[libcvd-members] libcvd/cvd image_convert.h

[Edward Rosten]

CVSROOT:        /cvsroot/libcvd
Module name:    libcvd
Changes by:     Edward Rosten <edrosten>        07/03/28 21:40:15

Modified files:
        cvd            : image_convert.h 

Log message:
        Lazy image_convert function. Can now do:
        
        Image<byte> a;
        Image<byte> b;
        ...
        b = convert_image(a);

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/libcvd/cvd/image_convert.h?cvsroot=libcvd&r1=1.10&r2=1.11

Patches:
Index: image_convert.h
===================================================================
RCS file: /cvsroot/libcvd/libcvd/cvd/image_convert.h,v
retrieving revision 1.10
retrieving revision 1.11
diff -u -b -r1.10 -r1.11
--- image_convert.h     15 May 2006 15:58:59 -0000      1.10
+++ image_convert.h     28 Mar 2007 21:40:15 -0000      1.11
@@ -80,7 +80,6 @@
   /// @param Conv The conversion to use
   /// @param from The image to convert from
   /// @ingroup gImageIO
-  
   template<class D, class Conv, class C> Image<D> convert_image(const 
BasicImage<C>& from)
   {
     Image<D> to(from.size());
@@ -100,7 +99,6 @@
   /// @param C The source image pixel type
   /// @param from The image to convert from
   /// @ingroup gImageIO
-  
   template<class D, class C> Image<D> convert_image(const BasicImage<C>& from)
   {
     Image<D> to(from.size());
@@ -117,7 +115,6 @@
   /// @param C The source image pixel type
   /// @param from The image to convert from
   /// @ingroup gImageIO
-
   template<class D1, class D2, class C> std::pair<Image<D1>, Image<D2> > 
convert_image_pair(const BasicImage<C>& from)
   {
     std::pair<Image<D1>, Image<D2> > to(Image<D1>(from.size()), 
Image<D2>(from.size()));
@@ -126,6 +123,48 @@
     return to;
   }  
        
+
+  #ifndef DOXYGEN_IGNORE_INTERNAL
+  namespace Internal
+  {
+       template<class C> class ImageConverter{};
+       template<class C>  struct ImagePromise<ImageConverter<C> >
+       {
+               ImagePromise(const BasicImage<C>& im)
+               :i(im)
+               {}
+
+               const BasicImage<C>& i;
+               template<class D> void execute(Image<D>& j)
+               {
+                       j.resize(i.size());
+                       convert_image(i, j);
+               }
+       };
+  };
+  template<class C> Internal::ImagePromise<Internal::ImageConverter<C> > 
convert_image(const BasicImage<C>& c)
+  {
+    return Internal::ImagePromise<Internal::ImageConverter<C> >(c);
+  }
+  #else
+       ///Convert an image from one type to another using the default.
+       ///Type deduction is automatic, and D does not need to be specified. 
The following usage will work:
+       ///
+       /// \code
+       /// Image<byte> a;
+       /// Image<byte> b;
+       /// ...
+       /// b = convert_image(a);
+       /// \endcode
+       /// Note that this is performed using lazy evaluation, so convertion 
happens on evaluation of assignment.
+    /// @param D The destination image pixel type
+    /// @param C The source image pixel type
+    /// @param from The image to convert from
+       /// @return The converted image
+    /// @ingroup gImageIO
+       template<class D> Image<D> convert_image(const BasicImage<C>& from);
+
+  #endif
 }
 
 #endif