[maemo-commits] [maemo-commits] r18648 - in projects/haf/trunk/hildon-theme-tools: . src

[From: subversion at stage.maemo.org]

Author: danielb
Date: 2009-06-08 14:09:08 +0300 (Mon, 08 Jun 2009)
New Revision: 18648

Modified:
   projects/haf/trunk/hildon-theme-tools/ChangeLog
   projects/haf/trunk/hildon-theme-tools/src/common.c
   projects/haf/trunk/hildon-theme-tools/src/dither.c
Log:
2009-06-08  Daniel Borgmann  <danielb at openismus.com>

	* src/common.c (dither_pixbuf): New dither algorithm.
	* src/dither.c (main): Fix a crasher.




Modified: projects/haf/trunk/hildon-theme-tools/ChangeLog
===================================================================
--- projects/haf/trunk/hildon-theme-tools/ChangeLog	2009-06-08 10:01:09 UTC (rev 18647)
+++ projects/haf/trunk/hildon-theme-tools/ChangeLog	2009-06-08 11:09:08 UTC (rev 18648)
@@ -1,3 +1,8 @@
+2009-06-08  Daniel Borgmann  <danielb at openismus.com>
+
+	* src/common.c (dither_pixbuf): New dither algorithm.
+	* src/dither.c (main): Fix a crasher.
+
 2009-05-29  Daniel Borgmann  <danielb at openismus.com>
 
 	[0.6.1-1 release]

Modified: projects/haf/trunk/hildon-theme-tools/src/common.c
===================================================================
--- projects/haf/trunk/hildon-theme-tools/src/common.c	2009-06-08 10:01:09 UTC (rev 18647)
+++ projects/haf/trunk/hildon-theme-tools/src/common.c	2009-06-08 11:09:08 UTC (rev 18648)
@@ -254,55 +254,35 @@
 /* Dither a pixmap to 5658 RGBA mode. */
 void                            dither_pixbuf (GdkPixbuf *pixbuf)
 {
-  gint    x, y;
-  guchar *gpixels;
-  guchar *pixit;
-  gint width, height;
-  gint rowstride;
+  /* http://en.wikipedia.org/wiki/Floyd-Steinberg_dithering */
+  guchar          *pixels;
+  gint             width, height;
+  gint             x, y;
+  gint             bpp;
+  gint             rowstride;
   
-  if (gdk_pixbuf_get_bits_per_sample (pixbuf) != 8)
-    {
-      printf("Dithering failed: Can only use 8bpp\n");
-      return;
-    }
-
-  gpixels = gdk_pixbuf_get_pixels (pixbuf);
+  pixels = gdk_pixbuf_get_pixels (pixbuf);
   width = gdk_pixbuf_get_width (pixbuf);
   height = gdk_pixbuf_get_height (pixbuf);
+  bpp = gdk_pixbuf_get_n_channels (pixbuf);
   rowstride = gdk_pixbuf_get_rowstride (pixbuf);
-  
+
+#define DITHER_COL(OFFS, BITS, MASK)                                             \
+          dithered = ((gint)gpixels[x*bpp + OFFS] + (rand()&MASK)) & (~(MASK));  \
+          dithered = dithered | dithered>>BITS;                                  \
+          if (dithered<0) dithered=0;                                            \
+          if (dithered>255) dithered=255;                                        \
+          gpixels[x*bpp + OFFS] = dithered;
+
   for (y=0;y<height;y++)
     {
-      pixit = gpixels + rowstride * y;
-    
-      /* set dither error to 0 for the beginning of a new line */
-      gint dither_error_red = 0;
-      gint dither_error_green = 0;
-      gint dither_error_blue = 0;
-      /* new line, dither each pixel */
+      guchar *gpixels = pixels + rowstride*y;
       for (x=0;x<width;x++)
         {
           gint dithered;
-          // RED - 5 bits
-          dithered = ((gint)(*pixit) + dither_error_red) & (~(7));
-          if (dithered<0) dithered=0;
-          if (dithered>255) dithered=255;
-          dither_error_red -= dithered - *pixit;
-          *(pixit++) = dithered;
-          // GREEN - 6 bits
-          dithered = ((gint)(*pixit) + dither_error_green) & (~(3));
-          if (dithered<0) dithered=0;
-          if (dithered>255) dithered=255;
-          dither_error_green -= dithered - *pixit;
-          *(pixit++) = dithered;
-          // BLUE - 5 bits
-          dithered = ((gint)(*pixit) + dither_error_blue) & (~(7));
-          if (dithered<0) dithered=0;
-          if (dithered>255) dithered=255;
-          dither_error_blue -= dithered - *pixit;
-          *(pixit++) = dithered;
-          // skip alpha
-          pixit++;
+          DITHER_COL(0, 5, 7) // RED - 5 bits
+          DITHER_COL(1, 6, 3) // GREEN - 6 bits
+          DITHER_COL(2, 5, 7) // BLUE - 5 bits
         }
     }
 }

Modified: projects/haf/trunk/hildon-theme-tools/src/dither.c
===================================================================
--- projects/haf/trunk/hildon-theme-tools/src/dither.c	2009-06-08 10:01:09 UTC (rev 18647)
+++ projects/haf/trunk/hildon-theme-tools/src/dither.c	2009-06-08 11:09:08 UTC (rev 18648)
@@ -61,10 +61,7 @@
                 return 1;
         }
         
-        g_print ("Dithering %s.\n", input_file);
         save_pixbuf (pixbuf, output_file, TRUE);
-        
-        gdk_pixbuf_unref (pixbuf);
 
         return 0;
 }