* sharpen.c: add a sharpen filter example, using our generic convolution

routine. Note that it is not the "real" sharpen which should be built
    on top of a gaussian kernel.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@2662 92316355-f0b4-4df1-b90c-862c8a59935f

.gitignore

@@ -14,6 +14,7 @@ examples/blur
 examples/dither
 examples/edd
 examples/img2rubik
+examples/sharpen
 test/u8tof32tou8
 stamp-h1
 .auto

examples/Makefile.am

@@ -2,7 +2,7 @@
 
 AM_CPPFLAGS = -I$(top_srcdir) -I$(top_srcdir)/pipi
 
-bin_PROGRAMS = blur dither edd img2rubik
+bin_PROGRAMS = blur dither edd img2rubik sharpen
 
 blur_SOURCES = blur.c
 blur_LDADD = ../pipi/libpipi.la
@@ -16,3 +16,6 @@ edd_LDADD = ../pipi/libpipi.la
 img2rubik_SOURCES = img2rubik.c
 img2rubik_LDADD = ../pipi/libpipi.la
 
+sharpen_SOURCES = sharpen.c
+sharpen_LDADD = ../pipi/libpipi.la
+

examples/sharpen.c

@@ -0,0 +1,43 @@
+#include "config.h"
+#include "common.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <pipi.h>
+
+double kern[] =
+{
+       0., -.0625, -.125, -.0625,     0.,
+   -.0625,  -.125,  -.25,  -.125, -.0625,
+    -.125,   -.25,   3.5,   -.25,  -.125,
+   -.0625,  -.125,  -.25,  -.125, -.0625,
+       0., -.0625, -.125, -.0625,     0.,
+};
+
+int main(int argc, char *argv[])
+{
+    char *srcname = NULL, *dstname = NULL;
+    pipi_image_t *img, *newimg;
+
+    if(argc < 3)
+    {
+        fprintf(stderr, "%s: too few arguments\n", argv[0]);
+        fprintf(stderr, "Usage: %s <src> <dest>\n", argv[0]);
+        return EXIT_FAILURE;
+    }
+
+    srcname = argv[1];
+    dstname = argv[2];
+
+    img = pipi_load(srcname);
+    newimg = pipi_convolution(img, 5, 5, kern);
+    pipi_free(img);
+
+    pipi_save(newimg, dstname);
+    pipi_free(newimg);
+
+    return 0;
+}
+