Seeking back and forward a frame does not update the preview window (3.65)

[dmn001]

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

When pressing , and . to go back and forwards between frames, the preview window does not update at all.

Reverting to 3.64 as a workaround.

maybe related to: #2369 and #2364

Expected behavior

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Actual behavior

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Share log from developer tools

No response

[mifi]

does this apply to all video file types you try? you're just seeing the first frame and nothing else?

[dmn001]

it seems to be worst with h264/mkv, and it also seems to be less responsive on mp4, although it does show the frames but less smoothly than before.

i can see the frames if i click or drag on the timeline using the mouse. i can see the frames update when pressing left/right arrow and going back/forward 1 second. however, i cannot see any changes when i press foward back one frame. when i hold down , or ., the frames update around every second.

[mifi]

Ok, strange. I'm not seeing this problem on MacOS

[zwei7]

Can confirm, the single frame scrubbing to go back < and > forth became broken with my h264/mkv files. In fact it now says the file format (h264/mkv) is not supported and has to convert to a supported format and use the ultra slow ffmpeg assisted playback.

Reverting back to 3.64 works perfectly.

Files are made with OBS in game capture mode

Setting 1

• Program: OBS Studio
• Video Encoder: x264
• Resolution: 3940x2160p / Framerate: 60 fps
• Rate Control: CRF / CRF: 20
• Preset: Ultrafast / Profile: High
• Audio: AAC / 320 kbps

Setting 2

• Program: OBS Studio
• Video Encoder: NVDIA NVENC H.264
• Resolution: 3940x2160p / Framerate: 60 fps
• Rate Control: Constant QP: 20
• Keyframe Interval: 0 s
• Preset: P1 Fastest (Lowest Quality)
• Tuning: High Quality
• Multipass Mode: Two Passes (Quarter Resolution)
• Look-ahead: Check-marked
• Adaptive Quantization: Check-marked
• B-Frames = 2

3.64 supports both my OBS settings 1+2, no need to convert to a supported format.
3.64 can scrub through single frames, preview window updates.
3.65 can only support scrubbing keyframe to keyframe in both OBS settings, preview window updates.

I think this is a 3.65 issue since I opened the same video file in 3.64.

[mifi]

is the problem related to ffmpeg-assisted playback or natively supported files? edit: ah I see that it does convert to supported format. is it possible to share a file that worked on 3.64 but now shows this problem on 3.65?

[zwei7]

is the problem related to ffmpeg-assisted playback or natively supported files? edit: ah I see that it does convert to supported format. is it possible to share a file that worked on 3.64 but now shows this problem on 3.65?

Sure here you go, made with these settings

Program: OBS Studio
Video Encoder: NVDIA NVENC H.264
Resolution: 3940x2160p / Framerate: 60 fps
Rate Control: Constant QP: 20
Keyframe Interval: 0 s
Preset: P1 Fastest (Lowest Quality)
Tuning: High Quality
Multipass Mode: Two Passes (Quarter Resolution)
Look-ahead: Check-marked
Adaptive Quantization: Check-marked
B-Frames = 2

https://www.mediafire.com/file/ypgq3vzz3s25d7q/2025-03-28_22-16-27.mkv/file

[mifi]

Thanks. For me (macOS) I'm not getting any message that the format is not supported, however I can observe the seeking issue, need to investigate further.

[zwei7]

I am using your Windows version of lossless cut on windows 10 x64.

[mifi]

I can reproduce with certain videos. It seems to have broken in Electron v33.0.0 and later (works as of v32.3.3). See also super issue #2392