An advice? You use of parallel is pretty much pointless here. You kill all the performance with the use of
. You should not use these methods at all, unless you don't care of performance at all, or if you have to access very few pixels. If this is
, you should use
The MSDN help page on the first of the methods contains a short and very simple code sample.
With WPF, you need to use pretty similar approach with the class