If it isn't then something is wrong with the Vapoursynth installation. Open VLC, navigate to Tools -> Preferences, click on Show settings - All, scroll down to the Video -> Filters and ensure that 'Vapoursynth' filter is listed here.

Ensure that the video filter is correctly installed in VLC:.If you see VLC: unsupported input video format message in SVP's log - try to turn off Hardware acceleration in VLC -> Preferences -> Inputs/Codecs.Ensure that SVP's control interface is turned on under Tools -> Preferences, Show settings -> All, Interface -> Control interfaces.Run SVP -> Utilities -> SVP in VLC to install SVP's plugins for VLC.Locate the plugins path, for example: /usr/lib/vlc/plugins, write it to the property in SVP's All settings.macOS Ventura of later: may ask you for an additional permissions for app modifications.Choose Utilities -> SVP in VLC from SVP's main menu.you must download a 'macOS (Apple Silicon)' version on M1/M2 Macs. Install the correct version of VLC - i.e.Run VLC, open Tools -> Preferences, click Show settings -> All, navigate to Interface -> Control interfaces and turn on SVP control interface.

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