[HELP] My problems with Hybrid

[dsiomnainc]

Hello! 

've been using version 2025.07.11.1 for a long time because newer versions don't work very well for me.
Now that I have the time and desire to figure out what the problem is, I'd be happy if you could help me.

I install last Dev version.

So far, I see two main issues:

1. On newer versions, if I select the "Windows" or "Windows Vista" styles, the drop-down lists become transparent, making them difficult to use.
This issue doesn't exist on the older version running on the same system.





2. VSViewer isn't working due to LSMASHSource.dll version 1266; it works fine with version 1252.
I hoped the problem would resolve itself over time, but it hasn't resolved itself after six months.
During that time, I reinstalled the operating system (Windows 11), but unfortunately, the problem persists, and I can't figure out where to look.

[Selur]

I hoped the problem would resolve itself over time, but it hasn't resolved itself after six months.

Not reporting an issue and hoping it resolves itself,...
For the future read https://forum.selur.net/thread-3.html and provide proper details.

1. On newer versions, if I select the "Windows" or "Windows Vista" styles, the drop-down lists become transparent, making them difficult to use.

Yes, that is a known issue in Qt 6. I wrote a workaround for it, hope it will help.

2. VSViewer isn't working due to LSMASHSource.dll version 1266; it works fine with version 1252.

Tried a few sources which all work fine with core.lsmas.LWLibavSource.
Can't reproduce this.


=> uploaded a new dev, which should fix the transparency issue of the combo box.



Cu Selur

[dsiomnainc]

1. On newer versions, if I select the "Windows" or "Windows Vista" styles, the drop-down lists become transparent, making them difficult to use.

Yes, that is a known issue in Qt 6. I wrote a workaround for it, hope it will help.

Thank you, this problem has been fixed.

I hoped the problem would resolve itself over time, but it hasn't resolved itself after six months.

Not reporting an issue and hoping it resolves itself,... 
For the future read https://forum.selur.net/thread-3.html and provide proper details.

I reported that issue, but we couldn't find a solution. 
Unfortunately, I didn't have the time to figure it out, so I decided to stick with the old version. 
By "it will resolve itself," I meant I thought the problem might be with the library itself, and perhaps a new version of the library, not the hybrid, would be released and change that.

2025.12.11 - 00:57:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: VapoursynthScriptView::update - Ignored script changes; while adjusting to input
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: generating vapoursynth script for preview,..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: generateScript - dual: 0, crop: 0, preview: 1, script: 0, job: 0
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: generateScript - dual: 0, crop: 0, preview: 1, script: 0, job: 0
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no timecode in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Profile in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: target bit depth from filtering model: 8
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: getColorSampling for 4:4:4 YUV at 10bit
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  -> input&current colorSampling: YUV444P10
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Luminance scale: tv -> yuvPCScale: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Codec in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: getColorSampling for i420 i420 at 8bit
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  -> input&current colorSampling: YUV420P8
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: target color: YUV420P8
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: generateScript,..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   CPU: AMD Ryzen 9 9950X 16-Core Processor           
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   noAVX2: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   nvidiaAvailable: true
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Color Transfer in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Color Primes in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no typ in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  vc1: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Disabling DGDevNV incompatible format: FFV1, color: YUV444P10
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: dgDecNVCompatible: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: vsDGDecNVAvailable: true
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: vsUseDGDecNV: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Disabling DGDec incompatible input container!
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Vapoursynth tryLSMASHSource for: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   vsPreferLSMASH: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   mp4Compatible: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   forcing CFR output: false
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: -> using LibAvSource
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Color Transfer in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Color Primes in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   getStartAndEnd(cutStartTime: 0, cutEndTime: 1740.87, selectionStartTime: 0, selectionEndTime: 1740.87, ...)
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   startTime: 0.00000000
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   endTime: 1740.87400000
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   -> startTime: 0, endTime: 1740.87
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   matchesChapter: true
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: no deinterlacing needed (progressive video),..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no timecode in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: using script:
# Imports
import vapoursynth as vs
# getting Vapoursynth core
import sys
import os
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/SourceFilter/LSmashSource/LSMASHSource.dll")
# Import scripts
import validate
# Source: 'C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv'
# Current color space: YUV444P10, bit depth: 10, resolution: 720x480, frame rate: 29.97fps, scanorder: progressive, yuv luminance scale: limited, matrix: 470bg, format: FFV1
# Loading 'C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkvÄ using LWLibavSource
clip = core.lsmas.LWLibavSource(source="C:/Users/DSIOMNAINC/Desktop/Alita/1/01_VDub.mkv", format="YUV444P10", stream_index=0, cache=0, prefer_hw=0)
frame = clip.get_frame(0)
# setting color matrix to 470bg.
clip = core.std.SetFrameProps(clip, _Matrix=vs.MATRIX_BT470_BG)
# setting color transfer (vs.TRANSFER_BT601), if it is not set.
if validate.transferIsInvalid(clip):
  clip = core.std.SetFrameProps(clip=clip, _Transfer=vs.TRANSFER_BT601)
# setting color primaries info (to vs.PRIMARIES_BT470_BG), if it is not set.
if validate.primariesIsInvalid(clip):
  clip = core.std.SetFrameProps(clip=clip, _Primaries=vs.PRIMARIES_BT470_BG)
# setting color range to TV (limited) range.
clip = core.std.SetFrameProps(clip=clip, _ColorRange=vs.RANGE_LIMITED)
# making sure frame rate is set to 29.97fps
clip = core.std.AssumeFPS(clip=clip, fpsnum=30000, fpsden=1001)
# making sure the detected scan type is set (detected: progressive)
clip = core.std.SetFrameProps(clip=clip, _FieldBased=vs.FIELD_PROGRESSIVE) # scan type: progressive
# adjusting output color from YUV444P10 to YUV420P8 for x264Model
clip = core.resize.Bicubic(clip=clip, dither_type="error_diffusion", format=vs.YUV420P8, range_in_s="limited")
# set output frame rate to 29.97fps (progressive)
clip = core.std.AssumeFPS(clip=clip, fpsnum=30000, fpsden=1001)
# output
clip.set_output()
# script was created by Hybrid 2025.12.10.1
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   writing: UTF8BOM
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  VapoursynthPreview enabling show,..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: VapoursynthPreview m_currentTempVPY: C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewVapoursynthFile00_58_13_234.vpy
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: VapoursynthPreview m_currentCall: C:\Program Files\Hybrid\64bit\Vapoursynth\vsViewer.exe --preview-only C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewVapoursynthFile00_58_13_234.vpy --matrix Rec601 -style=windowsvista
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Creating index files,...
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Files to index for VAPOURSYNTHPREVIEW:
 
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Indexer createIndexFiles disable GUI(1),..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: enableGui 0 + -1 = -1
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  -> m_toIndex is empty,... -> nothing to do,...
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: VsScriptGenerator indexerFinished(4612,0): VAPOURSYNTHPREVIEW
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: VsScriptGenerator indexerFinished enable GUI(5),..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: enableGui -1 + 1 = 0
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  indexing finished,..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: startPreview,..C:\Program Files\Hybrid\64bit\Vapoursynth\vsViewer.exe --preview-only C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewVapoursynthFile00_58_13_234.vpy --matrix Rec601 -style=windowsvista
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  VapoursynthPreview disable show(2),..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  VapoursynthPreview disable updating(2),..
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected vsViewer -> 2finished(int, QProcess::ExitStatus) to VapoursynthPreview -> 1playerFinished(int, QProcess::ExitStatus), type: 384
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected vsViewer -> 2readyReadStandardOutput() to VapoursynthPreview -> 1handlePreviewOutput(), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected vsViewer -> 2readyReadStandardError() to VapoursynthPreview -> 1handlePreviewOutput(), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: startPreview call: C:\Program Files\Hybrid\64bit\Vapoursynth\vsViewer.exe --preview-only C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewVapoursynthFile00_58_13_234.vpy --matrix Rec601 -style=windowsvista --listen 17908_VPY_ --listen-to HYBRID
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: adjustProcessEnvironmentOfProcess(vsViewer),...
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: adjusted ProcessEnvironmentOfProcess(vsViewer),...
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2messageReceived(QString) to VapoursynthPreview -> 1gotMessage(QString), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2connected() to unnamed -> 1socket_connected(), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2disconnected() to unnamed -> 1socket_disconnected(), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2readyRead() to unnamed -> 1socket_readReady(), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2errorOccurred(QLocalSocket::LocalSocketError) to unnamed -> 1socket_error(QLocalSocket::LocalSocketError), type: 128
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: tokenizing(2) 'C:\Program Files\Hybrid\64bit\Vapoursynth\vsViewer.exe' with:
  --preview-only
  C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewVapoursynthFile00_58_13_234.vpy
  --matrix
  Rec601
  -style=windowsvista
  --listen
  17908_VPY_
  --listen-to
  HYBRID
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: tool(2): "C:\Program Files\Hybrid\64bit\Vapoursynth\vsViewer.exe"
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: arguments(2):
  --preview-only
  C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewVapoursynthFile00_58_13_234.vpy
  --matrix
  Rec601
  -style=windowsvista
  --listen
  17908_VPY_
  --listen-to
  HYBRID
2025.12.11 - 00:58:13_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Preview::indexingIsFinished 'VAPOURSYNTHPREVIEW' ignored,..
2025.12.11 - 00:58:34_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: got close event,..

[Selur]

Like I wrote: works fine here, but you can use BestSource as alternative

[dsiomnainc]

The "Hybrid\64bit\Avisynth\avisynthPlugins" folder currently contains LSMASHSource.dll version 1252.
If I replace it with a newer version (1266), avsViewer also stops running. 
Meanwhile, both VSViewer and avsViewer appear in the Task Manager, and the computer even starts buzzing, but the window itself doesn't appear.

2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: generating avisynth script for preview,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: setViews,...
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  scriptView: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  dualView: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  avisynthPreview: true
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  avsSplitFilterPreview: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  splitView: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  cropView: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no typ in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth generate script called,...
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no typ in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  input: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: input bit depth: 10
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Codec in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  video codec:
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  videoformat: FFV1
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: set targetColorSpace(2) to: RGB32
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Rotation in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  input rotation:
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  avisynthTargetColorSpace: RGB32
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  input colorSampling: 4:4:4
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  input colorSpace: YUV
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: setColorSampling for: 4:4:4 YUV
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  -> input&current colorSampling: YV24
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  id: mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  videoCount: 1
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  ffmpegVideoID: 0
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  forceDecoderCFR: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no Profile in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no interlacedAnalyseResult in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  interlacedAnalyseResult:
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: scanorder: NOT SET
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  m_progressiveInput: true
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  interlaced input: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  frameRateMode: CFR
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no timecode in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  m_inputNeedsAvisynth: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  frimCompatible: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  vc1: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: clearOldCacheFor: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: getCacheFileFor: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  title:
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needsDirectShow: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  deinterlacer: QTGMC (Avisynth)
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  noDeinterlace: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no typ in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: shortFileName for: C:\Program Files\Hybrid\64bit\Avisynth\avisynthPlugins\
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: -> shortened name: C:\Program Files\Hybrid\64bit\Avisynth\avisynthPlugins\
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: shortFileName for: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: -> shortened name: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   getStartAndEnd(cutStartTime: 0, cutEndTime: 1740.87, selectionStartTime: 0, selectionEndTime: 1740.87, ...)
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   startTime: 0.00000000
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   endTime: 1740.87400000
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   -> startTime: 0, endTime: 1740.87
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:   matchesChapter: true
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: -> nothing to do, no resizing
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: adjustColorMatrixValue(bt470, 0)
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  deinterlaceNeeded: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  subtitleNeeded: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  filterNeeded: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  avisynthPreview: true
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  aviSourceNeeded: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  neededForCustom: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth:
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needed for input: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needed for subtitle: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needed for deinterlacing: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needed for filtering: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needed for custom filtering: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  needed for image sequence: false
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Generated script: ClearAutoloadDirs()
SetFilterMTMode("DEFAULT_MT_MODE", MT_MULTI_INSTANCE)
LoadPlugin("C:\Program Files\Hybrid\64bit\Avisynth\avisynthPlugins\LSMASHSource.dll")
Import("C:\Program Files\Hybrid\64bit\Avisynth\avisynthPlugins\mtmodes.avsi")
# loading source: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
# color sampling YV24@10, matrix: bt470, scantyp: progressive, luminance scale: limited
LWLibavVideoSource("C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv",cache=false,format="YUV444P10", prefer_hw=0,repeat=true)
# current resolution: 720x480
# adjust color to RGB32 (color matrix: Rec601)
ConvertToRGB32(matrix="Rec601")
# setting output fps to 29.97000fps
AssumeFPS(30000,1001)
PreFetch(16)
#  output: color sampling RGB32@10, matrix: bt470, scantyp: progressive, luminance scale: limited
return last
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: There's no timecode in mkv_9d97fe3fc2ce11c30b5e9f64736a5223_853323747
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: checkSubtitleStyles
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: -> no subtitles -> no styles ;)
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: With 'C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs'
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  enabling show,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: AvisynthPreview m_currentTempAVS: C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: using script: ClearAutoloadDirs()
SetFilterMTMode("DEFAULT_MT_MODE", MT_MULTI_INSTANCE)
LoadPlugin("C:\Program Files\Hybrid\64bit\Avisynth\avisynthPlugins\LSMASHSource.dll")
Import("C:\Program Files\Hybrid\64bit\Avisynth\avisynthPlugins\mtmodes.avsi")
# loading source: C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv
# color sampling YV24@10, matrix: bt470, scantyp: progressive, luminance scale: limited
LWLibavVideoSource("C:\Users\DSIOMNAINC\Desktop\Alita\1\01_VDub.mkv",cache=false,format="YUV444P10", prefer_hw=0,repeat=true)
# current resolution: 720x480
# adjust color to RGB32 (color matrix: Rec601)
ConvertToRGB32(matrix="Rec601")
# setting output fps to 29.97000fps
AssumeFPS(30000,1001)
PreFetch(16)
#  output: color sampling RGB32@10, matrix: bt470, scantyp: progressive, luminance scale: limited
return last
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: using 64bit-avsViewer for Preview
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: AvisynthPreview m_currentCall: "C:\Program Files\Hybrid\64bit\Avisynth\avsViewer64.exe" --input "C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs" --aspect 1 --matrix Rec601
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: createIndexFiles with AvisynthFileGenerator
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Creating index files,...
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Files to index for AVISYNTHPREVIEW:
 
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Indexer createIndexFiles disable GUI(1),..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: enableGui 0 + -1 = -1
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  -> m_toIndex is empty,... -> nothing to do,...
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: 'AvisynthFileGenerator' indexing finished (exitcode: 4612)
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: enableGui -1 + 1 = 0
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: HybridMainWindow::indexingIsFinished 'AVISYNTHPREVIEW' ignored,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Preview::indexingIsFinished 'AVISYNTHPREVIEW' ignored,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  AvisyntPreview, indexing finished,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: startPreview,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected avsViewer -> 2finished(int, QProcess::ExitStatus) to AvisynthPreview -> 1playerFinished(int, QProcess::ExitStatus), type: 384
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected avsViewer -> 2readyReadStandardOutput() to AvisynthPreview -> 1handlePreviewOutput(), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected avsViewer -> 2readyReadStandardError() to AvisynthPreview -> 1handlePreviewOutput(), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2messageReceived(QString) to AvisynthPreview -> 1gotMessage(QString), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2connected() to unnamed -> 1socket_connected(), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2disconnected() to unnamed -> 1socket_disconnected(), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2readyRead() to unnamed -> 1socket_readReady(), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Connected unnamed -> 2errorOccurred(QLocalSocket::LocalSocketError) to unnamed -> 1socket_error(QLocalSocket::LocalSocketError), type: 128
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: using 64bit-avsViewer for Preview
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: using 64bit AvisynthViewer: C:\Program Files\Hybrid\64bit\Avisynth\avsViewer64.exe
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: adjustProcessEnvironmentOfProcess(avsViewer64),...
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: adjusted ProcessEnvironmentOfProcess(avsViewer64),...
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: startPreview call: "C:\Program Files\Hybrid\64bit\Avisynth\avsViewer64.exe" --input "C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs" --aspect 1 --matrix Rec601 --listen 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: tokenizeAndStart(1): "C:\Program Files\Hybrid\64bit\Avisynth\avsViewer64.exe" --input "C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs" --aspect 1 --matrix Rec601 --listen 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  tool(1): C:\Program Files\Hybrid\64bit\Avisynth\avsViewer64.exe
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  tool: C:\Program Files\Hybrid\64bit\Avisynth\avsViewer64.exe
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  argumentString(1): --input "C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs" --aspect 1 --matrix Rec601 --listen 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9:  arguments(1):
  --input
  C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs
  --aspect
  1
  --matrix
  Rec601
  --listen
  13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - START ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: aspect mult: 1
matrix: Rec601
server id: 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - END ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: aspect mult: 1
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: matrix: Rec601
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: server id: 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - START ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: -> using desktop resolution: 1920x1080
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - END ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: -> using desktop resolution: 1920x1080
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - START ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: AvsViewer started ipcClient&Server with id 13960
[avsViewer Client]: setting message AvsViewer started ipcClient&Server with id 13960
[avsViewer Client]: sending message AvsViewer started ipcClient&Server with id 13960
[avsViewer Client]: connected, nothing to send,..
Initializing the avisynth script environment,..
[avsViewer Client]: setting message Initializing the avisynth script environment,..
[avsViewer Client]: sending message Initializing the avisynth script environment,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - END ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: AvsViewer started ipcClient&Server with id 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: [avsViewer Client]: setting message AvsViewer started ipcClient&Server with id 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: [avsViewer Client]: sending message AvsViewer started ipcClient&Server with id 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: [avsViewer Client]: connected, nothing to send,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: Initializing the avisynth script environment,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: [avsViewer Client]: setting message Initializing the avisynth script environment,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: [avsViewer Client]: sending message Initializing the avisynth script environment,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: AvisynthPreview got IPC-message: AvsViewer started ipcClient&Server with id 13960
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: AvisynthPreview got IPC-message: Initializing the avisynth script environment,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - START ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: loaded avisynth dll,..(C:/Program Files/Hybrid/64bit/Avisynth/AviSynth.dll)
loaded CreateScriptEnvironment definition from dll,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - END ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: loaded avisynth dll,..(C:/Program Files/Hybrid/64bit/Avisynth/AviSynth.dll)
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: loaded CreateScriptEnvironment definition from dll,..
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - START ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Created script env (current): 11
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - END ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: Created script env (current): 11
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - START ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Importing C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: --- avsViewer output - END ---
2025.12.11 - 01:31:59_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: Avisynth preview output: Importing C:\Users\DSIOMNAINC\AppData\Local\Temp\tempPreviewAvisynthFile01_31_59_571.avs
2025.12.11 - 01:32:08_Windows 11 Version 25H2 (64bit)_2025.12.10.1 - level 9: got close event,..

[dsiomnainc]

I checked it on another PC with Windows 10, there are no problems there, I'll think about it...

In avspmod, the old library also works, but the new one doesn't...very strange...

---

I finally figured it out.
The new version works on my computer, but the problem was with the source file.
I try to use the FFV1 format. The old version of the library opens the file in 1-2 seconds.
The new library takes about a minute or two to open a 30-second file.
The problem is that my file is 30 minutes long, not 30 seconds. At the same time, the old version opens a 30-minute file in 1-2 seconds.
It might have opened if I had waited about an hour or two, but I didn't wait that long.

Perhaps I shouldn't use FFV1 (For example, ProRes opens quickly.), or maybe I should use the old library instead, as it's faster.

Example file:
https://cloud.mail.ru/public/jB2e/DFZ9nJ7gs

[Selur]

Perhaps I shouldn't use FFV1 (For example, ProRes opens quickly.), or maybe I should use the old library instead, as it's faster.

... or report the issue to the LSMASHSource folks, or use BestSource ...
I can confirm, that with your FFV1 file, I can reproduce the problem with LWLibavSource.

Issue seems to be that mkvtoolnix uses V_MS/VFW/FOURCC here, I first thought it might be a vfw wrapper problem

Codec ID                                 : V_MS/VFW/FOURCC / FFV1

using ffmpeg instead of mkvmerge for the muxing, one gets:

Format                                   : FFV1

but the indexing is still slow.

Cu Selur