diff --git a/Lib/falsecolors.c b/Lib/falsecolors.c
new file mode 100644
index 0000000..5453ff5
--- /dev/null
+++ b/Lib/falsecolors.c
@@ -0,0 +1,39 @@
+/*
+ *		FALSECOLORS.C
+ *
+ *	new: Wed Oct  4 07:32:36 UTC 2023
+ *
+ *	see also	calcluts.c
+ */
+
+#include  <stdio.h>
+#include  <stdlib.h>
+#include  <unistd.h>
+#include  <stdint.h>
+#include  <string.h>
+#include  <math.h>
+
+#include  "../tthimage.h"
+
+/*::------------------------------------------------------------------::*/
+/*::------------------------------------------------------------------::*/
+int Image_gen_fc_lut(float maxval, int nbslots, RGB_map *plut)
+{
+int		idx, ilut;
+float		fval;
+
+fprintf(stderr, ">>> %s ( %f %d %p )\n", __func__, maxval, nbslots, plut);
+
+/* RAZ de les luts */
+memset(plut, 0, sizeof(RGB_map));
+
+for (idx=0; idx<nbslots; idx++) {
+	fval = (float)idx / (float)nbslots;
+	ilut = (int)(fval*256.0);
+	fprintf(stderr, "    %3d   %8.6f   %3d\n", idx, fval, ilut);
+	}
+
+return FULL_NUCKED;
+}
+/*::------------------------------------------------------------------::*/
+/*::------------------------------------------------------------------::*/
diff --git a/Lib/foo.c b/Lib/foo.c
index 38e41bc..1cbfcc1 100644
--- a/Lib/foo.c
+++ b/Lib/foo.c
@@ -7,6 +7,20 @@
 #include  "../tthimage.h"
 
 /*		==============================				*/
+
+int essai_false_colors(void)
+{
+int			foo;
+RGB_map			luts;
+
+foo = Image_gen_fc_lut(27e3, 33, &luts);
+fprintf(stderr, "retour gen_fc_lut = %d\n", foo);
+
+return -1;
+}
+
+/*		==============================				*/
+
 int essai_show_t16x24( char *text)
 {
 if (NULL != text)
@@ -28,69 +42,25 @@ foo = Image_plot_V_gradient("foo.tga", 900, 200);
 fprintf(stderr, "plot v gradient -> %d\n", foo);
 }
 /*		==============================				*/
-int essai_draw_paint_rect(char *outga)
-{
-Image_Desc		*img;
-Image_Rect		rect;
-int			foo, x, y;
-
-fprintf(stderr, ">>> %s ( '%s' )\n", __func__, outga);
-
-rect.x = 8;		rect.y = 8;
-rect.w = 6;		rect.h = 6;
-
-if (NULL==(img=Image_alloc(64, 32, 3))) {
-	abort();
-	}
-
-for (x=0; x<img->width; x+=2) {
-	for (y=0; y<img->height; y+=2) {
-		Image_plotRGB(img, x, y, 200, 200, 200);
-		}
-	}
-
-foo = Image_draw_rect(img, &rect, 192, 128, 64);
-if (foo) {
-	fprintf(stderr, "%s: err %d draw rect\n", __func__, foo);
-	return foo;
-	}
-
-rect.x = 24;
-foo = Image_paint_rect(img, &rect, 64, 128, 192);
-if (foo) {
-	fprintf(stderr, "%s: err %d paint rect\n", __func__, foo);
-	return foo;
-	}
-
-foo = Image_TGA_save(outga, img, 0);
-if (foo) {
-	fprintf(stderr, "%s: err %d save '%s'\n", __func__, foo, outga);
-	return foo;
-	}
-
-return OLL_KORRECT;
-}
-/*		==============================				*/
 
 int main(int argc, char *argv[])
 {
 
 fprintf(stderr, "*** %s is running\n", argv[0]);
 
-essai_gradients();
-
-#if 0
-Image_print_version(2);
-Image_print_sizeof_structs("foo");
+if (argc > 1) {
+	fprintf(stderr, "argument: %s\n", argv[1]);
+	Image_print_version(0);
+	Image_print_sizeof_structs("foo");
+	}
+else	{
+	essai_false_colors();
+	}
 
+/*
 foo = essai_show_t16x24(NULL);
 fprintf(stderr, "essai show t16x24 --> %d\n", foo);
-
-foo = essai_draw_paint_rect("foo.tga");
-fprintf(stderr, "essai draw rect --> %d\n", foo);
-
-Image_egalise_cos01(NULL, NULL, 0);
-#endif
+*/
 
 return 0;
 }