diff --git a/floatimg.h b/floatimg.h
index 797dbd8..214d828 100644
--- a/floatimg.h
+++ b/floatimg.h
@@ -20,7 +20,7 @@
  *	https://git.tetalab.org/tTh/FloatImg
  */
 
-#define		FIMG_VERSION	(223)
+#define		FIMG_VERSION	(224)
 #define		RELEASE_NAME	("noname")
 
 /* XXX add a test for stdint.h / uint32_t XXX */
@@ -153,6 +153,7 @@ typedef struct {
  */
 int fimg_killborders(FloatImg *img);
 int fimg_lissage_2x2(FloatImg *img);
+int fimg_lissage_3x3(FloatImg *img);
 int fimg_show_filter(char *title, FimgFilter3x3 *filtr);
 int fimg_filter_3x3(FloatImg *s, FloatImg *d, FimgFilter3x3 *filtr);
 
diff --git a/funcs/filtrage.c b/funcs/filtrage.c
index e4b25b2..212a870 100644
--- a/funcs/filtrage.c
+++ b/funcs/filtrage.c
@@ -200,7 +200,6 @@ for (idx=0; idx<h; idx++) {
 	}
 
 o = w * (h - 1);
-
 for (idx=0; idx<w; idx++) {
 #if FAST
 	img->R[idx] = 0.0;
@@ -233,4 +232,42 @@ fimg_killborders(img);
 return foo;
 }
 /* -------------------------------------------------------------------- */
+/* -------------------------------------------------------------------- */
+int fimg_lissage_3x3(FloatImg *img)
+{
+int		foo;
+FloatImg	tmp;
+
+fprintf(stderr, ">>> %s ( %p )\n", __func__, img);
+
+static FimgFilter3x3   lowpass = {
+                {
+                1.0,    2.0,    1.0,
+                2.0,    4.0,    2.0,
+                1.0,    2.0,    1.0,
+                },
+        16.0,   0.0
+        };
+
+foo = fimg_clone(img, &tmp, 1);
+if (foo) {
+	fprintf(stderr, "%s: clone -> %d\n", __func__, foo);
+	abort();
+	}
+foo = fimg_filter_3x3(&tmp, img, &lowpass);
+if (foo) {
+	fprintf(stderr, "%s: lowpass -> %d\n", __func__, foo);
+	abort();
+	}
+foo = fimg_destroy(&tmp);
+if (foo) {
+	fprintf(stderr, "%s: destroy -> %d\n", __func__, foo);
+	abort();
+	}
+
+fimg_killborders(img);
+
+return 0;
+}
+/* -------------------------------------------------------------------- */