– Merged with latest release
– Added hq2x/hq3x filters
– Fixed some bugs in scale3x filter
– Changed linebuffer to drop samples on write to support scaling filters
I like the way the hqx filter turned out. It’s heavily based on the fpganes implementation with updates to support hq3x. There’s also a temporary debug “diff” filter mode to help see what the hqx diff function output looks like. Pixels still flicker with the scaling filters, but I have some ideas on how to fix that now that I know what the problem is.
With the diff mode it’s easy to see why the pixels flicker. Even with static images there is some temporal change in pixels across frames. Since the diff function has a sharp cutoff any comparison that is near that boundary will cause it to bounce between different blending functions and any large changes in the output pixel will result in the flicker. I think I know how to fix it for the scale filter, but hqx will require some more thought.