Time marquee + screen filter for automated screenshots

[evean]

Help me, brains trust. You're my last hope. I have few technical skills, but am capable at educating myself through intense googling, so please forgive me if I get any terms wrong.

I have successfully learned how to automate screenshots with screen filter function, and added the time extension for a time marquee on screen. However, (surprising no one here, I'm sure) they do not work together. I want the end result to be a folder full of frame-by-frame screenshots with the time to the millisecond embedded in the image, and preferably in the filename as well.

I'm willing to jump through any hoops to find a workaround, as I realise that VLC just won't be able to do this. I can't find any third party apps to help, as the fastest they screenshot is per second. My videos are 25 fps so per second isn't nearly enough detail for my purposes. I've tried screen recording the video with the time overlay as it's playing, but the lag is just.....not good. I'd be happy to create a new file with the timestamp "hard burned" in the file, but I can't figure out how to do it.

I've been all through this forum and I see others having the same issue over the years. Has anyone got any ideas at all I can try?

[For anyone wondering, the video is data for my PhD, and the still images with timestamps will be invaluable to use in publications etc, so I have a library of these and don't have to go create them / lose track of them. I study things like gesture and gaze, looking very specific timing. The videos are only a couple of minutes long. This learning curve will totally be worth it if I can get there, it will save me bucketloads of time in the future if I can only get it to work :') ]

[fkuehne]

Can you share your command-line so we can see where it fails? Technically, it should be possible to do.