diff --git a/funcs/vroum.sh b/funcs/vroum.sh
index 74a40c49..3ffc3135 100755
--- a/funcs/vroum.sh
+++ b/funcs/vroum.sh
@@ -1,14 +1,16 @@
 #!/bin/bash
 
-
 src=foo.fimg
-maxi=179
-grabopt=" s 320x240 -vv -p 0 -n 100 -c none "
+maxi=49
+grabopt=" -s 1280x720 -vv -p 0 -n 200 -c none "
 
+mkdir V
 
 for foo in $(seq 0 $maxi)
 do
 
+	echo
+
 	grabvidseq -$grabopt -o $src
 
 	fval=$(echo "$foo / $maxi" | bc -l)
@@ -16,11 +18,10 @@ do
 
 	echo $foo $fval
 
-	nom=$(printf "v_%03d.pnm" $foo)
+	nom=$(printf "V/%03d.pnm" $foo)
 	cp out.pnm $nom
-
 	echo $nom
 
 done
 
-convert -delay 20 v_*.pnm foo.gif
+convert -delay 20 V/*.pnm foo.gif
diff --git a/tools/essai.sh b/tools/essai.sh
index e711c631..3ecc2422 100755
--- a/tools/essai.sh
+++ b/tools/essai.sh
@@ -27,7 +27,6 @@ function essai_cmixa
 {
 ./mkfimg -vv -t tpat0 $TMPF 800 600
 ./fimgfx -vv cmixa $TMPF bar.fimg
-
 }
 #  -----------------------------------------------------
 function essai_cumulator
@@ -42,7 +41,13 @@ D=" 800 600 "
 	hdeg.fimg pat0.fimg rand.fimg vdeg.fimg
 }
 #  -----------------------------------------------------
+function essai_contour
+{
+./mkfimg -vv -t tpat0 $TMPF 800 600
+./fimgfx -vv ctr2x2 $TMPF bar.fimg
+}
+#  -----------------------------------------------------
 
-essai_cumulator
+essai_contour
 
 #  -----------------------------------------------------
diff --git a/tools/fimgfx.c b/tools/fimgfx.c
index 976f5466..53e9d905 100644
--- a/tools/fimgfx.c
+++ b/tools/fimgfx.c
@@ -21,7 +21,7 @@ typedef struct {
 	} Fx;
 
 enum fxid { Fx_cos01=5, Fx_cos010, Fx_pow2, Fx_sqrt, Fx_gray0, Fx_halfsz0,
-		Fx_rot90, Fx_cmixa, Fx_Desat,
+		Fx_rot90, Fx_cmixa, Fx_desat, Fx_ctr2x2,
 		Fx_xper };
 
 Fx fx_list[] = {
@@ -34,7 +34,8 @@ Fx fx_list[] = {
 	{ "rot90",		Fx_rot90,	0,	0 },
 	{ "cmixa",		Fx_cmixa,	0,	1 },
 	{ "xper",		Fx_xper,	0,	1 },
-	{ "desat",		Fx_Desat,	0,	1 },
+	{ "desat",		Fx_desat,	0,	1 },
+	{ "ctr2x2",		Fx_ctr2x2,	0,	1 },
 	{ NULL,			0,	0 }
 	};
 
@@ -170,11 +171,15 @@ switch (action) {
 		fprintf(stderr, "halfsize was not implemented\n");
 		return -3;
 
-	case Fx_Desat:
+	case Fx_desat:
 		fimg_copy_data(&src, &dest);
 		foo = fimg_mix_rgb_gray(&dest, global_fvalue);
 		break;
 
+	case Fx_ctr2x2:
+		foo = fimg_contour_2x2(&src, &dest, 0);
+		break;
+
 	default:
 		fprintf(stderr, "%s %s : %d is bad action\n",
 					__FILE__, __func__, action);