in-loop deblocking for codecs other than H.264?

[TomB]

I just converted a few videos from H.264 to VP9 and in certain scenes got a lot of blocking, even turning the bitrate up to ridiculous levels.

I have discovered why: The blocking exists in the original video. If I go to tools > preferences > input/codecs and set "Skip H.264 in-loop deblocking filter" to "All", I see exactly the same blocking in the video. Clearly the encoder is working fine, it's just encoding the same blocks that exist in the H.264 video. However, when playing the H.264 version of the video, the deblocking filter is applied and the video looks much better.

As per the lablel, it looks like this only applies to H.264 videos. Is it possible to apply the same kind of deblocking filters to other video formats? e.g VP9.