Artifact: MPEG-2 truncation(?) vertical streaking/smearing

[ryanfb]

I have an artifact I've seen in the wild a few times, and somewhat reliably from my own capture setup, where an MPEG-2 frame gets vertically smeared. I assume this is due to truncated data (the capture setup where I see it most often is an HDHomeRun Prime, which lets you record an MPEG-2 TS from cable by giving it a duration - I think sometimes the duration doesn't line up exactly with an MPEG-2 frame, resulting in this error. Unfortunately I don't keep all the original TS files so I don't have a raw TS to verify this).

Some examples:
https://twitter.com/neural_tv/status/807783247748939776
https://twitter.com/tv_sounds/status/836294900106809344

[ablwr]

I've seen this too when doing some intentional file fuzzing, here is William Gibson looking 😵 SURPRISED 😵

[ablwr]

That theory makes sense to me, or the live encoding trying to keep up with the time and skipping to the next frame prematurely, but repeating the last line.

I will open this up as a ✨ NEW ARTIFACT ✨ , thank you very much! Maybe more people will have more details.

[metacynicv2]

Interesting - have we only seen this related to MPEG-2?

There's a similar-looking video clog artifact for a Umatic tape that I was always wondering was really a TBC error (looks a little digity) https://bavc.github.io/avaa/artifacts/video_head_clog.html