diff --git a/funcs/histogram.c b/funcs/histogram.c
index 158e3920..322e3f0f 100644
--- a/funcs/histogram.c
+++ b/funcs/histogram.c
@@ -18,7 +18,9 @@ float		maxval;
 int		x, y, idx;
 float		rgb[3], moy;
 
+#if DEBUG_LEVEL
 fprintf(stderr, ">>> %s ( %p %p %d )\n", __func__, src, ghist, sz);
+#endif
 
 maxval = fimg_get_maxvalue(src);
 
@@ -46,7 +48,7 @@ return -66;
 }
 /* --------------------------------------------------------------------- */
 
-#define NSLICES 999
+#define NSLICES 1000
 
 int fimg_essai_histo(FloatImg *src, char *outpic, int k)
 {
@@ -60,14 +62,20 @@ memset(histo, 0, NSLICES*sizeof(long));
 
 foo = fimg_calcul_histo(src, histo, NSLICES);
 
-for (foo=0; foo<NSLICES; foo++)	{
-	printf("%7d   %ld\n", foo, histo[foo]);
-	}
+// for (foo=0; foo<NSLICES; foo++)	{
+//	printf("%7d   %ld\n", foo, histo[foo]);
+//	}
 
 pipe = popen("gnuplot", "w");
-fprintf(pipe, "set term png    size 1000,400\n");
-fprintf(pipe, "set output \"histo.png\"\n");
-fprintf(pipe, "plot 'toto' with lines\n");
+fprintf(pipe, "set term png    size 1024,512\n");
+fprintf(pipe, "set grid\n");
+fprintf(pipe, "set output \"%s\"\n", outpic);
+fprintf(pipe, "plot '/dev/stdin' with lines\n");
+
+for (foo=0; foo<NSLICES; foo++)	{
+	fprintf(pipe, "%d %ld\n", foo, histo[foo]);
+	}
+
 fclose(pipe);
 
 
diff --git a/funcs/t.c b/funcs/t.c
index 668d242e..83ac193c 100644
--- a/funcs/t.c
+++ b/funcs/t.c
@@ -405,7 +405,6 @@ return 0;
 		/* func in histogram.c */
 int fimg_essai_histo(FloatImg *src, char *outpic, int k);
 
-
 int essai_histogramme(char *fname, int k)
 {
 FloatImg	fimg;