Changeset 7625 for ImageMagick/branches/ImageMagick-6/magick/composite.c

Timestamp:

04/25/12 00:47:23 (13 months ago)

Author:

anthony

Message:

Fix Gaussian Filter which was causing problems with Variable Blur

File:

• ImageMagick/branches/ImageMagick-6/magick/composite.c (modified) (11 diffs)

ImageMagick/branches/ImageMagick-6/magick/composite.c

@@ -1646 +1646 @@
     return(MagickFalse);
   GetMagickPixelPacket(image,&zero);
+  exception=(&image->exception);
   destination_image=(Image *) NULL;
   amount=0.5;
@@ -1687 +1688 @@
         break;
       status=MagickTrue;
-      exception=(&image->exception);
       composite_view=AcquireVirtualCacheView(composite_image,exception);
       image_view=AcquireAuthenticCacheView(image,exception);
@@ -1783 +1783 @@
 
       /*
+        Blur Image by resampling.
+
         Blur Image dictated by an overlay gradient map: X = red_channel;
           Y = green_channel; compose:args =  x_scale[,y_scale[,angle]].
       */
       destination_image=CloneImage(image,image->columns,image->rows,MagickTrue,
-        &image->exception);
+        exception);
       if (destination_image == (Image *) NULL)
         return(MagickFalse);
       /*
-        Determine the horizontal and vertical maximim blur.
+        Gather the maximum blur sigma values from user.
       */
       SetGeometryInfo(&geometry_info);
@@ -1799 +1801 @@
         flags=ParseGeometry(value,&geometry_info);
       if ((flags & WidthValue) == 0 ) {
+          (void) ThrowMagickException(exception,GetMagickModule(),
+               OptionWarning,"InvalidGeometry","'%s' '%s'",
+               "compose:args",value);
           destination_image=DestroyImage(destination_image);
           return(MagickFalse);
         }
-      /* Width and height of ellipse.
-         Note: The Gaussian Filter uses a sigma = 0.5, so to compensate the
-         input sigma must be doubled to give a correct 'area to resample'.
+      /*
+        Users input sigma now needs to be converted to the EWA ellipse size.
+        The filter defaults to a sigma of 0.5 so to make this match
+        the elipse size needs to be doubled.
       */
       width=height=geometry_info.rho*2.0;
       if ((flags & HeightValue) != 0 )
         height=geometry_info.sigma*2.0;
-
-/* Hack -- this make gaussian work! -- But it is not needed for cubic! */
-width*=2.0; height*=2.0;
 
       /* default the unrotated ellipse width and height axis vectors */
@@ -1830 +1833 @@
           blur.y2=height*cos(angle);
         }
-      /* otherwise lets set a angle range and calculate in the loop */
+      /* Otherwise lets set a angle range and calculate in the loop */
       angle_start=0.0;
       angle_range=0.0;
@@ -1839 +1842 @@
         }
       /*
-        Blur Image by resampling.
-
-        FUTURE: this is currently broken, especially for small sigma blurs
-        This needs to be fixed to use a non-user filter setup that provides
-        far more control than currently available.
-
-        It should also be set to GaussianFilter, but it is not being effected
-        by ScaleResampleFilter() for some reason.
+        Set up a gaussian cylindrical filter for EWA Bluring.
+
+        FUTURE: Currently broken, small sigma blurs
+          (either goes to zero earily, or blurs on zero blurs)
+
+        Also need to prevent user 'expert' filter options overriding the
+        filter settings I am carfully setting up for image blurring.
       */
+      resample_filter=AcquireResampleFilter(image,exception);
+      SetResampleFilter(resample_filter,GaussianFilter,1.0);
+
+      /* do the variable blurring of each pixel in image */
       pixel=zero;
-      exception=(&image->exception);
-      resample_filter=AcquireResampleFilter(image,&image->exception);
-      SetResampleFilter(resample_filter,GaussianFilter,1.0);
       composite_view=AcquireVirtualCacheView(composite_image,exception);
       destination_view=AcquireAuthenticCacheView(destination_image,exception);
@@ -1876 +1879 @@
           1,exception);
         r=QueueCacheViewAuthenticPixels(destination_view,0,y,
-          destination_image->columns,1,&image->exception);
+          destination_image->columns,1,exception);
         if ((p == (const PixelPacket *) NULL) || (r == (PixelPacket *) NULL))
           break;
@@ -1960 +1963 @@
       */
       destination_image=CloneImage(image,image->columns,image->rows,MagickTrue,
-        &image->exception);
+        exception);
       if (destination_image == (Image *) NULL)
         return(MagickFalse);
@@ -2041 +2044 @@
       */
       pixel=zero;
-      exception=(&image->exception);
       image_view=AcquireVirtualCacheView(image,exception);
       composite_view=AcquireVirtualCacheView(composite_image,exception);
@@ -2061 +2063 @@
           1,exception);
         r=QueueCacheViewAuthenticPixels(destination_view,0,y,
-          destination_image->columns,1,&image->exception);
+          destination_image->columns,1,exception);
         if ((p == (const PixelPacket *) NULL) || (r == (PixelPacket *) NULL))
           break;
@@ -2214 +2216 @@
   midpoint=((MagickRealType) QuantumRange+1.0)/2;
   GetMagickPixelPacket(composite_image,&zero);
-  exception=(&image->exception);
   composite_view=AcquireVirtualCacheView(composite_image,exception);
   image_view=AcquireAuthenticCacheView(image,exception);