For some MKV streams a GOP step produces a corrupted picture.
We have a workaround for streams with successive IDR frames with the same idr_pic_id, but this was being applied only for ES streams. When applying it to all container types, the problem is fixed.
I will release this along with the MKV re-design work.
GOP step error for some MKV streams
GOP step error for some MKV streams
Turns out this is not related to successive IDRs with the same idr_pic_id, and I imagined that it was fixed. Nevertheless that should be fixed. The real reason was very complex and difficult to find but I found it!
GOP step error for some MKV streams
After I got forward stepping working reliably I found that backward stepping was hosed. Reliable GOP navigation is important to set accurate project ranges, of course. Anyway, I just got that fixed this morning and as I mentioned in another post will release a candidate version very soon, maybe today.