int64.org

ResampleHQ

Our eyes don't perceive light linearly. Twice the photons will not appear twice as bright. To account for this, colorspaces with small bit widths (all the ones in Avisynth) are gamma-compressed to give a more eye-friendly representation, ensuring bits are evenly distributed across all perceived intensities.

These gamma-compressed colors must be converted back to a linear colorspace prior to blending, or you get incorrect results. None of Avisynth's filters do this correctly. For rare scenes with a lot of sharp contrast this causes very pronounced errors. For most other scenes the errors are more subtle. It can also effect the quality of anti-aliasing on edges with a lot of contrast (such as in outline-heavy anime and cartoons).

ResampleHQ produces correct results using a high-precision 100% linear pipeline. Because colorspace conversion and resizing are often essentially the same thing, we can perform both operations at once for higher performance and better quality.

Contributing

ResampleHQ will always be free, but donations are still appreciated and will help me figure out what to spend my time on. Any small amount helps!

If you're a programmer and would like to contribute a patch, please email me.

Open Source

ResampleHQ is Open Source and distributed under a GNU General Public License v3.0. The source code can be viewed online or downloaded through Subversion:

svn co https://svn.int64.org/svnroot/int64/resamplehq resamplehq

ResampleHQ also uses Boost, another great piece of Open Source software.