diff --git a/floatimg.h b/floatimg.h
index da8639b..7d207b9 100644
--- a/floatimg.h
+++ b/floatimg.h
@@ -4,7 +4,7 @@
  *	http://la.buvette.org/photos/cumul
  */
 
-#define		FIMG_VERSION	152
+#define		FIMG_VERSION	153
 
 /*
  *	in memory descriptor
@@ -124,7 +124,7 @@ int fimg_binarize(FloatImg *pimg, int notused);
 int fimg_trinarize(FloatImg *pimg, int notused);
 
 /*	 module sfx3.c			*/
-
+int fimg_crump_hard(FloatImg *src, FloatImg *dst, float kval, int notused);
 
 /*	 module sfx4.c			*/
 int fimg_sfx_triplemul(FloatImg *s, FloatImg *d, int notused);
diff --git a/funcs/Makefile b/funcs/Makefile
index 5e2b2dd..2a0d439 100644
--- a/funcs/Makefile
+++ b/funcs/Makefile
@@ -7,7 +7,8 @@ COPT = -Wall -fpic -g -no-pie  -DDEBUG_LEVEL=0
 DEPS = ../floatimg.h Makefile
 
 OBJS = fimg-png.o fimg-tiff.o misc-plots.o filtrage.o utils.o	\
-	fimg-libpnm.o rampes.o sfx0.o sfx1.o sfx2.o sfx4.o	\
+	fimg-libpnm.o rampes.o 					\
+	sfx0.o sfx1.o sfx2.o sfx3.o sfx4.o			\
 	geometry.o rotate.o fimg-openexr.o			\
 	equalize.o fimg-fits.o saturation.o histogram.o		\
 	hsv.o classif.o contour2x2.o qsortrgb.o exporter.o	\
@@ -99,6 +100,9 @@ sfx1.o:			sfx1.c $(DEPS)
 sfx2.o:			sfx2.c $(DEPS)
 	gcc $(COPT) -c $<
 
+sfx3.o:			sfx3.c $(DEPS)
+	gcc $(COPT) -c $<
+
 sfx4.o:			sfx4.c $(DEPS)
 	gcc $(COPT) -c $<
 
diff --git a/funcs/sfx3.c b/funcs/sfx3.c
new file mode 100644
index 0000000..31ebd90
--- /dev/null
+++ b/funcs/sfx3.c
@@ -0,0 +1,52 @@
+/*
+ *		FLOATIMG - a kluge from tTh
+ *		---------------------------
+ *
+ *	some strange effects on floating pictures, made in
+ *	the batcave of "Le Bib", in Montpellier.
+ */
+
+
+#include  <stdio.h>
+#include  <string.h>
+#include  <stdint.h>
+
+#include  "../floatimg.h"
+
+extern int		verbosity;
+
+/* -------------------------------------------------------------- */
+int fimg_crump_hard(FloatImg *src, FloatImg *dst, float kval, int notused)
+{
+float		halfval;
+float		rgb[3];
+int		x, y, foo;
+
+#if DEBUG_LEVEL
+fprintf(stderr, ">>> %s ( %p %p %f 0x%04x )\n", __func__,
+				src, dst, kval, notused);
+#endif
+
+halfval = fimg_get_maxvalue(src) / 2.0;
+if (verbosity) {
+	fprintf(stderr, "%s: halfval=%f\n", __func__, halfval);
+	}
+
+for (y=0; y<src->height; y++) {
+	for (x=0; x<src->width; x++) {
+		foo =  fimg_get_rgb(src, x, y, rgb);
+		if (foo)	return foo;
+
+		if (rgb[0] > halfval)		rgb[0] /= 2.0;
+		if (rgb[1] > halfval)		rgb[1] /= 2.0;
+		if (rgb[2] > halfval)		rgb[2] /= 2.0;
+
+		foo =  fimg_put_rgb(dst, x, y, rgb);
+		if (foo)	return foo;
+		}
+	}
+
+return 0;
+}
+/* -------------------------------------------------------------- */
+
diff --git a/funcs/sfx4.c b/funcs/sfx4.c
index 8366167..717b15f 100644
--- a/funcs/sfx4.c
+++ b/funcs/sfx4.c
@@ -21,7 +21,7 @@ int		x, y, foo;
 float		in[3], out[3];
 
 #if DEBUG_LEVEL
-fprintf(stderr, ">>> %s ( %p 0x%04x )\n", __func__, img, notused);
+fprintf(stderr, ">>> %s ( %p %p 0x%04x )\n", __func__, src, dst, notused);
 #endif
 
 for (y=0; y<src->height; y++) {
diff --git a/tools/fimgfx.c b/tools/fimgfx.c
index 974facb..41cf254 100644
--- a/tools/fimgfx.c
+++ b/tools/fimgfx.c
@@ -93,9 +93,9 @@ int		foo;
 fprintf(stderr, ">>> %s ( %p %p %f )\n", __func__, S, D, kf);
 #endif
 
-foo = fimg_classif_trial(S, D, kf, 0);
+foo = fimg_crump_hard(S, D, kf, 0);
 if (foo) {
-	fprintf(stderr, "%s error %d classif_trial %p\n", __func__,
+	fprintf(stderr, "%s error %d experiment %p\n", __func__,
 				foo, 		S);
 	return -98;
 	}