diff --git a/fb2png/img_process.c b/fb2png/img_process.c
new file mode 100644
index 0000000..eb75e9a
--- /dev/null
+++ b/fb2png/img_process.c
@@ -0,0 +1,254 @@
+/*
+ *   -- http://android-fb2png.googlecode.com/svn/trunk/img_process.c --
+ *
+ *   Copyright 2011, Kyan He <kyan.ql.he@gmail.com>
+ *
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <png.h>
+
+#include "img_process.h"
+#include "log.h"
+
+int rgb565_to_rgb888(const char* src, char* dst, size_t pixel)
+{
+    struct rgb565  *from;
+    struct rgb888  *to;
+
+    from = (struct rgb565 *) src;
+    to = (struct rgb888 *) dst;
+
+    int i = 0;
+    /* traverse pixel of the row */
+    while(i++ < pixel) {
+
+        to->r = from->r;
+        to->g = from->g;
+        to->b = from->b;
+        /* scale */
+        to->r <<= 3;
+        to->g <<= 2;
+        to->b <<= 3;
+
+        to++;
+        from++;
+    }
+
+    return 0;
+}
+
+int argb8888_to_rgb888(const char* src, char* dst, size_t pixel)
+{
+    int i;
+    struct argb8888  *from;
+    struct rgb888  *to;
+
+    from = (struct argb8888 *) src;
+    to = (struct rgb888 *) dst;
+
+    i = 0;
+    /* traverse pixel of the row */
+    while(i++ < pixel) {
+
+        to->r = from->r;
+        to->g = from->g;
+        to->b = from->b;
+
+        to++;
+        from++;
+    }
+
+    return 0;
+}
+
+int abgr8888_to_rgb888(const char* src, char* dst, size_t pixel)
+{
+    int i;
+    struct abgr8888  *from;
+    struct rgb888  *to;
+
+    from = (struct abgr8888 *) src;
+    to = (struct rgb888 *) dst;
+
+    i = 0;
+    /* traverse pixel of the row */
+    while(i++ < pixel) {
+
+        to->r = from->r;
+        to->g = from->g;
+        to->b = from->b;
+
+        to++;
+        from++;
+    }
+
+    return 0;
+}
+
+int bgra8888_to_rgb888(const char* src, char* dst, size_t pixel)
+{
+    int i;
+    struct bgra8888  *from;
+    struct rgb888  *to;
+
+    from = (struct bgra8888 *) src;
+    to = (struct rgb888 *) dst;
+
+    i = 0;
+    /* traverse pixel of the row */
+    while(i++ < pixel) {
+
+        to->r = from->r;
+        to->g = from->g;
+        to->b = from->b;
+
+        to++;
+        from++;
+    }
+
+    return 0;
+}
+
+int rgba8888_to_rgb888(const char* src, char* dst, size_t pixel)
+{
+    int i;
+    struct rgba8888  *from;
+    struct rgb888  *to;
+
+    from = (struct rgba8888 *) src;
+    to = (struct rgb888 *) dst;
+
+    i = 0;
+    /* traverse pixel of the row */
+    while(i++ < pixel) {
+
+        to->r = from->r;
+        to->g = from->g;
+        to->b = from->b;
+
+        to++;
+        from++;
+    }
+
+    return 0;
+}
+
+static void
+stdio_write_func (png_structp png, png_bytep data, png_size_t size)
+{
+    FILE *fp;
+    size_t ret;
+
+    fp = png_get_io_ptr (png);
+    while (size) {
+        ret = fwrite (data, 1, size, fp);
+        size -= ret;
+        data += ret;
+      if (size && ferror (fp))
+         E("write: %m\n");
+   }
+}
+
+static void
+png_simple_output_flush_fn (png_structp png_ptr)
+{
+}
+
+static void
+png_simple_error_callback (png_structp png,
+                       png_const_charp error_msg)
+{
+    E("png error: %s\n", error_msg);
+}
+
+static void
+png_simple_warning_callback (png_structp png,
+                         png_const_charp error_msg)
+{
+    fprintf(stderr, "png warning: %s\n", error_msg);
+}
+
+/* save rgb888 to png format in fp */
+int save_png(const char* path, const char* data, int width, int height)
+{
+    FILE *fp;
+    png_byte **volatile rows;
+    png_struct *png;
+    png_info *info;
+
+    fp = fopen(path, "w");
+    if (!fp) {
+        int errsv = errno;
+        E("Cannot open file %s for writing.\n", path);
+        return errsv;
+    }
+
+    rows = malloc(height * sizeof rows[0]);
+    if (!rows) goto oops;
+
+    int i;
+    for (i = 0; i < height; i++)
+        rows[i] = (png_byte *) data + i * width * 3 /*fb.stride*/;
+
+    png = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL,
+                               png_simple_error_callback,
+                               png_simple_warning_callback);
+    if (!png) {
+        E("png_create_write_struct failed\n");
+        goto oops;
+    }
+
+    info = png_create_info_struct (png);
+    if (!info) {
+        E("png_create_info_struct failed\n");
+        png_destroy_write_struct (&png, NULL);
+        goto oops;
+    }
+
+    png_set_write_fn (png, fp, stdio_write_func, png_simple_output_flush_fn);
+    png_set_IHDR (png, info,
+            width,
+            height,
+#define DEPTH 8
+            DEPTH,
+        PNG_COLOR_TYPE_RGB,
+        PNG_INTERLACE_NONE,
+        PNG_COMPRESSION_TYPE_DEFAULT,
+        PNG_FILTER_TYPE_DEFAULT);
+
+    png_color_16 white;
+
+    white.gray = (1 << DEPTH) - 1;
+    white.red = white.blue = white.green = white.gray;
+
+    png_set_bKGD (png, info, &white);
+    png_write_info (png, info);
+
+    png_write_image (png, rows);
+    png_write_end (png, info);
+
+    png_destroy_write_struct (&png, &info);
+
+    fclose(fp);
+    free (rows);
+    return 0;
+
+oops:
+    fclose(fp);
+    free (rows);
+    return -1;
+}