Possible 2 bugs in Linux & vapoursynth

[ALM]

Hi,

I use Hybrid and Vapoursynth, last versions, with Ubuntu (20.04 LTS), uptodate.
No real problem to compile Vapoursynth.
I'm trying to load a mkv with 3 video tracks and use MCTemporalDenoise on the first track, and
reencode it; others tracks are not interesting.

2 dual problems to load the file with Vapoursynth.

1. When I use "Prefer LWLibAVSource over FFMpegSource2", the generated .vpy load part is:

# Loading /global/leopard/cooking/back_Participant_10_Act_1_Trial_0.mkv using LWLibavSource
clip = core.lsmas.LWLibavSource(source="/global/leopard/cooking/back_Participant_10_Act_1_Trial_0.mkv", format="YUV422P8", stream_index=0, cache=0, prefer_hw=0)

prefer_hw seems coherent with Hybrid, it's the next graphic option : "Libab hardware decoding mode"
with default = 0

But IMHO, prefer_hw is an argument for LSMASHSource, not LWLibAVSource ?

The error is :
**************************************************************************************************
Python exception: LWLibavSource: Function does not take argument(s) named prefer_hw

Traceback (most recent call last):
  File "src/cython/vapoursynth.pyx", line 2231, in vapoursynth.vpy_evaluateScript
  File "src/cython/vapoursynth.pyx", line 2232, in vapoursynth.vpy_evaluateScript
  File "/global/leopard_nvme/encodingTempSynthSkript_23_58_00_8410.vpy", line 12, in <module>
    clip = core.lsmas.LWLibavSource(source="/global/leopard/cooking/back_Participant_10_Act_1_Trial_0.mkv", format="YUV422P8", stream_index=0, cache=0, prefer_hw=0)
  File "src/cython/vapoursynth.pyx", line 2042, in vapoursynth.Function.__call__
vapoursynth.Error: LWLibavSource: Function does not take argument(s) named prefer_hw
***************************************************************************************************

2. So, I'm trying to use FFMpegSource2 in place of LWLibAVSource. But my mkv has
3 video tracks. So the load part of the .vpy becomes :

# Loading source using FFMS2
clip = core.ffms2.Source(source="/global/leopard/cooking/back_Participant_10_Act_1_Trial_0.mkv",cachefile="/global/leopard_nvme/00_15_33_7110.ffindex",vtrack=0,format=vs.YUV422P8,alpha=False)

But IMHO, in core.ffms2.Source, the right name of the track is not "vtrack", but "track" ?

The error is :
**************************************************************************************************
Python exception: Source: Function does not take argument(s) named vtrack

Traceback (most recent call last):
  File "src/cython/vapoursynth.pyx", line 2231, in vapoursynth.vpy_evaluateScript
  File "src/cython/vapoursynth.pyx", line 2232, in vapoursynth.vpy_evaluateScript
  File "/global/leopard_nvme/encodingTempSynthSkript_00_15_33_7110.vpy", line 12, in <module>
    clip = core.ffms2.Source(source="/global/leopard/cooking/back_Participant_10_Act_1_Trial_0.mkv",cachefile="/global/leopard_nvme/00_15_33_7110.ffindex",vtrack=0,format=vs.YUV422P8,alpha=False)
  File "src/cython/vapoursynth.pyx", line 2042, in vapoursynth.Function.__call__
vapoursynth.Error: Source: Function does not take argument(s) named vtrack
**************************************************************************************************

WorkAround: do the job in 2 times.
First, extract the first video track in an tempo mkv without vapoursynth;
Second, use FFMpegSource2 with this new mkv with only one video track;
the argument vtrack is not used. Result is OK.

Thanks for your work & all the best,

Alain
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