/* create a pyramid of color images using a given scale factor, stopping when one dimension reach min_size and with applying a gaussian smoothing of standard deviation spyr (no smoothing if 0) */
color_image_pyramid_t *color_image_pyramid_create(const color_image_t *src, const float scale_factor, const int min_size, const float spyr){
const int nb_max_scale = 1000;
// allocate structure
color_image_pyramid_t *pyramid = color_image_pyramid_new();
pyramid->min_size = min_size;
pyramid->scale_factor = scale_factor;
convolution_t *conv = NULL;
if(spyr>0.0f){
int fsize;
float *filter_coef = gaussian_filter(spyr, &fsize);
conv = convolution_new(fsize, filter_coef, 1);
free(filter_coef);
}
color_image_pyramid_set_size(pyramid, nb_max_scale);
pyramid->images[0] = color_image_cpy(src);
int i;
for( i=1 ; i<nb_max_scale ; i++){
const int oldwidth = pyramid->images[i-1]->width, oldheight = pyramid->images[i-1]->height;
const int newwidth = (int) (1.5f + (oldwidth-1) / scale_factor);
const int newheight = (int) (1.5f + (oldheight-1) / scale_factor);
if( newwidth <= min_size || newheight <= min_size){
color_image_pyramid_set_size(pyramid, i);
break;
}
if(spyr>0.0f){
color_image_t* tmp = color_image_new(oldwidth, oldheight);
color_image_convolve_hv(tmp,pyramid->images[i-1], conv, conv);
pyramid->images[i]= color_image_resize_bilinear(tmp, scale_factor);
color_image_delete(tmp);
}else{
pyramid->images[i] = color_image_resize_bilinear(pyramid->images[i-1], scale_factor);
}
}
if(spyr>0.0f){
convolution_delete(conv);
}
return pyramid;
}
float *color_gist_scaletab(color_image_t *src, int w, int n_scale, const int *n_orientation)
{
int i;
if(src->width < 8 || src->height < 8)
{
fprintf(stderr, "Error: color_gist_scaletab() - Image not big enough !\n");
return NULL;
}
int numberBlocks = w;
int tot_oris=0;
for(i=0;i<n_scale;i++) tot_oris+=n_orientation[i];
color_image_t *img = color_image_cpy(src);
image_list_t *G = create_gabor(n_scale, n_orientation, img->width, img->height);
color_prefilt(img, 4);
float *g = color_gist_gabor(img, numberBlocks, G);
for(i = 0; i < tot_oris*w*w*3; i++)
{
if(!finite(g[i]))
{
fprintf(stderr, "Error: color_gist_scaletab() - descriptor not valid (nan or inf)\n");
free(g); g=NULL;
break;
}
}
image_list_delete(G);
color_image_delete(img);
return g;
}
