virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
Code Issues Releases Activity

Make ff_pca_init() allocate it struct instead of letting the user provide

Browse Source 
one (more robust ABI wise).

Originally committed as revision 14807 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2008-08-17 15:46:20 +00:00
parent 7b0a6612c6
commit 6441737591
1 changed files with 14 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
libavutil/pca.c
View File

@ -26,21 +26,24 @@
#include "common.h" #include "common.h"
#include "pca.h" #include "pca.h"
int ff_pca_init(PCA *pca, int n){ PCA *ff_pca_init(int n){
PCA *pca;
if(n<=0) if(n<=0)
return -1; return NULL;
pca= av_mallocz(sizeof(PCA));
pca->n= n; pca->n= n;
pca->count=0; pca->count=0;
pca->covariance= av_mallocz(sizeof(double)*n*n); pca->covariance= av_mallocz(sizeof(double)*n*n);
pca->mean= av_mallocz(sizeof(double)*n); pca->mean= av_mallocz(sizeof(double)*n);
return 0; return pca;
} }
void ff_pca_free(PCA *pca){ void ff_pca_free(PCA *pca){
av_freep(&pca->covariance); av_freep(&pca->covariance);
av_freep(&pca->mean); av_freep(&pca->mean);
av_free(pca);
} }
void ff_pca_add(PCA *pca, double *v){ void ff_pca_add(PCA *pca, double *v){
@ -157,13 +160,13 @@ int ff_pca(PCA *pca, double *eigenvector, double *eigenvalue){
#include <stdlib.h> #include <stdlib.h>
int main(){ int main(){
PCA pca; PCA *pca;
int i, j, k; int i, j, k;
#define LEN 8 #define LEN 8
double eigenvector[LEN*LEN]; double eigenvector[LEN*LEN];
double eigenvalue[LEN]; double eigenvalue[LEN];
ff_pca_init(&pca, LEN); pca= ff_pca_init(LEN);
for(i=0; i<9000000; i++){ for(i=0; i<9000000; i++){
double v[2*LEN+100]; double v[2*LEN+100];
@ -184,21 +187,21 @@ int main(){
v[j] -= sum/LEN; v[j] -= sum/LEN;
}*/ }*/
// lbt1(v+100,v+100,LEN); // lbt1(v+100,v+100,LEN);
ff_pca_add(&pca, v); ff_pca_add(pca, v);
} }
ff_pca(&pca, eigenvector, eigenvalue); ff_pca(pca, eigenvector, eigenvalue);
for(i=0; i<LEN; i++){ for(i=0; i<LEN; i++){
pca.count= 1; pca->count= 1;
pca.mean[i]= 0; pca->mean[i]= 0;
// (0.5^|x|)^2 = 0.5^2|x| = 0.25^|x| // (0.5^|x|)^2 = 0.5^2|x| = 0.25^|x|
// pca.covariance[i + i*LEN]= pow(0.5, fabs // pca.covariance[i + i*LEN]= pow(0.5, fabs
for(j=i; j<LEN; j++){ for(j=i; j<LEN; j++){
printf("%f ", pca.covariance[i + j*LEN]); printf("%f ", pca->covariance[i + j*LEN]);
} }
printf("\n"); printf("\n");
} }
@ -210,7 +213,7 @@ int main(){
memset(v, 0, sizeof(v)); memset(v, 0, sizeof(v));
for(j=0; j<LEN; j++){ for(j=0; j<LEN; j++){
for(k=0; k<LEN; k++){ for(k=0; k<LEN; k++){
v[j] += pca.covariance[FFMIN(k,j) + FFMAX(k,j)*LEN] * eigenvector[i + k*LEN]; v[j] += pca->covariance[FFMIN(k,j) + FFMAX(k,j)*LEN] * eigenvector[i + k*LEN];
} }
v[j] /= eigenvalue[i]; v[j] /= eigenvalue[i];
error += fabs(v[j] - eigenvector[i + j*LEN]); error += fabs(v[j] - eigenvector[i + j*LEN]);