using autoshift to zero

Fonderie/crapulator.c

@@ -126,12 +126,22 @@ if (retval) {
 	fprintf(stderr, "%s error %d on filter\n", __func__, retval);
 	exit(1);
 	}
+
+foo = fimg_auto_shift_to_zero(&img, &img);
+if (foo) {
+	fprintf(stderr, "%s: err %d zero shift\n", __func__, foo);
+	exit(1);
+	}
+
 /**	may be, we can check for negative values ? */
+/**	or is this useless because whe have shifted to zero ? */
 if (verbosity > 1) {
 	foo = fimg_count_negativ(&img);
+	if (foo) {
 		fprintf(stderr, "%s -> %d / %d negative pixels\n", __func__,
 					foo, img.width*img.height);
 		}
+	}
 
 fimg_killborders(&img);
 fimg_copy_data(&img, pimg);

floatimg.h

@@ -3,7 +3,7 @@
  *			ugly code from tTh
  */
 
-#define		FIMG_VERSION	119
+#define		FIMG_VERSION	120
 
 /*
  *	in memory descriptor
@@ -128,7 +128,10 @@ int fimg_power_2(FloatImg *s, FloatImg *d, double maxval);
 int fimg_cos_01(FloatImg *s, FloatImg *d, double maxval);
 int fimg_cos_010(FloatImg *s, FloatImg *d, double maxval);
 int fimg_mix_rgb_gray(FloatImg *img, float mix);
+
+/*	funcs/saturation.c		*/
 int     fimg_shift_to_zero(FloatImg *s, FloatImg *d, float coefs[6]);
+int     fimg_auto_shift_to_zero(FloatImg *s, FloatImg *d);
 
 /*	--> funcs/plasmas.c		*/
 int fimg_prototype_plasma(FloatImg *img, double time, int type);

funcs/saturation.c

@@ -70,5 +70,30 @@ for (idx=0; idx<sz; idx++) {
 return 0;
 }
 
-
 /* -------------------------------------------------------------- */
+int  fimg_auto_shift_to_zero(FloatImg *src, FloatImg *dst)
+{
+float		coefs[6];
+int		foo;
+
+if (FIMG_TYPE_RGB != src->type) {
+	fprintf(stderr, "%s: bad image type %d\n", __func__, src->type);
+	return -6;
+	}
+
+foo = fimg_get_minmax_rgb(src, coefs);
+if (foo) {
+	fprintf(stderr, "%s: err %d get minmax\n", __func__, foo);
+	return foo;
+	}
+
+foo = fimg_shift_to_zero(src, dst, coefs);
+if (foo) {
+	fprintf(stderr, "%s WTF?\n", __func__);
+	return foo;
+	}
+
+return 0;
+}
+/* -------------------------------------------------------------- */
+