Hi,
This patch, committed, optimizes filtering in
java.awt.image.BandCombineOp.
With this patch, running on cacao, our filtering is faster (!) than
Sun's for small images (under ~ 150x150 pixels), but doesn't scale as
well to larger images.
One catch is that the Op now does int arithmetic, instead of using
floats (floats will be rounded and cast). Using floats as image sample
datatypes is pretty rare though (I think), and I've added a note in our
API documentation about this (Sun's API states, "... built-in image
processing operators may not operate on all possible sample types, but
generally will work for unsigned integral samples of 16 bits or less.").
I think the speed tradeoff is worth it.
Regards,
Francis
2006-09-13 Francis Kung <[EMAIL PROTECTED]>
* java/awt/image/BandCombineOp.java: Updated documentation.
(filter(Raster, WritableRaster)): Use int arrays, and added simple
cache.
