FreezeFrame
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AviSynth+
Up-to-date documentation: https://avisynthplus.readthedocs.io
FreezeFrame(clip clip, int first-frame, int last-frame, int source-frame)
The FreezeFrame filter replaces all the frames between first-frame and last-frame with a copy of source-frame. The sound track is not modified. This is useful for covering up glitches in a video in cases where you have a similar glitch-free frame available.