[poisondeathray]

Yes , I can replicate the avisynth MT issue in this post , despite trying some manipulations like mod16 (1280x720 instead of 1288x720), tried reducing prefetch value etc.. . Crashes very quickly . Always.
https://forum.doom9.org/showthread.p...95#post1813995

It's stable in vpy with dct=1, 100% CPU usage . I only tested for a few minutes, but the crash in avs occurred everytime in seconds or less.

But I used an image instead of colorbarshd() source (I don't see equivalent in vapoursynth), and removegrain mode=22 might be different. In the vpy documentation mode=22 is reported as "to do" , but I doubt those would make a big difference
http://www.vapoursynth.com/doc/plugins/rgvs.html

import vapoursynth as vs
core = vs.get_core()
clip = core.lsmas.LWLibavSource(r'F:\image720.png')
clip = clip * 100000
clip = core.std.AssumeFPS(clip, fpsnum=30, fpsden=1)
clip = core.resize.Bicubic(clip, format=vs.YUV420P8, matrix_s="709")

prefiltered = core.rgvs.RemoveGrain(clip, mode=22)
super = core.mv.Super(clip, hpad = 16, vpad = 16, levels = 1)
superfilt = core.mv.Super(prefiltered, hpad = 16, vpad = 16)
backward = core.mv.Analyse(superfilt, isb = True, blksize = 8, overlap = 4, search = 3, dct = 1)
forward = core.mv.Analyse(superfilt, isb = False, blksize = 8, overlap = 4, search = 3, dct = 1)
forward_re = core.mv.Recalculate(super, forward, blksize = 4, overlap = 2, thsad = 100)
backward_re = core.mv.Recalculate(super, backward, blksize = 4, overlap = 2, thsad = 100)
clip = core.mv.FlowFPS(clip, super, backward_re, forward_re, num = 60, den = 1, blend = False, ml = 200, mask = 2)

#	prefiltered = RemoveGrain(source, 22)
#	super = MSuper(source, hpad = 16, vpad = 16, levels = 1)
#	superfilt = MSuper(prefiltered, hpad = 16, vpad = 16) # all levels for MAnalyse
#	backward = MAnalyse(superfilt, isb = true, blksize = 8, overlap = 4, search = 3, dct = 1)
#	forward = MAnalyse(superfilt, isb = false, blksize = 8, overlap = 4, search = 3, dct = 1)
#	forward_re = MRecalculate(super, forward, blksize = 4, overlap = 2, thSAD = 100)
#	backward_re = MRecalculate(super, backward, blksize = 4, overlap = 2, thSAD = 100)
#	out = MFlowFps(source, super, backward_re, forward_re, num = fps_num, den = fps_den, blend = false, ml = 200, mask = 2)
clip.set_output()