Fun with YADIF and QTGMC

[Katie Boundary]

In case anyone is wondering, QTGMC does not handle fades and certain other kinds of content well...

https://i.imgur.com/zfYuCof.jpeg

[hello_hello]

What QTGMC settings did you use?
It's probably related to QTGMC's shimmer repair.
According to flossy_cake, Rep0=13 works well for repairing the sort of artifacts QTGMC can create when de-interlacing animation. Maybe it'd work well for that sort of thing too.
https://forum.doom9.org/showthread.php?p=2025150#post2025150

[DTL]

Yes - that fades may cause too high SAD between static blocks in sequence of frames. This may cause 2 types of issues:
1. Scenecut trigger activation (controlled by thSCD1 param)
2. Stopping of any blends in denoise parts (protection by thSAD param value) and also stopping of motion compensation in MCompensate().

In worst case MCompensate() expect to output input (src) frame unchanged. But we see some spatially shifted blocks - it looks like bad MVs are produced and used (in MCompensate ? or also at MDegrain ?).

To test it first any denoise with MDegrainX need to be disabled. And next possible attempt is to play with thSAD and thSCD1 params for motion estimation and motion compensation to see how they change result.

While we do not have lighting estimation and compensation in mvtools - the simple global frame fades will produce significant issues for motion estimation/compensation based on simple SAD.