Video Thumbnail Out of Sync

[Dougal666]

The fewer issues I have to read, the more new features I will have time to implement, so I ask that you please try these things first

• Try with the newest version from GitHub (also it might have already been fixed in latest nightly build)
• Read the documentation and FAQ, Known issues, Troubleshooting
• Search for your problem under Issues or Discussions
• This problem happens with all kinds of files that I try. For problem only with a particular file or type, use this other form instead

Operating System

Windows 11

Steps to reproduce

I've seen all the "LLC cutting at the wrong place" threads and I think you missed the source of the problem.

I've cut hundreds of HDTV streams with LLC and the way I do it is this:

• Find cut points with MPC, copy timecode
• Paste timecode into LLC

Every time I've done this, the video thumbnail showed the wrong position and I had to move about 15 frames back for it to show the right place. I assumed the problem with the timecode given by MPC.
The cuts never were exactly where I wanted, but I assumed it was because of the keyframe cutting.

Now, however, I tried cutting at the exact points I got from MPC (without moveing 15 frames back)... and it cut at the places I wanted.

This means that LLC/ffmpeg cuts at the right timecode and the video thumbnail is out of sync by about 15 frames.

So your "ffmpeg cuts 20 frames too early" is actually the result of you giving it the wrong timecode because of the thumbnail showing 15 frames forward...

Expected behavior

Thumbnail should correspond to correct timecode.

Actual behavior

Thumbnail doesn't correspond to timecode...

Share log from developer tools

No response

[mifi]

So your "ffmpeg cuts 20 frames too early" is actually the result of you giving it the wrong timecode because of the thumbnail showing 15 frames forward...

Where does 20 frames come from? Not sure what you mean by this but LosslessCut doesn't subtract 20 or 15 frames from the segment times in the UI. LosslessCut sends those exact times to ffmpeg. What ffmpeg does internally depends on the particular file, it's audio/video tracks, codecs, keyframes, cutting mode, and many other settings. Not sure what change you want exactly. You can try to enable/disable keyframe cut mode and see if it makes a difference.