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Diffstat (limited to 'src/libffmpeg/libavutil/lls.c')
| -rw-r--r-- | src/libffmpeg/libavutil/lls.c | 151 |
1 files changed, 0 insertions, 151 deletions
diff --git a/src/libffmpeg/libavutil/lls.c b/src/libffmpeg/libavutil/lls.c deleted file mode 100644 index aa9467dce..000000000 --- a/src/libffmpeg/libavutil/lls.c +++ /dev/null @@ -1,151 +0,0 @@ -/* - * linear least squares model - * - * Copyright (c) 2006 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 St, Fifth Floor, Boston, MA 02110-1301 USA - */ - -/** - * @file lls.c - * linear least squares model - */ - -#include <math.h> -#include <string.h> - -#include "lls.h" - -#ifdef TEST -#define av_log(a,b,...) printf(__VA_ARGS__) -#endif - -void av_init_lls(LLSModel *m, int indep_count){ - memset(m, 0, sizeof(LLSModel)); - - m->indep_count= indep_count; -} - -void av_update_lls(LLSModel *m, double *var, double decay){ - int i,j; - - for(i=0; i<=m->indep_count; i++){ - for(j=i; j<=m->indep_count; j++){ - m->covariance[i][j] *= decay; - m->covariance[i][j] += var[i]*var[j]; - } - } -} - -void av_solve_lls(LLSModel *m, double threshold, int min_order){ - int i,j,k; - double (*factor)[MAX_VARS+1]= &m->covariance[1][0]; - double (*covar )[MAX_VARS+1]= &m->covariance[1][1]; - double *covar_y = m->covariance[0]; - int count= m->indep_count; - - for(i=0; i<count; i++){ - for(j=i; j<count; j++){ - double sum= covar[i][j]; - - for(k=i-1; k>=0; k--) - sum -= factor[i][k]*factor[j][k]; - - if(i==j){ - if(sum < threshold) - sum= 1.0; - factor[i][i]= sqrt(sum); - }else - factor[j][i]= sum / factor[i][i]; - } - } - for(i=0; i<count; i++){ - double sum= covar_y[i+1]; - for(k=i-1; k>=0; k--) - sum -= factor[i][k]*m->coeff[0][k]; - m->coeff[0][i]= sum / factor[i][i]; - } - - for(j=count-1; j>=min_order; j--){ - for(i=j; i>=0; i--){ - double sum= m->coeff[0][i]; - for(k=i+1; k<=j; k++) - sum -= factor[k][i]*m->coeff[j][k]; - m->coeff[j][i]= sum / factor[i][i]; - } - - m->variance[j]= covar_y[0]; - for(i=0; i<=j; i++){ - double sum= m->coeff[j][i]*covar[i][i] - 2*covar_y[i+1]; - for(k=0; k<i; k++) - sum += 2*m->coeff[j][k]*covar[k][i]; - m->variance[j] += m->coeff[j][i]*sum; - } - } -} - -double av_evaluate_lls(LLSModel *m, double *param, int order){ - int i; - double out= 0; - - for(i=0; i<=order; i++) - out+= param[i]*m->coeff[order][i]; - - return out; -} - -#ifdef TEST - -#include <stdlib.h> -#include <stdio.h> - -int main(){ - LLSModel m; - int i, order; - - av_init_lls(&m, 3); - - for(i=0; i<100; i++){ - double var[4]; - double eval, variance; -#if 0 - var[1] = rand() / (double)RAND_MAX; - var[2] = rand() / (double)RAND_MAX; - var[3] = rand() / (double)RAND_MAX; - - var[2]= var[1] + var[3]/2; - - var[0] = var[1] + var[2] + var[3] + var[1]*var[2]/100; -#else - var[0] = (rand() / (double)RAND_MAX - 0.5)*2; - var[1] = var[0] + rand() / (double)RAND_MAX - 0.5; - var[2] = var[1] + rand() / (double)RAND_MAX - 0.5; - var[3] = var[2] + rand() / (double)RAND_MAX - 0.5; -#endif - av_update_lls(&m, var, 0.99); - av_solve_lls(&m, 0.001, 0); - for(order=0; order<3; order++){ - eval= av_evaluate_lls(&m, var+1, order); - av_log(NULL, AV_LOG_DEBUG, "real:%f order:%d pred:%f var:%f coeffs:%f %f %f\n", - var[0], order, eval, sqrt(m.variance[order] / (i+1)), - m.coeff[order][0], m.coeff[order][1], m.coeff[order][2]); - } - } - return 0; -} - -#endif |