The current release of ffdshow-tryout (v1.2.4422) mentions "multi-threaded decoding for FFv1". Multi-threading support for FFv1 required the development of a new bitstream format for FFv1, called "FFv1.2".
Before any official release of FFv1.2, it was superseded by its successor FFv1.3.
So, if you support multi-threaded decoding of FFv1, I assume it is necessary to support FFv1.3?
ffdshow has multi-threaded decoding, not encoding.
Also, ffdshow is no longer under active development, so expect no changes in this regard.
I never assumed encoding.
However, I thought that multithreading decoding of FFv1 would require its newer bitstream (FFv1 >= version 2).
About ffdshow no longer being actively developed:
ffdshow has been dead for years, but are you telling me that ffdshow-tryout is also being abandoned? :(
Are there any alternatives?