
printf("tiny_psnr <file1> <file2>\n");
return -1;
}
@ -114,16 +118,20 @@ int main(int argc,char* argv[]){
if( fread(buf[1], SIZE, 1, f[1]) != 1) break;
for(j=0; j<SIZE; i++,j++){
const int a= buf[0][j];
const int b= buf[1][j];
int64_t a= buf[0][j];
int64_t b= buf[1][j];
if(len==2){
a= (int16_t)(a | (buf[0][++j]<<8));
b= (int16_t)(b | (buf[1][ j]<<8));
}
sse += (a-b) * (a-b);
}
}
if(!i) i=1;
dev= int_sqrt((sse*F*F)/i);
dev= int_sqrt( ((sse/i)*F*F) + (((sse%i)*F*F) + i/2)/i );
if(sse)
psnr= (log16(256*256*255*255LL*i/sse)*284619LL*F + (1<<31)) / (1LL<<32);
psnr= ((2*log16(max<<16) + log16(i) - log16(sse))*284619LL*F + (1<<31)) / (1LL<<32);
else
psnr= 100*F-1; //floating point free infinity :)