"bad sequence header magic." usally means there is a problem with the Avisynth or Vapoursynth script.
Looking at the Vapoursynth script in the debug output:
# Imports
import os
import sys
import ctypes
# Loading Support Files
Dllref = ctypes.windll.LoadLibrary("C:/Program Files/Hybrid/64bit/vsfilters/Support/libfftw3f-3.dll")
import vapoursynth as vs
# getting Vapoursynth core
core = vs.core
# Import scripts folder
scriptPath = 'C:/Program Files/Hybrid/64bit/vsscripts'
sys.path.insert(0, os.path.abspath(scriptPath))
# Loading Plugins
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/MiscFilter/MiscFilters/MiscFilters.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/SharpenFilter/AWarpSharp2/libawarpsharp2.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/DebandFilter/Flash3kDeband/flash3kyuu_deband.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/DenoiseFilter/CTMF/CTMF.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/GrainFilter/RemoveGrain/RemoveGrainVS.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/DenoiseFilter/HQDN3D/libhqdn3d.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/DenoiseFilter/NEO_FFT3DFilter/neo-fft3d.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/Support/libmvtools.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/DerainbowFilter/BiFrost/libbifrost.dll")
core.std.LoadPlugin(path="C:/Program Files/Hybrid/64bit/vsfilters/SourceFilter/LSmashSource/vslsmashsource.dll")
# Import scripts
import mvsfunc
import havsfunc
# source: 'E:\HB\Animaniacs.S01e20.Dvd.Remux-1.mkv'
# current color space: YUV420P8, bit depth: 8, resolution: 712x480, fps: 29.97, color matrix: 470bg, yuv luminance scale: limited, scanorder: progressive
# Loading E:\HB\Animaniacs.S01e20.Dvd.Remux-1.mkv using LWLibavSource
clip = core.lsmas.LWLibavSource(source="E:/HB/Animaniacs.S01e20.Dvd.Remux-1.mkv", format="YUV420P8", cache=0, fpsnum=30000, fpsden=1001, prefer_hw=0)
# making sure input color matrix is set as 470bg
clip = core.resize.Bicubic(clip, matrix_in_s="470bg",range_s="limited")
# making sure frame rate is set to 29.970
clip = core.std.AssumeFPS(clip=clip, fpsnum=30000, fpsden=1001)
# Setting color range to TV (limited) range.
clip = core.std.SetFrameProp(clip=clip, prop="_ColorRange", intval=1)
# rainbow removal using BiFrost
clip = core.bifrost.Bifrost(clip=clip, interlaced=False)
# removing grain using TemporalDegrain
clip = havsfunc.TemporalDegrain(inpClip=clip)
# denoising using Neo-FFT3D
clip = core.neo_fft3d.FFT3D(clip=clip, sigma=8.00, sigma2=2.00, sigma3=2.00, sigma4=2.00)
# debanding using f3kdb
clip = core.f3kdb.Deband(clip, keep_tv_range=True, output_depth=8)
# sharpening using AWarpSharp2
clip = core.warp.AWarpSharp2(clip=clip, blur=2)
clip = havsfunc.EdgeCleaner(c=clip)
# deringing using HQDeringmod
clip = havsfunc.HQDeringmod(clip, nrmode=2, darkthr=3.0)
# set output frame rate to 29.970fps
clip = core.std.AssumeFPS(clip=clip, fpsnum=30000, fpsden=1001)
# Output
clip.set_output()
I don't see anything wrong with it.
-> Try whether Vapoursynth Preview porperly shows a preview or whether it reports an error message.
Cu Selur
Ps.: If you installed the latest version over an existing install which was 2021.07.18.1 or older, make sure to deinstall the previous installation, otherwise Vapoursynth will fail.
PPs.: The video download link doesn't work, asks for a username and password.
