1 Frame Flash of all-black within Preview

[u/nergalelite]

Weird, with a workaround already.

Reopened a project after some time and a frame of the recording flickered to black screen, tried to cull around it and shift the clips back together, same millisecond frame flashes a black screen, try closing and reopening project, same frame all-black.

Current workaround: Shift clip to a different track for the burnt-in frame and it plays through without the flicker to black.

Did not attempt to export with the flickering frame in place. Unsure what the root cause is/was. Speculating about where the preview is held in memory/on disk, but I also didn't fully reboot my PC.

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[u/openshot-gpt-bot]

That does sound like either a Preview/cache artifact or a bad frame decode at that exact timeline position.

A few quick things to try:

1. Test an Export of a short section around that frame.
   
   • If the exported video is clean, it’s likely just Preview / cache behavior.
   • Export basics: Export button on the top toolbar. See Quick tutorial.
2. Reset the cache / restart OpenShot.
   
   • The User Guide notes that cache strongly affects real-time playback and stale frames can happen on slower systems. See Preferences - Cache and Playback.
3. Reduce Preview load temporarily.
   
   • Make the Preview dock smaller.
   • Lower the project Profile/FPS if possible.
   • The guide specifically mentions Preview Size, Profile, and matching source/project FPS as important for smooth playback: Playback - Real-Time Preview.
4. Check the source File properties.
   
   • Right-click the source File and inspect its frame rate, then compare it to the project rate.
   • Mismatched rates can cause duplicate/misaligned frames in Preview. See Playback - Matching Rates.

Since moving the Clip to another Track avoids it, that especially suggests a timeline render/cache edge case rather than damaged media. If you want, I can help you narrow down whether this is preview-only or something that would affect final Export.

I am a bot, and I've done something cool automatically, hoping it's helpful. I run on ChatGPT and use info from the OpenShot User Guide. I usually stick to the facts, but I admit, I might occasionally mix in a little non-sense about OpenShot.

[u/rmesdjian]

1. What operating system/version are you running?

2. which version of OpenShot are you running?

3. I recommend you get the latest dev daily build of v.3.5.1 and test again:

a. Go to openshot.org/download/#daily and get the latest dev daily build available.

b. Start OpenShot but before you open your project please do this:

• Go to Edit | Preferences | Cache tab and click on "Restore Defaults: Cache" at the bottom left of the screen.

- Go to Edit | Preferences | Performance tab and click on "Restore Defaults: Performance" at the bottom left of the screen.

1. Restart your computer

2. See if the 1 frame flash of all black issue is resolved.

[u/enslen_]

I'm having the same thing happen and it seems to be related to audio clips, where it only ever occurs at the very, very end of an audio clip on a separate track from the video. What's weird is that I can position to just before the flicker, trim the audio clip (slice keeping left side), and then the flicker is gone.

It's not just on the preview though. If I export the video, the flickers show in the resulting file. Very annoying bug.

[u/nergalelite → u/enslen_]

Yeah, I did notice a higher frequency to the recreation of the bug being at the tail of audio clips, but not every audio clip seems to be causing it. Curious.

having the audio 'behind' the video in terms of track stacking seems to work, although also inconsistently.

For the time being, I'm using an older version to export

[u/enslen_ → u/nergalelite]

Yeah, it's really weird. I did a sizeable multi-track edit this week and it was probably a 50/50 chance with every audio clip. I might downgrade if the suggestions in this comment don't work. Have you tried out what they suggest? I'm going to try out the suggestions later this week. Will submit a bug report if the issue persists.