20.05.2020, 22:56
I’m finally back, it took me a while to try and understand and test out everything you pointed out. I’m far from an expert on many of the topics you clearly have profound knowledge on.
First, I checked my source and capture another VHS to the same container and same compression (AVI/Huffyuv) and they are in fact interlaced cfr and not vfr. Does AVI container even allow vfr? I was under the assumption it didn’t.
Second, I used ffmpeg and ffprobe to get the timecodes for each frame (I did it by hand on the Tik and Tok files by copying and pasting form VirtualDub status bar and it was a horrible experience) and the results were same ones you found, each frame is around 33.3667 [33-34], no major jumps or glitches. Is there a better approach to extract timecodes?
What I did found is that I have some in-between shots that caused frame drops during capture, that lead me to believe that was the cause of all problems, but:
I really appreciate your help Selur
First, I checked my source and capture another VHS to the same container and same compression (AVI/Huffyuv) and they are in fact interlaced cfr and not vfr. Does AVI container even allow vfr? I was under the assumption it didn’t.
Second, I used ffmpeg and ffprobe to get the timecodes for each frame (I did it by hand on the Tik and Tok files by copying and pasting form VirtualDub status bar and it was a horrible experience) and the results were same ones you found, each frame is around 33.3667 [33-34], no major jumps or glitches. Is there a better approach to extract timecodes?
What I did found is that I have some in-between shots that caused frame drops during capture, that lead me to believe that was the cause of all problems, but:
- The master AVI file plays in-sync even with those issues.
- The sample files don’t have any frame drops and when I appended them together on a file over 2h the audio drifts when encoded to H.264 with or without any kind of filtering (simple or bob deinterlace) but no so when they are left in their original AVI container.
- I can apply QTGMC bob on Hybrid with no audio drift problems, but it has to be kept as an FFvHuff AVI which I can later encode to H.264 using Handbreak, AviDemux or ffmpeg… but why? Why does AVI works, isn’t audio and video being handled separately like with MKV H.264?
I really appreciate your help Selur