[BUG] Image sequence not working in new version

[Selur]

Looking at the Vapoursynth script used:

# Imports
import vapoursynth as vs
core = vs.get_core()
# source: 'D:/Edicion/098/000000.jpg'
# current color space: YUV420P8, bit depth: 8, resolution: 1440x1080, fps: 29.97, color matrix: 709, yuv luminance scale: full, scanorder: progressive
# Loading D:\Edicion\%01d98\000000.jpg using vsImageReader
clip = core.imwri.Read("D:/Edicion/%01d98/000000.jpg", firstnum=0)
clip = core.std.Trim(clip=clip, length=38841)
# Input color space is assumed to be RGB24
# making sure frame rate is set to 29.97
clip = core.std.AssumeFPS(clip=clip, fpsnum=30000, fpsden=1001)
# Setting color range to PC (full) range.
clip = core.std.SetFrameProp(clip=clip, prop="_ColorRange", intval=0)
# adjusting output color from: RGB24 to YUV420P8 for x264Model (i420@8)
clip = core.resize.Bicubic(clip=clip, format=vs.YUV420P8, matrix_s="709", range_s="full")
# set output frame rate to 29.970fps
clip = core.std.AssumeFPS(clip=clip, fpsnum=30000, fpsden=1001)
# Output
clip.set_output()

I see no direct problem with the script. Aside from that folder name, which might cause problems with "ImageMagick Writer-Reader" source filter.
-> So my first advice would be to try whether chaning the folder name helps.

Looking at the encoding call:

"C:\Program Files\Hybrid\64bit\Vapoursynth\vspipe.exe" "D:\Temp\encodingTempSynthSkript_2021-02-02@10_40_08_0910.vpy" - --y4m | "C:\Program Files\Hybrid\64bit\x264.exe" --preset slower --crf 16.00 --profile high --level 4.0 --ref 5 --bframes 5 --sync-lookahead 12 --qpmax 51 --psy-rd 0.40:0.00 --aq-mode 3 --vbv-maxrate 25000 --vbv-bufsize 31250 --sar 1:1 --deblock 1:1 --demuxer y4m --input-csp yuvj420p --input-range pc --fps 30000/1001 --output-depth 8 --output "D:\Temp\2021-02-02@10_40_08_0910_02.264" -

everything looks fine too.

The error:

x264 output: y4m [error]: bad sequence header magic

usually means that something went wrong with the processing of the Vapoursynth script.
-> Does the Vapoursynth Preview work properly or does it show an error message?

Cu Selur