* commit 'a6a750c7ef240b72ce01e9653343a0ddf247d196': tests: Move all test programs to a subdirectory Merged-by: Clément Bœsch <clement@stupeflix.com>
		
			
				
	
	
		
			103 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			103 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * principal component analysis (PCA)
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|  * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| #include "libavutil/pca.c"
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| #include "libavutil/lfg.h"
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| 
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| #undef printf
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| #include <stdio.h>
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| #include <stdlib.h>
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| 
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| int main(void){
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|     PCA *pca;
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|     int i, j, k;
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| #define LEN 8
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|     double eigenvector[LEN*LEN];
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|     double eigenvalue[LEN];
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|     AVLFG prng;
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| 
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|     av_lfg_init(&prng, 1);
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| 
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|     pca= ff_pca_init(LEN);
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| 
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|     for(i=0; i<9000000; i++){
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|         double v[2*LEN+100];
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|         double sum=0;
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|         int pos = av_lfg_get(&prng) % LEN;
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|         int v2  = av_lfg_get(&prng) % 101 - 50;
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|         v[0]    = av_lfg_get(&prng) % 101 - 50;
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|         for(j=1; j<8; j++){
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|             if(j<=pos) v[j]= v[0];
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|             else       v[j]= v2;
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|             sum += v[j];
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|         }
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| /*        for(j=0; j<LEN; j++){
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|             v[j] -= v[pos];
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|         }*/
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| //        sum += av_lfg_get(&prng) % 10;
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| /*        for(j=0; j<LEN; j++){
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|             v[j] -= sum/LEN;
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|         }*/
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| //        lbt1(v+100,v+100,LEN);
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|         ff_pca_add(pca, v);
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|     }
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| 
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| 
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|     ff_pca(pca, eigenvector, eigenvalue);
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|     for(i=0; i<LEN; i++){
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|         pca->count= 1;
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|         pca->mean[i]= 0;
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| 
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| //        (0.5^|x|)^2 = 0.5^2|x| = 0.25^|x|
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| 
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| 
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| //        pca.covariance[i + i*LEN]= pow(0.5, fabs
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|         for(j=i; j<LEN; j++){
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|             printf("%f ", pca->covariance[i + j*LEN]);
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|         }
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|         printf("\n");
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|     }
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| 
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|     for(i=0; i<LEN; i++){
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|         double v[LEN];
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|         double error=0;
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|         memset(v, 0, sizeof(v));
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|         for(j=0; j<LEN; j++){
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|             for(k=0; k<LEN; k++){
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|                 v[j] += pca->covariance[FFMIN(k,j) + FFMAX(k,j)*LEN] * eigenvector[i + k*LEN];
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|             }
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|             v[j] /= eigenvalue[i];
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|             error += fabs(v[j] - eigenvector[i + j*LEN]);
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|         }
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|         printf("%f ", error);
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|     }
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|     printf("\n");
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| 
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|     for(i=0; i<LEN; i++){
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|         for(j=0; j<LEN; j++){
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|             printf("%9.6f ", eigenvector[i + j*LEN]);
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|         }
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|         printf("  %9.1f %f\n", eigenvalue[i], eigenvalue[i]/eigenvalue[0]);
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|     }
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| 
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|     return 0;
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| }
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