diff --git a/.gitignore b/.gitignore
index a7aefbd..7a5b7cb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -55,6 +55,7 @@ tools/fimg2tiff
 tools/fimg2fits
 tools/fimg2text
 tools/fimgstats
+tools/fimghalfsize
 tools/mkfimg
 tools/png2fimg
 tools/addtga2fimg
diff --git a/tools/Makefile b/tools/Makefile
index b087067..53b2985 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -10,7 +10,8 @@ DEPS = ../floatimg.h  ../libfloatimg.a Makefile
 
 all:	fimg2pnm mkfimg png2fimg fimgstats fimg2png		\
 	fimg2tiff fimg2text fimg2fits				\
-	addpnm2fimg cumulfimgs fimgops fimgfx
+	addpnm2fimg cumulfimgs fimgops fimgfx			\
+	fimghalfsize
 
 fimgstats:	fimgstats.c $(DEPS)
 	gcc $(COPT) $< ../libfloatimg.a -o $@ 
@@ -27,6 +28,9 @@ fimgops:		fimgops.c  $(DEPS)
 fimgfx:		fimgfx.c  $(DEPS)
 	gcc $(COPT) $< ../libfloatimg.a -o $@ 
 
+fimghalfsize:		fimghalfsize.c  $(DEPS)
+	gcc $(COPT) $< ../libfloatimg.a -o $@ 
+
 fimg2pnm:	fimg2pnm.c  $(DEPS)
 	gcc $(COPT) $< ../libfloatimg.a -o $@ 
 
diff --git a/tools/fimghalfsize.c b/tools/fimghalfsize.c
new file mode 100644
index 0000000..b522778
--- /dev/null
+++ b/tools/fimghalfsize.c
@@ -0,0 +1,77 @@
+/*
+*/
+
+#include  <stdio.h>
+#include  <unistd.h>			/* pour getopt */
+#include  <stdlib.h>
+
+#include  "../floatimg.h"
+
+int		verbosity;
+
+/* ------------------------------------------------------------- */
+int faire_un_halfsize(char *iname, char *oname, int notused)
+{
+FloatImg	src, dst;
+int		foo;
+
+foo = fimg_create_from_dump(iname, &src);
+if (foo) {
+	fprintf(stderr, "create fimg from '%s' -> %d\n", iname, foo);
+	return -1;
+	}
+
+memset(&dst, 0, sizeof(FloatImg));
+foo = fimg_halfsize_0(&src, &dst, 0);
+if (foo) {
+	fprintf(stderr, "halfize fail -> %d\n", foo);
+	return -1;
+	}
+
+foo = fimg_dump_to_file(&dst, oname, 0);
+if (foo) {
+	fprintf(stderr, "save to '%s' -> %d\n", oname, foo);
+	return -1;
+	}
+
+return -1;
+}
+
+/* ------------------------------------------------------------- */
+void help(int u)
+{
+
+}
+/* ------------------------------------------------------------- */
+
+int main(int argc, char *argv[])
+{
+int		foo, opt, action;
+
+char		*srcname = "";
+char		*dstname = "out.fimg";
+
+while ((opt = getopt(argc, argv, "hv")) != -1) {
+	switch(opt) {
+		case 'h':	help(0);			break;
+		case 'v':	verbosity++;			break;
+		}
+	}
+
+if (2 != argc-optind) {
+	fprintf(stderr, "error: %s need two filenames\n", argv[0]);
+	exit(1);
+	}
+
+srcname = argv[optind];
+dstname = argv[optind+1];
+
+fprintf(stderr, "%s:  optind: %d  src: %s  dst: %s\n", argv[0], optind,
+				 srcname, dstname);
+
+foo = faire_un_halfsize(srcname, dstname, 0);
+
+
+return 0;
+}
+/* ------------------------------------------------------------- */