diff --git a/.gitignore b/.gitignore
index 78d14113..6a7df6e0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,7 +5,6 @@ lib/*.fimg
 lib/*.png
 lib/*.gif
 
-funcs/*.o
 
 *.a
 gmon.out
@@ -26,7 +25,9 @@ doc/*.ilg
 doc/*.ind
 
 funcs/t
+funcs/*.o
 funcs/*.png
+funcs/*.gif
 
 scripts/*.fimg
 scripts/*.pnm
diff --git a/floatimg.h b/floatimg.h
index 1967db0a..3889d096 100644
--- a/floatimg.h
+++ b/floatimg.h
@@ -78,6 +78,7 @@ int fimg_maximum(FloatImg *a, FloatImg *b, FloatImg *d);
 
 /*	'sfx0' module 			*/
 int fimg_killcolors_a(FloatImg *fimg, float fval);
+int fimg_killcolors_b(FloatImg *fimg, float fval);
 
 
 /*	PNM files module		*/
diff --git a/funcs/sfx0.c b/funcs/sfx0.c
index d602691e..9f9c59d2 100644
--- a/funcs/sfx0.c
+++ b/funcs/sfx0.c
@@ -22,15 +22,33 @@ if (FIMG_TYPE_RGB != fimg->type) {
 	}
 
 nbpix = fimg->width * fimg->height;
-
 for (foo=0; foo<nbpix; foo++) {
-
 	if (fimg->R[foo] > fimg->G[foo])
 		fimg->B[foo] = fimg->R[foo];
 	else
 		fimg->B[foo] = fimg->G[foo];
-	
-	}
+		}
+
+return 0;
+}
+/* --------------------------------------------------------------------- */
+int fimg_killcolors_b(FloatImg *fimg, float fval)
+{
+int		nbpix, foo;
+
+if (FIMG_TYPE_RGB != fimg->type) {
+	fprintf(stderr, "%s: bad src type %d on %p\n", __func__,
+					fimg->type, fimg);
+	return -8;
+	}
+
+nbpix = fimg->width * fimg->height;
+for (foo=0; foo<nbpix; foo++) {
+	if (fimg->R[foo] > fimg->B[foo])
+		fimg->G[foo] = fimg->R[foo];
+	else
+		fimg->G[foo] = fimg->B[foo];
+		}
 
 return 0;
 }
diff --git a/funcs/t.c b/funcs/t.c
index b6eff52b..54e6cffb 100644
--- a/funcs/t.c
+++ b/funcs/t.c
@@ -18,14 +18,23 @@ int essai_sfx0(char *infile)
 FloatImg	fimg;
 int		foo;
 
-fimg_create(&fimg, 512, 512, FIMG_TYPE_RGB);
+if (NULL != infile) {
+	fprintf(stderr, "loading %s\n", infile);
+	fimg_create_from_dump(infile, &fimg);
+	}
+else	{
+	fimg_create(&fimg, 512, 512, FIMG_TYPE_RGB);
+	fimg_draw_something(&fimg);
+	}
 
-fimg_draw_something(&fimg);
 foo = fimg_save_as_pnm(&fimg, "something.pnm", 0);
 
 foo = fimg_killcolors_a(&fimg, 0.0);
+foo = fimg_save_as_pnm(&fimg, "colorskilled-a.pnm", 0);
+
+foo = fimg_killcolors_b(&fimg, 0.0);
+foo = fimg_save_as_pnm(&fimg, "colorskilled-b.pnm", 0);
 
-foo = fimg_save_as_pnm(&fimg, "colorskilled.pnm", 0);
 
 return 0;
 }
@@ -125,7 +134,7 @@ int		foo;
 
 puts("++++++++++++++++++++++++++++++++");
 
-foo = essai_sfx0(NULL);
+foo = essai_sfx0("03384.fimg");
 
 return 0;
 }