VC1 Interlaced Fix

[thePoet]

libav has fixed a number of bugs related to VC-1 interlaced decoding. Out of curiosity, I spent some time today getting handbrake, and libhb, to build against the unpatched master code of libav. I was pleasantly surprised that it resulted in a handbrake that was able to re-encode a number of videos it had not been able to handle properly in the past. I have also removed the blu-ray vc1 interlaced check.

Typically, I would put together a patch and submit this code, however, since this requires a significant update of libav in handbrake, which will have a significant impact across the application, and I was intentionally skipping all the patches that are normally part of the build process, it seems that a fix of this order requires more than a simple patch, and probably isn't something the dev team wants an outsider trying to push through. However, if there is anything I can do to help move this feature along so that it is ready for the next release, please let me know.

[Deleted User 11865]

You could always test https://reviews.handbrake.fr/r/559/

It removes all patches except QSV, and gets rid of deprecated API usage as much as possible.

[thePoet]

Thanks for pointing that out. I'll pull the patch and test it.

I did notice in my build that, while everything looked okay at first glance, certainly better than it looked before, the decoder is only sending half the frames that are expected, so my output ends up being around 15 fps instead of 30.