diff --git a/funcs/decomprgb.c b/funcs/decomprgb.c
index 58ef5343..55f938e8 100644
--- a/funcs/decomprgb.c
+++ b/funcs/decomprgb.c
@@ -60,6 +60,7 @@ for (y=0; y<h2; y++)
 			getRpix(psrc, x2+1, y2+1);
 		cumul /= 4, vgray = cumul;
 		pdst->R[pixidx(pdst,x,y)] = cumul;
+		pdst->R[pixidx(pdst,x+w2,y+h2)] = cumul;
 
 		cumul = getGpix(psrc, x2, y2) +
 			getGpix(psrc, x2, y2+1) +
@@ -67,6 +68,7 @@ for (y=0; y<h2; y++)
 			getGpix(psrc, x2+1, y2+1);
 		cumul /= 4, vgray += cumul;
 		pdst->G[pixidx(pdst,x+w2,y)] = cumul;
+		pdst->G[pixidx(pdst,x+w2,y+h2)] = cumul;
 
 		cumul = getBpix(psrc, x2, y2) +
 			getBpix(psrc, x2, y2+1) +
@@ -74,10 +76,8 @@ for (y=0; y<h2; y++)
 			getBpix(psrc, x2+1, y2+1);
 		cumul /= 4, vgray += cumul;
 		pdst->B[pixidx(pdst,x,y+h2)] = cumul;
+		pdst->B[pixidx(pdst,x+w2,y+h2)] = cumul;
 
-		idx = pixidx(pdst,x+w2,y+h2);
-		pdst->R[idx] = pdst->G[idx] = 		\
-				pdst->B[idx] =  vgray / 3.0;
 		}
 
 	}
diff --git a/funcs/t.c b/funcs/t.c
index ad767f0c..3734eb7e 100644
--- a/funcs/t.c
+++ b/funcs/t.c
@@ -232,7 +232,7 @@ switch(opt) {
 		foo = essai_split_level(filename, outfile, 0);
 		break;
 	case DecompRgbz:
-		foo = essai_decomprgb(filename, outfile);
+		foo = essai_decomprgb_color(filename, outfile);
 		break;
 	case Rectangle:
 		essai_rectangle(outfile, 0);
diff --git a/funcs/tests.c b/funcs/tests.c
index 6ff3e503..ec0ee738 100644
--- a/funcs/tests.c
+++ b/funcs/tests.c
@@ -75,7 +75,7 @@ return 0;
 }
 /* --------------------------------------------------------------------- */
 /* --------------------------------------------------------------------- */
-int essai_decomprgb(char *inf, char *outf)
+int essai_decomprgb_color(char *inf, char *outf)
 {
 int		foo;
 FloatImg	src, dst;
@@ -90,7 +90,7 @@ if (0 != foo) {
 	}
 fimg_clone(&src, &dst, 1);
 
-foo = fimg_decomp_rgbz_gray(&src, &dst, 0);
+foo = fimg_decomp_rgbz_color(&src, &dst, 0);
 if (foo) {
 	fprintf(stderr, "%s:%s(): fail %d line %d\n",
 			__FILE__, __func__, foo, __LINE__);
diff --git a/funcs/tests.h b/funcs/tests.h
index ef196d07..a4c5a090 100644
--- a/funcs/tests.h
+++ b/funcs/tests.h
@@ -6,7 +6,7 @@
 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(char *inf, char *outf);
+int essai_decomprgb_color(char *inf, char *outf);
 int essai_split_level(char *inf, char *outf, int flags);
 
 int essai_displacement(char *infile, char *outfile);
@@ -35,3 +35,4 @@ int essai_openexr(char *inf, char *outf, int flags);
 
 int essai_pixelize(char *infile, char *outfile);
 
+int essai_rectangle(char *outf, int k);