diff --git a/floatimg.h b/floatimg.h
index 623a4b29..f86e984a 100644
--- a/floatimg.h
+++ b/floatimg.h
@@ -4,7 +4,7 @@
  *	http://la.buvette.org/photos/cumul
  */
 
-#define		FIMG_VERSION	124
+#define		FIMG_VERSION	125
 
 /*
  *	in memory descriptor
@@ -102,11 +102,16 @@ int fimg_filter_3x3(FloatImg *s, FloatImg *d, FimgFilter3x3 *filtr);
 
 int fimg_contour_2x2(FloatImg *psrc, FloatImg *pdst, int reverse);
 
-/*	'sfx0' module 			*/
+/*	 module sfx0.c			*/
 int fimg_killcolors_a(FloatImg *fimg, float fval);
 int fimg_killcolors_b(FloatImg *fimg, float fval);
 int fimg_colors_mixer_a(FloatImg *fimg, float fval);
 
+/*	 module sfx1.c			*/
+int fimg_highlight_color(FloatImg *src, FloatImg *dst,
+					char color, float fval);
+
+
 /*	funcs/rotate.c module		*/
 /*	#coronamaison			*/
 int fimg_rotate_90(FloatImg *src, FloatImg *dst, int notused);
diff --git a/funcs/Makefile b/funcs/Makefile
index ee4c6493..c43a5f0d 100644
--- a/funcs/Makefile
+++ b/funcs/Makefile
@@ -4,7 +4,8 @@ COPT = -Wall -fpic -g -no-pie -DDEBUG_LEVEL=0
 DEPS = ../floatimg.h Makefile
 
 OBJS = fimg-png.o fimg-tiff.o misc-plots.o filtrage.o utils.o	\
-	fimg-libpnm.o rampes.o sfx0.o geometry.o rotate.o	\
+	fimg-libpnm.o rampes.o sfx0.o sfx1.o			\
+	geometry.o rotate.o					\
 	equalize.o fimg-fits.o saturation.o histogram.o		\
 	hsv.o classif.o contour2x2.o qsortrgb.o exporter.o	\
 	displacement.o dithering.o plasmas.o
@@ -77,6 +78,9 @@ plasmas.o:		plasmas.c $(DEPS)
 sfx0.o:			sfx0.c $(DEPS)
 	gcc $(COPT) -c $<
 
+sfx1.o:			sfx1.c $(DEPS)
+	gcc $(COPT) -c $<
+
 contour2x2.o:		contour2x2.c $(DEPS)
 	gcc $(COPT) -c $<
 
diff --git a/funcs/sfx1.c b/funcs/sfx1.c
new file mode 100644
index 00000000..58fc2acf
--- /dev/null
+++ b/funcs/sfx1.c
@@ -0,0 +1,107 @@
+/*
+ *		FLOATIMG - a kluge from tTh
+ *	effets spéciaux bizarres sur les couleurs.
+ *	nouveau pour un truc chelou avec Maëva
+ */
+
+#include  <stdio.h>
+#include  <string.h>
+
+#include  "../floatimg.h"
+
+/*			WARNING
+		some crapy code cuted & pasted here			*/
+
+/* --------------------------------------------------------------------- */
+static void highlight_red(FloatImg *src, FloatImg *dst, float fval)
+{
+int		sz, idx;
+
+sz = src->width * src->height;
+for (idx=0; idx<sz; idx++) {
+	dst->G[idx] = src->G[idx];
+	dst->B[idx] = src->B[idx];
+	if ( 	(src->G[idx] < src->R[idx])	&&
+		(src->B[idx] < src->R[idx])	) {
+		dst->R[idx] = src->R[idx] * fval;
+		}
+	else	{
+		dst->R[idx] = src->R[idx];
+		}
+	}
+}
+/* --------------------------------------------------------------------- */
+static void highlight_green(FloatImg *src, FloatImg *dst, float fval)
+{
+int		sz, idx;
+
+sz = src->width * src->height;
+for (idx=0; idx<sz; idx++) {
+	dst->R[idx] = src->R[idx];
+	dst->B[idx] = src->B[idx];
+	if ( 	(src->R[idx] < src->R[idx])	&&
+		(src->B[idx] < src->R[idx])	) {
+		dst->G[idx] = src->G[idx] * fval;
+		}
+	else	{
+		dst->G[idx] = src->G[idx];
+		}
+	}
+}
+/* --------------------------------------------------------------------- */
+static void highlight_blue(FloatImg *src, FloatImg *dst, float fval)
+{
+int		sz, idx;
+
+sz = src->width * src->height;
+for (idx=0; idx<sz; idx++) {
+	dst->G[idx] = src->G[idx];
+	dst->R[idx] = src->R[idx];
+	if ( 	(src->G[idx] < src->B[idx])	&&
+		(src->R[idx] < src->B[idx])	) {
+		dst->B[idx] = src->B[idx] * fval;
+		}
+	else	{
+		dst->B[idx] = src->B[idx];
+		}
+	}
+}
+/* --------------------------------------------------------------------- */
+int fimg_highlight_color(FloatImg *src, FloatImg *dst, char color, float fval)
+{
+int		sz;
+
+#ifdef DEBUG_LEVEL
+fprintf(stderr, ">>> %s ( %p %p [%c] %f )\n", __func__,
+			src, dst, color, fval);
+#endif
+
+if (FIMG_TYPE_RGB != src->type) {
+	fprintf(stderr, "%s: bad src type %d on %p\n", __func__,
+					src->type, src);
+	return -8;
+	}
+if (fimg_images_not_compatible(src, dst)) {
+	fprintf(stderr, "oh fuck in %s\n", __func__);
+	return -9;
+	}
+
+switch (color) {
+
+	case 'r': case 'R':
+		highlight_red(src, dst, fval);			break;
+	case 'g': case 'G':
+		highlight_green(src, dst, fval);		break;
+	case 'b': case 'B':
+		highlight_blue(src, dst, fval);			break;
+
+	default:
+		fprintf(stderr, "%s: '%c' is invalid\n", __func__, color);
+		return -11;
+		break;			/* nottreached */
+	}
+
+return 0;
+}
+/* --------------------------------------------------------------------- */
+/* --------------------------------------------------------------------- */
diff --git a/funcs/t.c b/funcs/t.c
index 0d448270..671cc418 100644
--- a/funcs/t.c
+++ b/funcs/t.c
@@ -21,7 +21,7 @@ float		global_fvalue;
 /* --------------------------------------------------------------------- */
 enum nCmd { Equalize=1, Rotate, Sfx0, F3x3, MIRE, Wfits, Wpng, Wtiff,
 			Histo, Hsv, Classif, Ctr2x2, Qsortrgb,
-			Displace, ReadPNG, Plasmas  };
+			Displace, ReadPNG, Plasmas, Hilight  };
 typedef struct {
 	char	*name;
 	int	Cmd;
@@ -44,6 +44,7 @@ Command commands[] = {
 	{ "displace",	Displace	},
 	{ "readpng",	ReadPNG		},
 	{ "plasma",	Plasmas		},
+	{ "hilight",	Hilight		},
 	{ NULL,		0		}
 	} ;
 
@@ -194,6 +195,9 @@ switch(opt) {
 		fprintf(stderr, "rotate not implemented (%d)\n", rand());
 		foo = 0;
 		break;
+	case Hilight:
+		foo = essai_highlights(filename, outfile, 0, global_fvalue);
+		break;
 	default:
 		fprintf(stderr, "'%s' is a bad command\n", command);
 		exit(1);
diff --git a/funcs/tests.c b/funcs/tests.c
index 43a364ca..b79c08a4 100644
--- a/funcs/tests.c
+++ b/funcs/tests.c
@@ -16,6 +16,39 @@
 
 extern int		verbosity;
 
+/* --------------------------------------------------------------------- */
+/* nouveau 20 mars 2021 - rue d'Aragon */
+int essai_highlights(char *inf, char *outf, int ikoef, float fkoef)
+{
+FloatImg	src, dst;
+int		foo;
+
+fprintf(stderr, ">>> %s ( '%s' '%s' %d %g )\n", __func__,
+				inf, outf, ikoef, fkoef);
+
+foo = fimg_create_from_dump(inf, &src);
+if (0 != foo) {
+	fprintf(stderr, "%s: err %d loading image '%s'\n", __func__,
+				foo, 		inf);
+	return foo;
+	}
+
+fimg_clone(&src, &dst, 0);
+
+foo = fimg_highlight_color(&src, &dst, 'R', fkoef);
+if (foo) {
+	fprintf(stderr, "%s: err %d ?\n", __func__, foo);
+	return foo;
+	}
+
+foo = fimg_export_picture(&dst, outf, 0);
+if (foo) {
+	fprintf(stderr, "%s : err %d saving result\n", __func__, foo);
+	return foo;
+	}
+
+return 0;
+}
 /* --------------------------------------------------------------------- */
 
 int essai_plasma(char *infile, char *outfile, int ikoef, float fkoef)
diff --git a/funcs/tests.h b/funcs/tests.h
index 58450d17..419aec1c 100644
--- a/funcs/tests.h
+++ b/funcs/tests.h
@@ -25,4 +25,5 @@ int essai_histogramme(char *fname, int k);
 
 int essai_lecture_png(char *fname, char *outfile, int notused);
 
+int essai_highlights(char *inf, char *outf, int ikoef, float fkoef);