[HELP] No preview window

[Miranda]

I'm trying to upscale an mp4 to ProRes, but I'm not able to view a preview. Any suggestions?

[Selur]

My guess is that's a problem with MCDegrainSharp the libmvtools.dll.
Try replacing libmvtools.dll with libmvtools_old.dll or update to latest dev.

Cu Selur

[Miranda]

I think it's a problem with the timecode. I'll try ignoring the file's timecode.

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Even without any filters it is still causing the preview window to not display. Tried ignore timecode, no luck.

Clip

[Selur]

Just loading the source and opening the Vapoursynth preview:
dgdecodenv => works
BestSource => works
BestSource + OpenCL/Vukan/CUDA/... => works
LibavSMASHSource => works
LWLibavSource => works
LWLibavSource + ... => works
ffms2 => works
(I used latest dev)

Cu Selur

[Miranda]

Tried the new dev version with no filters and still no preview window. I don't see a preview for any mp4 files, the wondow pops up quickly, displays just grey, then disappears. 

[Selur]

What happens if you:
1. check the Vapoursynth script
2. open vsViewer
3. copy the content of the Vapoursynth script into it
and press F5 ?

[Miranda]

vsViewer.exe - failed to open. Please set up the library search path in settings.

I've not seen this before.

[Selur]

Sounds like for some reason the Vapoursynth setup is messed up on your system,...
Did you install a global Vapoursynth or similar?

[Miranda]

I installed Hybrid_dev_2025.07.16-19404.exe

I removed the previous install using the uninstall option first.

[Selur]

That's the same version I use.
Does the Vapoursynth Preview fail on any source for you, or just for mp4s?