forked from tTh/FloatImg
92 lines
2.0 KiB
C
92 lines
2.0 KiB
C
/*
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* fimg-2gray.c
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*
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* This is a tricky job...
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <stdint.h>
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#include <unistd.h>
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#include "string.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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/*
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* floating resultat img MUST be allocated before calling this func.
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* and MUST be of type 'gray image'.
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*/
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int fimg_mk_gray_from(FloatImg *src, FloatImg *dst, int k)
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{
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float kr, kg, kb, kdiv;
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int nbb, foo;
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if (k) {
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/* some random funky values ... */
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kr = 0.789; kg = 0.523; kb = 0.349;
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}
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else {
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/* ... and canonic random values */
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kr = kg = kb = 1.0;
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}
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kdiv = kr + kg + kb;
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/* we must check the validity of our parameters */
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if (FIMG_TYPE_RGB != src->type) {
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fprintf(stderr, "%s : bad src type %d on %p\n", __func__,
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src->type, src);
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return -8;
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}
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if (FIMG_TYPE_GRAY != dst->type) {
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fprintf(stderr, "%s : bad dst type %d on %p\n", __func__,
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dst->type, dst);
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/* may be we can convert dst picture on the fly ? */
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return -9;
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}
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/* entering the main processing loop */
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nbb = src->width * src->height;
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for (foo=0; foo<nbb; foo++) {
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dst->R[foo] = ( (src->R[foo] * kr) +
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(src->G[foo] * kg) +
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(src->B[foo] * kb) ) /
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kdiv;
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}
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return 0;
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}
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/* --------------------------------------------------------------------- */
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/* this function can work 'in place' */
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int fimg_desaturate(FloatImg *src, FloatImg *dst, int notused)
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{
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int foo, nbb;
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/* we must check the validity of our parameters */
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if (notused) {
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fprintf(stderr, "notused was %d, must be 0 in %s\n",
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notused, __func__);
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}
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if (FIMG_TYPE_RGB != src->type || FIMG_TYPE_RGB != dst->type) {
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fprintf(stderr, "%s : bad image type\n", __func__);
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return -18;
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}
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/* entering the main processing loop */
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nbb = src->width * src->height;
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for (foo=0; foo<nbb; foo++) {
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dst->R[foo] = dst->G[foo] = dst->B[foo] =
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(src->R[foo] + src->G[foo] + src->B[foo]) / 3.0;
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}
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return 0;
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}
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/* --------------------------------------------------------------------- */
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