Modified shrink such that it now will work with Images that have a Co…

…mplexPixel type and return the same type of image. This seems more intuitive and allow users to use it with GrayImages and get GrayImages back. If the user want to use it specifically with Complex values, they will already have a ComplexImage and thus it is a non issue and the type does not need to be coerced.

Data/Image/Boxed.hs

@@ -163,6 +163,7 @@ instance BinaryPixel Gray where
 instance CI.ComplexPixel Gray where
   type Value Gray = Double
   toComplex i =  i C.:+ 0.0
+  fromComplex (r C.:+ i) = r
 
 instance Monoid Gray where
   mempty = 0.0
@@ -279,6 +280,7 @@ instance DisplayFormat ComplexImage where
 instance CI.ComplexPixel Complex where
   type Value Complex = Double
   toComplex = id
+  fromComplex = id
 
 complexImageToColorImage :: ComplexImage -> ColorImage
 complexImageToColorImage img = fmap rgb img where
@@ -593,8 +595,7 @@ complexImageToRectangular = CI.complexImageToRectangular
    
  -}
 shrink :: (Image img,
-           CI.ComplexPixel (Pixel img),
-           CI.Value (Pixel img) ~ Double) => Double -> img -> ComplexImage 
+           CI.ComplexPixel (Pixel img)) => (CI.Value (Pixel img)) -> img -> img
 shrink = CI.shrink
 
 {-| Given an image whose pixels can be converted to a complex value, 

Data/Image/Complex.hs

@@ -46,6 +46,7 @@ import qualified Data.Vector as V
 class RealFloat (Value px) => ComplexPixel px where
   type Value px :: *
   toComplex ::  px -> C.Complex (Value px)
+  fromComplex :: C.Complex (Value px) -> px
 
 {-| Given a positive integer m, a positive integer n, and a function 
     returning a pixel value, makeFilter returns an image with m rows 
@@ -274,12 +275,10 @@ complexImageToRectangular img = (realPart img, imagPart img)
    
  -}
 shrink :: (Image img,
-           ComplexPixel (Pixel img), 
-           Image img',
-           Pixel img' ~ C.Complex (Value (Pixel img))) => (Value (Pixel img)) -> img -> img'
+           ComplexPixel (Pixel img)) => (Value (Pixel img)) -> img -> img
 shrink x img@(dimensions -> (rows, cols)) = 
   makeImage rows cols shrink' where
-    shrink' r c = helper px where
+    shrink' r c = fromComplex . helper $ px where
       px = toComplex . ref img r $ c
       helper px
         | (C.magnitude px) < x = 0.0 C.:+ 0.0

changes.txt

@@ -1,10 +1,13 @@
-Version #: 0.2.1.5
+Version #: 0.3.1.5
            ^ ^ ^ ^
            | | | --- Bug fixes / improvements to existing code
            | | ----- New functions / features
            | |------ Break in backwards compatibilty
            |-------- Change in stability
 
+unm-hip-0.3.1.5: 
+  - Modified shrink such that it now will work with Images that have a ComplexPixel type and return the same type of image. This seems more intuitive and allow users to use it with GrayImages and get GrayImages back. If the user want to use it specifically with Complex values, they will already have a ComplexImage and thus it is a non issue and the type does not need to be coerced.
+
 unm-hip-0.2.1.5
  - fixed a bug in normalize that was producing images with NaN pixel values
  - fixed a bug in shrink that was producing an infinite loop. Resulting in the type signature changing

unm-hip.cabal

@@ -1,5 +1,5 @@
 Name:              unm-hip
-Version:       	   0.1.1.5
+Version:       	   0.3.1.5
 License:           GPL
 License-File:      LICENSE
 Author:	           Joseph Collard, Stephen Patel, Lance Williams
@@ -11,7 +11,7 @@ Description:       The University of New Mexico's Haskell Image Processing libra
                    .
                    [Changes]
                    .
-                     * Fixed a bug in normalize that was producing images with NaN pixel values
+                    * Modified shrink such that it now will work with Images that have a ComplexPixel type and return the same type of image. This seems more intuitive and allow users to use it with GrayImages and get GrayImages back. If the user want to use it specifically with Complex values, they will already have a ComplexImage and thus it is a non issue and the type does not need to be coerced.
 Cabal-Version:     >= 1.6
 Build-Type:        Simple