diff --git a/Fonderie/crapulator.c b/Fonderie/crapulator.c
index 1d32ed7..f54d9db 100644
--- a/Fonderie/crapulator.c
+++ b/Fonderie/crapulator.c
@@ -356,7 +356,7 @@ switch (idFx) {
 		retval = des_bords_sombres_a(image, 160);
 		break;
 	case CR_bsombrb:			/* experiment ! */
-		retval = des_bords_sombres_b(image, 100);
+		retval = des_bords_sombres_b(image, 120);
 		break;
 
 	case CR_vsglitch:
diff --git a/Fonderie/sfx.c b/Fonderie/sfx.c
index cff425f..16112b0 100644
--- a/Fonderie/sfx.c
+++ b/Fonderie/sfx.c
@@ -53,17 +53,29 @@ return -1;
 static int pixel_trinitron(FloatImg *pimg, int pos[4], float *fvals)
 {
 int		x, y, pline, off;
+int		ym;
 
 fimg_clear_rectangle(pimg, pos);
 
-for (y=pos[1]; y<pos[1]+pos[3]; y++) {
+ym = pos[1]+pos[3]-1;
+
+#define  FDIM  0.60
+
+for (y=pos[1]; y<ym; y++) {
 	pline = y*pimg->width;
-	for (x=pos[0]+2; x<(pos[0]+pos[2]-2); x++) {
-		off = pline + x;
+	for (x=0; x<5; x++) {
+		off = pline + (x+pos[0]);
 		/* wtf i'm doing here ? */
-		pimg->R[off] = fvals[0];
-		pimg->G[off] = fvals[1];
-		pimg->B[off] = fvals[2];
+		if ( (pos[1]==y) || (ym-1==y) ) {
+			pimg->R[off]    = fvals[0] * FDIM;
+			pimg->G[off+5]  = fvals[1] * FDIM;
+			pimg->B[off+10] = fvals[2] * FDIM;
+			}
+		else	{
+			pimg->R[off]    = fvals[0];
+			pimg->G[off+5]  = fvals[1];
+			pimg->B[off+10] = fvals[2];
+			}
 		}
 	}
 return 0;
diff --git a/experiment/cachengn.c b/experiment/cachengn.c
index ccfc30d..3a1f67b 100644
--- a/experiment/cachengn.c
+++ b/experiment/cachengn.c
@@ -16,3 +16,10 @@ printf("this is the version ZERO !!!\n");
 }
 
 /* ------------------------------------------------------------ */
+int init_empty_cache(int iw, int ih, int szc, int nbre)
+{
+return -1;
+}
+
+/* ------------------------------------------------------------ */
+/* ------------------------------------------------------------ */
diff --git a/experiment/cachengn.h b/experiment/cachengn.h
index e8186e9..6136ee0 100644
--- a/experiment/cachengn.h
+++ b/experiment/cachengn.h
@@ -3,3 +3,5 @@
  */
 
 void cachengn_print_version(int k);
+
+int init_empty_cache(int iw, int ih, int szc, int nbre);
diff --git a/experiment/tcache.c b/experiment/tcache.c
index 70596c1..5a8880b 100644
--- a/experiment/tcache.c
+++ b/experiment/tcache.c
@@ -6,11 +6,21 @@
 
 #include  "cachengn.h"
 
+#define IMGW	320
+#define IMGH	240
+#define SIZE	20
+#define NBRI	1000
+
 /* ------------------------------------------------------------ */
 int main(int argc, char *argv[])
 {
+int		foo;
 
 fprintf(stderr, "Test of the cache engin - %s %s\n", __DATE__, __TIME__);
+cachengn_print_version(1);
+
+foo = init_empty_cache(IMGW, IMGH, SIZE, NBRI);
+fprintf(stderr, "init_empty_cache --> %d\n", foo);
 
 return 0;
 }
diff --git a/funcs/filtrage.c b/funcs/filtrage.c
index 6b385ac..28b5506 100644
--- a/funcs/filtrage.c
+++ b/funcs/filtrage.c
@@ -10,6 +10,34 @@
 
 #include  "../floatimg.h"
 
+extern int		verbosity;
+
+/* -------------------------------------------------------------------- */
+int fimg_show_filter(char *title, FimgFilter3x3 *filtr)
+{
+float		*M;			/* alias of filter matrix */
+int		foo, idx;
+float		sum, value;
+
+if (title)	fprintf(stderr, "--------- %s ---------\n", title);
+
+M = filtr->matrix;			/* aliasing here */
+
+fprintf(stderr, "%8.3f   %8.3f   %8.3f\n", M[0], M[1], M[2]);
+fprintf(stderr, "%8.3f   %8.3f   %8.3f\n", M[3], M[4], M[5]);
+fprintf(stderr, "%8.3f   %8.3f   %8.3f\n", M[6], M[7], M[8]);
+
+sum = 0.0;
+for (idx=0; idx<9; idx++)	sum += M[idx];
+fprintf(stderr, "     sum  %8.3f\n", sum);
+fprintf(stderr, "    mult  %8.3f\n", filtr->mult);
+fprintf(stderr, "  offset  %8.3f\n", filtr->offset);
+
+value = (sum * filtr->mult) + filtr->offset;
+fprintf(stderr, "   value  %8.3f   ???\n", sum);
+
+return 0;
+}
 /* -------------------------------------------------------------------- */
 int fimg_filter_3x3(FloatImg *src, FloatImg *dst, FimgFilter3x3 *filtr)
 {
@@ -35,6 +63,10 @@ if (fimg_images_not_compatible(src, dst)) {
 	return -98;
 	}
 
+if (verbosity) {
+	fimg_show_filter("essai", filtr);
+	}
+
 /*	aliasing some vars for cleaner code */
 pr = src->R;	pg = src->G;	pb = src->B;
 w = src->width;	h = src->height;
diff --git a/funcs/fimg-dicom.c b/funcs/fimg-dicom.c
new file mode 100644
index 0000000..e69de29
diff --git a/funcs/hsv.c b/funcs/hsv.c
index d2b24f2..0786858 100644
--- a/funcs/hsv.c
+++ b/funcs/hsv.c
@@ -17,6 +17,12 @@
 
 extern int		verbosity;
 
+/*
+     https://baillehachepascal.dev/2021/rgb_hsv.php
+
+
+
+*/
 /* --------------------------------------------------------------------- */
 /*	helper functions						 */
 static float maxi3f(float a, float b, float c)
@@ -29,7 +35,7 @@ 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 ???
+return (fabsf(a-b)<0.00000001);			// UGLY HACK ???
 }
 /* --------------------------------------------------------------------- */
 /*
diff --git a/funcs/t.c b/funcs/t.c
index 3734eb7..eec87a3 100644
--- a/funcs/t.c
+++ b/funcs/t.c
@@ -24,7 +24,8 @@ enum nCmd { Equalize=1, Rotate, Sfx0, F3x3, MIRE, Wfits, Wpng, Wtiff,
 			Histo, Hsv, Classif, Ctr2x2, Qsortrgb,
 			Displace, ReadPNG, Plasmas, Hilight, OpenEXR,
 			Geometrie, FileType, Mirror, KillRGB,
-			Pixelize,SplitLevel,DecompRgbz, Rectangle  };
+			Pixelize,SplitLevel, DecompRgbz, DecompRgbg,
+			Rectangle  };
 typedef struct {
 	char	*name;
 	int	Cmd;
@@ -56,6 +57,7 @@ Command commands[] = {
 	{ "pixelize",	Pixelize	},
 	{ "spltlvl",	SplitLevel	},
 	{ "decomprgbz",	DecompRgbz	},
+	{ "decomprgbg",	DecompRgbg	},
 	{ "rectangle",  Rectangle	},
 	{ NULL,		0		}
 	} ;
@@ -234,6 +236,9 @@ switch(opt) {
 	case DecompRgbz:
 		foo = essai_decomprgb_color(filename, outfile);
 		break;
+	case DecompRgbg:
+		foo = essai_decomprgb_gray(filename, outfile);
+		break;
 	case Rectangle:
 		essai_rectangle(outfile, 0);
 		break;
diff --git a/funcs/tests.c b/funcs/tests.c
index ec0ee73..3ddf1da 100644
--- a/funcs/tests.c
+++ b/funcs/tests.c
@@ -74,6 +74,38 @@ if (foo) {
 return 0;
 }
 /* --------------------------------------------------------------------- */
+int essai_decomprgb_gray(char *inf, char *outf)
+{
+int		foo;
+FloatImg	src, dst;
+
+fprintf(stderr, ">>> %s ( %s %s )\n", __func__, inf, outf);
+
+foo = fimg_create_from_dump(inf, &src);
+if (0 != foo) {
+	fprintf(stderr, "%s: err %d loading image '%s'\n", __func__,
+				foo, 		inf);
+	return foo;
+	}
+fimg_clone(&src, &dst, 1);
+
+foo = fimg_decomp_rgbz_gray(&src, &dst, 0);
+if (foo) {
+	fprintf(stderr, "%s:%s(): fail %d line %d\n",
+			__FILE__, __func__, foo, __LINE__);
+	return foo;
+	}
+
+foo = fimg_export_picture(&dst, outf, 0);
+if (foo) {
+	fprintf(stderr, "%s : err %d saving result\n", __func__, foo);
+	return foo;
+	}
+
+fimg_destroy(&src);   fimg_destroy(&dst);
+
+return 0;
+}
 /* --------------------------------------------------------------------- */
 int essai_decomprgb_color(char *inf, char *outf)
 {
diff --git a/funcs/tests.h b/funcs/tests.h
index a4c5a09..ad4d10a 100644
--- a/funcs/tests.h
+++ b/funcs/tests.h
@@ -7,6 +7,7 @@ int essai_plasma(char *infile, char *outfile, int ikoef, float fkoef);
 int essai_miroir(char *inf, char *outf, int flags);
 int essai_killrgb(char *inf, char *outf);
 int essai_decomprgb_color(char *inf, char *outf);
+int essai_decomprgb_gray(char *inf, char *outf);
 int essai_split_level(char *inf, char *outf, int flags);
 
 int essai_displacement(char *infile, char *outfile);
diff --git a/tools/fimgfx.c b/tools/fimgfx.c
index 0fc8084..93d37cf 100644
--- a/tools/fimgfx.c
+++ b/tools/fimgfx.c
@@ -28,7 +28,7 @@ enum fxid { Fx_cos01=5, Fx_cos010, Fx_pow2, Fx_sqrt, Fx_gray0, Fx_halfsz0,
 		Fx_rot90, Fx_cmixa, Fx_desat, Fx_ctr2x2, Fx_norm,
 		Fx_classtrial, Fx_mirror, Fx_shift0, Fx_trimul,
 		Fx_xper, Fx_binarize, Fx_trinarize, Fx_hilight_R,
-		Fx_absolute };
+		Fx_absolute, Fx_clamp };
 
 Fx fx_list[] = {
 	{ "cos01",		Fx_cos01,	0,	1 },
@@ -51,6 +51,7 @@ Fx fx_list[] = {
 	{ "trinarize",		Fx_trinarize,	0,	1 },
 	{ "hilightr",		Fx_hilight_R,	0,	1 },
 	{ "abs",		Fx_absolute,	0,	1 },
+	{ "clamp",		Fx_clamp,	0,	1 },
 	{ NULL,			0,		0,	0 }
 	};
 
@@ -237,6 +238,13 @@ switch (action) {
 		fimg_copy_data(&src, &dest);
 		foo = fimg_absolute(&dest);
 								break;
+	case Fx_clamp:
+		fimg_copy_data(&src, &dest);
+		foo = fimg_clamp_negativ(&dest);
+			/* this func return the count of
+			   negative pixels killed */
+		if (foo > 0)	foo = 0;
+								break;
 	default:
 		fprintf(stderr, "%s %s : %d is bad action\n",
 					__FILE__, __func__, action);
@@ -298,7 +306,7 @@ if (action < 0) {
 	exit(1);
 	}
 
-if (verbosity) {
+if (verbosity > 1) {
 	fprintf(stderr, "  global fvalue  %f\n", global_fvalue);
 	fprintf(stderr, "  action         %d\n", action);
 	fprintf(stderr, "  verbosity      %d\n", verbosity);
@@ -310,7 +318,7 @@ if ((nba=fx_list[action].nbarg)) {
 
 srcname = argv[optind+1];
 dstname = argv[optind+2];
-if (verbosity) fprintf(stderr, "%s  ==>  %s\n", srcname, dstname);
+if (verbosity > 1) fprintf(stderr, "Fx %s  ==>  %s\n", srcname, dstname);
 
 foo = do_an_effect(srcname, action, dstname);
 if (foo) {