new function that swaps the vertical and horizontal axis for the saved

2007-08-24  Raphael Quinet  <raphael@gimp.org>

	* plug-ins/jpeg/jpeg-settings.c (jpeg_swap_original_settings): new
	function that swaps the vertical and horizontal axis for the saved
	subsampling parameters and quantization tables.

	* plug-ins/jpeg/jpeg-exif.c (jpeg_exif_rotate): swap the saved
	settings when the image is rotated.  Fixes bug #466593.

	* devel-docs/release-howto.txt: added note about having admin
	access to Bugzilla and to the news section on www.gimp.org.

svn path=/trunk/; revision=23370

ChangeLog

@@ -1,3 +1,15 @@
+2007-08-24  Raphaël Quinet  <raphael@gimp.org>
+
+	* plug-ins/jpeg/jpeg-settings.c (jpeg_swap_original_settings): new
+	function that swaps the vertical and horizontal axis for the saved
+	subsampling parameters and quantization tables.
+
+	* plug-ins/jpeg/jpeg-exif.c (jpeg_exif_rotate): swap the saved
+	settings when the image is rotated.  Fixes bug #466593.
+
+	* devel-docs/release-howto.txt: added note about having admin
+	access to Bugzilla and to the news section on www.gimp.org.
+
 2007-08-24  Raphaël Quinet  <raphael@gimp.org>
 
 	* tools/pdbgen/pdb/selection.pdb: fixed incorrect description of

devel-docs/release-howto.txt

@@ -70,7 +70,7 @@
 
  ( ) Check out or update the 'gimp-web' module and change
      downloads/index.htrw.  Commit this change, the web server should
-     then update itself soon (usually less than half an hour).
+     then update itself soon (usually less than an hour).
 
  ( ) Bump the version number in configure.in and commit this change.
 

plug-ins/jpeg/jpeg-exif.c

@@ -18,8 +18,8 @@
 
 /*
  * EXIF-handling code for the jpeg plugin.  May eventually be better
- * to move this stuff into libgimpbase and make it available for
+ * to move this stuff into libgimpbase or a new libgimpmetadata and
- * other plugins.
+ * make it available for other plugins.
  */
 
 #include "config.h"
@@ -45,6 +45,7 @@
 #include "gimpexif.h"
 
 #include "jpeg.h"
+#include "jpeg-settings.h"
 
 #include "libgimp/stdplugins-intl.h"
 
@@ -248,20 +249,24 @@ jpeg_exif_rotate (gint32 image_ID,
 
     case 5:  /* flipped diagonally around '\'    */
       gimp_image_rotate (image_ID, GIMP_ROTATE_90);
+      jpeg_swap_original_settings (image_ID);
       gimp_image_flip (image_ID, GIMP_ORIENTATION_HORIZONTAL);
       break;
 
     case 6:  /* 90 CW                            */
       gimp_image_rotate (image_ID, GIMP_ROTATE_90);
+      jpeg_swap_original_settings (image_ID);
       break;
 
     case 7:  /* flipped diagonally around '/'    */
       gimp_image_rotate (image_ID, GIMP_ROTATE_90);
+      jpeg_swap_original_settings (image_ID);
       gimp_image_flip (image_ID, GIMP_ORIENTATION_VERTICAL);
       break;
 
     case 8:  /* 90 CCW                           */
       gimp_image_rotate (image_ID, GIMP_ROTATE_270);
+      jpeg_swap_original_settings (image_ID);
       break;
 
     default: /* can't happen                     */

plug-ins/jpeg/jpeg-settings.c

@@ -31,14 +31,15 @@
  * Additional data following the quantization tables is currently
  * ignored and can be used for future extensions.
  *
- * The parasite contains the original subsampling for each component
+ * In order to improve the compatibility with future versions of the
- * instead of saving only the subsampling type as used by the jpeg
+ * plug-in that may support more subsampling types ("subsmp"), the
- * plug-in ("subsmp") in order to improve the compatibility with
+ * parasite contains the original subsampling for each component
- * future versions of the plug-in that may support more subsampling
+ * instead of saving only one byte containing the subsampling type as
- * types.  The same applies to the other settings: for example, up to
+ * used by the jpeg plug-in.  The same applies to the other settings:
- * 4 quantization tables will be saved in the parasite even if the
+ * for example, up to 4 quantization tables will be saved in the
- * current code cannot restore more than 3 of them (4 tables may be
+ * parasite even if the current code cannot restore more than 2 of
- * needed by unusual JPEG color spaces such as JCS_CMYK or JCS_YCCK).
+ * them (4 tables may be needed by unusual JPEG color spaces such as
+ * JCS_CMYK or JCS_YCCK).
  */
 
 #include "config.h"
@@ -280,14 +281,13 @@ jpeg_restore_original_tables (gint32    image_ID,
       if (src_size >= 4)
         {
           src = gimp_parasite_data (parasite);
-          src += 2;
+          num_components = src[2];
-          num_components   = *src++;
+          num_tables     = src[3];
-          num_tables       = *src++;
 
           if (src_size >= (4 + num_components * 2 + num_tables * 128)
               && num_tables == num_quant_tables)
             {
-              src += num_components * 2;
+              src += 4 + num_components * 2;
               quant_tables = g_new (guint *, num_tables);
 
               for (t = 0; t < num_tables; t++)
@@ -310,3 +310,83 @@ jpeg_restore_original_tables (gint32    image_ID,
     }
   return NULL;
 }
+
+
+/**
+ * jpeg_swap_original_settings:
+ * @image_ID: the image that may contain original jpeg settings in a parasite.
+ *
+ * Swap the horizontal and vertical axis for the saved subsampling
+ * parameters and quantization tables.  This should be done if the
+ * image has been rotated by +90 or -90 degrees or if it has been
+ * mirrored along its diagonal.
+ */
+void
+jpeg_swap_original_settings (gint32 image_ID)
+{
+  GimpParasite *parasite;
+  const guchar *src;
+  glong         src_size;
+  gint          num_components;
+  gint          num_tables;
+  guchar       *new_data;
+  guchar       *dest;
+  gint          t;
+  gint          i;
+  gint          j;
+
+  parasite = gimp_image_parasite_find (image_ID, "jpeg-settings");
+  if (parasite)
+    {
+      src_size = gimp_parasite_data_size (parasite);
+      if (src_size >= 4)
+        {
+          src = gimp_parasite_data (parasite);
+          num_components = src[2];
+          num_tables     = src[3];
+
+          if (src_size >= (4 + num_components * 2 + num_tables * 128))
+            {
+              new_data = g_new (guchar, src_size);
+              dest = new_data;
+              *dest++ = *src++;
+              *dest++ = *src++;
+              *dest++ = *src++;
+              *dest++ = *src++;
+              for (i = 0; i < num_components; i++)
+                {
+                  dest[0] = src[1];
+                  dest[1] = src[0];
+                  dest += 2;
+                  src += 2;
+                }
+              for (t = 0; t < num_tables; t++)
+                {
+                  for (i = 0; i < 8; i++)
+                    {
+                      for (j = 0; j < 8; j++)
+                        {
+                          dest[i * 16 + j * 2]     = src[j * 16 + i * 2];
+                          dest[i * 16 + j * 2 + 1] = src[j * 16 + i * 2 + 1];
+                        }
+                    }
+                  dest += 128;
+                  src += 128;
+                  if (src_size > (4 + num_components * 2 + num_tables * 128))
+                    {
+                      memcpy (dest, src, src_size - (4 + num_components * 2
+                                                     + num_tables * 128));
+                    }
+                }
+              gimp_parasite_free (parasite);
+              parasite = gimp_parasite_new ("jpeg-settings",
+                                            GIMP_PARASITE_PERSISTENT,
+                                            src_size,
+                                            new_data);
+              g_free (new_data);
+              gimp_image_parasite_attach (image_ID, parasite);
+            }
+        }
+      gimp_parasite_free (parasite);
+    }
+}