holy cognitohazard batman

bin/dither.c

@@ -0,0 +1,116 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include <cammy/image.h>
+#include <cammy/photo.h>
+
+#include "commands.h"
+
+static cammy_image_color palette[4] = {
+    {   0,   0,   0, 255 },
+    {  85,  85,  85, 255 },
+    { 171, 171, 171, 255 },
+    { 255, 255, 255, 255 }
+};
+
+static void usage(int argc, char **argv, const char *message, ...) {
+    if (message) {
+        va_list args;
+
+        va_start(args, message);
+        vfprintf(stderr, message, args);
+        va_end(args);
+         fprintf(stderr, "\n");
+    }
+
+    fprintf(stderr, "usage: %1$s convert input.png output.png\n", argv[0]);
+
+    exit(1);
+}
+
+static cammy_image *image_dither(cammy_image *image) {
+    cammy_image *image_tile,
+                *dest;
+
+    cammy_image_region from = {
+        0, 0, image->width, image->height
+    };
+
+    cammy_image_point to = {
+        0, 0
+    };
+
+    if ((image_tile = cammy_image_new(CAMMY_IMAGE_TILE,
+                                      CAMMY_IMAGE_2BPP,
+                                      palette,
+                                      image->width,
+                                      image->height)) == NULL) {
+        goto error_image_new_2bpp;
+    }
+
+    cammy_image_copy(image_tile, image, &to, &from);
+
+    if ((dest = cammy_image_new(CAMMY_IMAGE_BITMAP,
+                                CAMMY_IMAGE_24BPP_RGB,
+                                palette,
+                                image->width,
+                                image->height)) == NULL) {
+        goto error_image_new_dest;
+    }
+
+    cammy_image_copy(dest, image_tile, &to, &from);
+
+    cammy_image_destroy(image_tile);
+
+    return dest;
+
+error_image_new_dest:
+    cammy_image_destroy(image_tile);
+
+error_image_new_2bpp:
+    return NULL;
+}
+
+int cammy_dither(int argc, char **argv) {
+    cammy_image *image_in,
+                *image_out;
+
+    if (argc < 3) {
+        usage(argc, argv, "No PNG input file provided");
+    } else if (argc < 4) {
+        usage(argc, argv, "No PNG output filename provided");
+    }
+
+    if ((image_in = cammy_image_open(argv[2])) == NULL) {
+        goto error_image_open;
+    }
+
+    if ((image_out = image_dither(image_in)) == NULL) {
+        goto error_image_dither;
+    }
+
+    if (cammy_image_save(image_out, argv[3]) < 0) {
+        goto error_image_save;
+    }
+
+    cammy_image_destroy(image_out);
+    cammy_image_destroy(image_in);
+
+    return 0;
+
+error_image_save:
+    cammy_image_destroy(image_out);
+
+error_image_dither:
+    cammy_image_destroy(image_in);
+
+error_image_open:
+    return 1;
+}