forked from tTh/FloatImg
136 lines
2.9 KiB
C
136 lines
2.9 KiB
C
/*
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* fimg-core.c
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*
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*
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <string.h>
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#include <math.h>
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#include "../floatimg.h"
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extern int verbosity; /* must be declared around main() */
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/* ---------------------------------------------------------------- */
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float fimg_get_maxvalue(FloatImg *head)
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{
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float maxval;
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int foo;
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if (head->type != FIMG_TYPE_RGB && head->type != FIMG_TYPE_GRAY) {
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fprintf(stderr, "%s : type %d invalide\n",
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__func__, head->type);
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return nanf("wtf ?");
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}
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maxval = 0.0; /* no negative values allowed */
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switch (head->type) {
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case FIMG_TYPE_RGB:
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for (foo=0; foo<(head->width*head->height); foo++) {
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if (head->R[foo] > maxval) maxval = head->R[foo];
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if (head->G[foo] > maxval) maxval = head->G[foo];
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if (head->B[foo] > maxval) maxval = head->B[foo];
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}
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case FIMG_TYPE_GRAY:
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for (foo=0; foo<(head->width*head->height); foo++) {
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if (head->R[foo] > maxval) maxval = head->R[foo];
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}
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}
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return maxval;
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}
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/* ---------------------------------------------------------------- */
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int fimg_meanvalues(FloatImg *head, float means[4])
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{
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int idx, surface;
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surface = head->width * head->height;
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if (surface < 1) return -1;
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memset(means, 0, 4*sizeof(float));
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for (idx=0; idx<surface; idx++) {
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means[0] += head->R[idx];
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if (head->type > 2) {
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means[1] += head->G[idx];
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means[2] += head->B[idx];
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}
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}
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for (idx=0; idx<4; idx++) means[idx] /= (float)surface;
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return 0;
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}
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/* ---------------------------------------------------------------- */
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/*
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* more elaborate functions are in fimg-2gray.c
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*/
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int fimg_to_gray(FloatImg *head)
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{
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float add;
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int foo;
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if (head->type != FIMG_TYPE_RGB) {
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fprintf(stderr, "%s : type %d invalide\n",
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__func__, head->type);
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return -3;
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}
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for (foo=0; foo<(head->width*head->height); foo++) {
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add = head->R[foo];
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add += head->G[foo];
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add += head->B[foo];
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head->R[foo] = head->G[foo] = head->B[foo] = add;
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}
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return -1;
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}
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/* ---------------------------------------------------------------- */
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void fimg_add_cste(FloatImg *fi, float value)
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{
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int nbre, idx;
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if (fi->type != FIMG_TYPE_RGB) {
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fprintf(stderr, "%s : type %d invalide\n",
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__func__, fi->type);
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return;
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}
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nbre = fi->width * fi->height * fi->type;
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#if DEBUG_LEVEL
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fprintf(stderr, "%s, nbre is %d\n", __func__, nbre);
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#endif
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for (idx=0; idx<nbre; nbre++) {
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fi->R[idx] += value;
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}
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}
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/* ---------------------------------------------------------------- */
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/* Warning: this function is _very_ slow */
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void fimg_drand48(FloatImg *fi, float kmul)
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{
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int nbre, idx;
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#if DEBUG_LEVEL
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fprintf(stderr, ">>> %s ( %p %g )\n", __func__, fi, kmul);
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#endif
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if (fi->type != FIMG_TYPE_RGB) {
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fprintf(stderr, "%s : type %d invalide\n",
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__func__, fi->type);
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return;
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}
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nbre = fi->width * fi->height;
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for (idx=0; idx<nbre; idx++) {
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fi->R[idx] = drand48() * kmul;
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fi->G[idx] = drand48() * kmul;
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fi->B[idx] = drand48() * kmul;
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}
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}
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/* ---------------------------------------------------------------- */
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