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authorDerek Buitenhuis <derek.buitenhuis@gmail.com>2016-05-11 19:10:10 +0100
committerDerek Buitenhuis <derek.buitenhuis@gmail.com>2016-05-11 19:13:03 +0100
commit96d616052b3d39678e477fa10610ca688f46fff9 (patch)
tree8bd31d06318bc786ea8f1d84f92090c9c860bc11 /libavutil/pca-test.c
parent27506aceda8115f82f89691a4441d62a8cf24a6e (diff)
parentd12b5b2f135aade4099f4b26b0fe678656158c13 (diff)
downloadffmpeg-96d616052b3d39678e477fa10610ca688f46fff9.tar.gz
Merge commit 'd12b5b2f135aade4099f4b26b0fe678656158c13'
* commit 'd12b5b2f135aade4099f4b26b0fe678656158c13': build: Split test programs off into separate files Some conversions done by: James Almer <jamrial@gmail.com> Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Diffstat (limited to 'libavutil/pca-test.c')
-rw-r--r--libavutil/pca-test.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/libavutil/pca-test.c b/libavutil/pca-test.c
new file mode 100644
index 0000000000..e56d6185b1
--- /dev/null
+++ b/libavutil/pca-test.c
@@ -0,0 +1,102 @@
+/*
+ * principal component analysis (PCA)
+ * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "pca.c"
+#include "lfg.h"
+
+#undef printf
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void){
+ PCA *pca;
+ int i, j, k;
+#define LEN 8
+ double eigenvector[LEN*LEN];
+ double eigenvalue[LEN];
+ AVLFG prng;
+
+ av_lfg_init(&prng, 1);
+
+ pca= ff_pca_init(LEN);
+
+ for(i=0; i<9000000; i++){
+ double v[2*LEN+100];
+ double sum=0;
+ int pos = av_lfg_get(&prng) % LEN;
+ int v2 = av_lfg_get(&prng) % 101 - 50;
+ v[0] = av_lfg_get(&prng) % 101 - 50;
+ for(j=1; j<8; j++){
+ if(j<=pos) v[j]= v[0];
+ else v[j]= v2;
+ sum += v[j];
+ }
+/* for(j=0; j<LEN; j++){
+ v[j] -= v[pos];
+ }*/
+// sum += av_lfg_get(&prng) % 10;
+/* for(j=0; j<LEN; j++){
+ v[j] -= sum/LEN;
+ }*/
+// lbt1(v+100,v+100,LEN);
+ ff_pca_add(pca, v);
+ }
+
+
+ ff_pca(pca, eigenvector, eigenvalue);
+ for(i=0; i<LEN; i++){
+ pca->count= 1;
+ pca->mean[i]= 0;
+
+// (0.5^|x|)^2 = 0.5^2|x| = 0.25^|x|
+
+
+// pca.covariance[i + i*LEN]= pow(0.5, fabs
+ for(j=i; j<LEN; j++){
+ printf("%f ", pca->covariance[i + j*LEN]);
+ }
+ printf("\n");
+ }
+
+ for(i=0; i<LEN; i++){
+ double v[LEN];
+ double error=0;
+ memset(v, 0, sizeof(v));
+ for(j=0; j<LEN; j++){
+ for(k=0; k<LEN; k++){
+ v[j] += pca->covariance[FFMIN(k,j) + FFMAX(k,j)*LEN] * eigenvector[i + k*LEN];
+ }
+ v[j] /= eigenvalue[i];
+ error += fabs(v[j] - eigenvector[i + j*LEN]);
+ }
+ printf("%f ", error);
+ }
+ printf("\n");
+
+ for(i=0; i<LEN; i++){
+ for(j=0; j<LEN; j++){
+ printf("%9.6f ", eigenvector[i + j*LEN]);
+ }
+ printf(" %9.1f %f\n", eigenvalue[i], eigenvalue[i]/eigenvalue[0]);
+ }
+
+ return 0;
+}