adding HSV functions, with native bugs

2020-09-08 22:55:17 +02:00
parent 3cf887e103
commit 44165c0a03
3 changed files with 109 additions and 4 deletions
--- a/funcs/hsv.c
+++ b/funcs/hsv.c
@@ -0,0 +1,95 @@
+/*
+ *		FloatImg library
+ *		HUE - SATURATION - VALUE
+ */
+
+#include  <stdio.h>
+#include  <stdlib.h>
+#include  <string.h>
+#include  <math.h>
+#include  "../floatimg.h"
+
+extern int		verbosity;
+
+/* --------------------------------------------------------------------- */
+/*	helper functions						 */
+static float maxi3f(float a, float b, float c)
+{
+return ((a > b)? (a > c ? a : c) : (b > c ? b : c));
+}
+static float mini3f(float a, float b, float c)
+{
+return ((a < b)? (a < c ? a : c) : (b < c ? b : c));
+}
+static int pseudoeq(float a, float b)
+{
+return (fabsf(a-b)<0.00000000000001);		// UGLY HACK ???
+}
+/* --------------------------------------------------------------------- */
+/*
+ *		WARNING : ALL THIS CODE IS SHIT
+ */
+int fimg_rgb2hsv(float rgb[3], float hsv[3], float scale)
+{
+// float		h, s, v;
+float		cmin, cmax, diff;
+
+// scale input value to [0..1]
+rgb[0] /= scale; rgb[1] /= scale; rgb[2] /= scale;
+
+hsv[0] =  hsv[1] =  hsv[2] = -12345.6789;
+
+cmin = mini3f(rgb[0], rgb[1], rgb[2]);
+cmax = maxi3f(rgb[0], rgb[1], rgb[2]);
+diff = cmax - cmin;
+
+if (pseudoeq(cmax, cmin))		hsv[0] = 0.0;
+else if (pseudoeq(cmax, rgb[0]))
+	hsv[0] = fmod((60 * ((rgb[1] - rgb[2]) / diff) + 360), 360.0);
+else if (pseudoeq(cmax, rgb[1]))
+	hsv[0] = fmod((60 * ((rgb[2] - rgb[0]) / diff) + 120), 360.0);
+else if (pseudoeq(cmax, rgb[2]))
+	hsv[0] = fmod((60 * ((rgb[0] - rgb[1]) / diff) + 240), 360.0);
+
+if (pseudoeq(cmax, 0.0))	hsv[1] = 0.0;
+else				hsv[1] = (diff / cmax) / 100.0;
+
+hsv[2] = cmax * 100.0;		/* WHAT THE FUCK ? */
+
+#if DEBUG_LEVEL
+fprintf(stderr, "cmin/cmax   %f   %f\n", cmin, cmax);
+#endif
+
+return 0;
+}
+/* --------------------------------------------------------------------- */
+int fimg_essai_hsv(char *fname)
+{
+float		colors[3], values[3];
+int		foo, r, g, b;
+
+#define INC  16
+for (r=0; r<255; r+=INC) {
+ for (g=0; g<255; g+=INC) {
+  for (b=0; b<255; b+=INC) {
+
+	printf("%4d %4d %4d   ", r, g, b);
+
+	colors[0] = (float)r;
+	colors[1] = (float)g;
+	colors[2] = (float)b;
+	foo = fimg_rgb2hsv(colors, values, 255.0);
+	if (foo) {
+		exit(1);
+		}
+
+	printf("      %9.5f   %9.5f   %9.5f\n",
+			values[0], values[1], values[2]);
+
+	}
+ }
+}
+
+return -1;
+}
+/* --------------------------------------------------------------------- */