This mod was created to expand the functionality. THX for the codes @msg7086 and @DJATOM!
Mod contains:

extended progress bar

y4m

- XLENGTH tag support

avisynth

- possibility to load external avisynth library

vapoursynth

- possibility to load external vapoursynth library

The original repository can be found at Bitbucket. Instructions on how to download and create the source can be found on the developer wiki.

X265 is an open source HEVC encoder. x265 is free to use under the GNU GPL and is also available under a commercial license.