*
* Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file lls.c
+ * @file
* linear least squares model
*/
#include <math.h>
#include <string.h>
+#include "version.h"
#include "lls.h"
-#ifdef TEST
-#define av_log(a,b,...) printf(__VA_ARGS__)
-#endif
-
-void av_init_lls(LLSModel *m, int indep_count){
+void avpriv_init_lls(LLSModel *m, int indep_count)
+{
memset(m, 0, sizeof(LLSModel));
-
- m->indep_count= indep_count;
+ m->indep_count = indep_count;
}
-void av_update_lls(LLSModel *m, double *var, double decay){
- int i,j;
+void avpriv_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++){
+ 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];
+ 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];
+void avpriv_solve_lls(LLSModel *m, double threshold, unsigned short min_order)
+{
+ int i, j, k;
+ double (*factor)[MAX_VARS + 1] = (void *) &m->covariance[1][0];
+ double (*covar) [MAX_VARS + 1] = (void *) &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 (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];
+ 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;
+ 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){
+double avpriv_evaluate_lls(LLSModel *m, double *param, int order)
+{
int i;
- double out= 0;
+ double out = 0;
- for(i=0; i<=order; i++)
- out+= param[i]*m->coeff[order][i];
+ for (i = 0; i <= order; i++)
+ out += param[i] * m->coeff[order][i];
return out;
}
+#if FF_API_LLS_PRIVATE
+void av_init_lls(LLSModel *m, int indep_count)
+{
+ avpriv_init_lls(m, indep_count);
+}
+void av_update_lls(LLSModel *m, double *param, double decay)
+{
+ avpriv_update_lls(m, param, decay);
+}
+void av_solve_lls(LLSModel *m, double threshold, int min_order)
+{
+ avpriv_solve_lls(m, threshold, min_order);
+}
+double av_evaluate_lls(LLSModel *m, double *param, int order)
+{
+ return avpriv_evaluate_lls(m, param, order);
+}
+#endif /* FF_API_LLS_PRIVATE */
+
#ifdef TEST
-#include <stdlib.h>
#include <stdio.h>
+#include <limits.h>
+#include "lfg.h"
-int main(void){
+int main(void)
+{
LLSModel m;
int i, order;
+ AVLFG lfg;
- av_init_lls(&m, 3);
+ av_lfg_init(&lfg, 1);
+ avpriv_init_lls(&m, 3);
- for(i=0; i<100; i++){
+ 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]);
+ double eval;
+
+ var[0] = (av_lfg_get(&lfg) / (double) UINT_MAX - 0.5) * 2;
+ var[1] = var[0] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
+ var[2] = var[1] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
+ var[3] = var[2] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
+ avpriv_update_lls(&m, var, 0.99);
+ avpriv_solve_lls(&m, 0.001, 0);
+ for (order = 0; order < 3; order++) {
+ eval = avpriv_evaluate_lls(&m, var + 1, order);
+ printf("real:%9f order:%d pred:%9f var:%f coeffs:%f %9f %9f\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;
projects / ffmpeg / blobdiff