not scanning entire video file

[JoeWelling]

I'm wanting to scan very large files (almost 2 gig in size--roughly 8 hours long each) in -so mode. DVR-scan default settings with -so gives me just what I want, but when I run it, it only scans about the first 20% of the file, i.e. the first c. 200,000 frames out of about 864,000 frames. My understanding is that the default -st and -et settings are for the entire file.

I tried using -st and -et to specify a small range beginning at frame 300,000, and it reported 0% and 0 frames scanned.

What am I doing wrong?

[Breakthrough]

Hey @JoeWelling;

Does this happen with every source file you're using, or just a few in particular? Could you try re-encoding the video to see if that helps resolve the issue?

The current seeking implementation can be improved as per Breakthrough/PySceneDetect#98, but I doubt this is causing the issue you're seeing. It's possible that the video somehow ends prematurely due to file corruption, so I'd recommend trying to re-encode this particular file first to see if that's the cause or not.

Let me know how that works out so we can proceed, thank you!

[JoeWelling]

Thanks for the response.

I tried it on several of these big video files, with the same result. It never got beyond about 1 hr 54 minutes (around 212,000 frames). The video files themselves are not corrupted: I can play them all the way through.

I re-encoded the files, and in doing so inadvertently downsampled to 6.99 frames/second rather than the original 30 fps. The result was files that had the entire c. 8 hrs in right around 200,000 frames.

DVR-scan was able to do scan them all the way through, and the reduced frame rate doesn't concern me for my purposes. So it works, but I'm not sure if that is because the videos are within the range DVR-scan was already able to handle or some other reason.

[Breakthrough]

Hey @JoeWelling;

Could I get some more information about your system? What operating system are you using? What version of DVR-Scan are you using? How did you install it? What version of OpenCV are you using?

Lastly, would it be possible for you to share a sample video exhibiting this behaviour with me? (If not, no worries - let's start with the previous questions however!)

[Breakthrough]

This should be fixed now, see #62 for details.