[BUG] SVT-AV1 + Vapoursynth encode error

[andrewschen]

Tested on Hybrid_dev_2026.08.19-185814 and Hybrid_dev_2026.08.13:

Choose svt-av1 as encoder, load a input file, don't enable any filter in vapoursynth, set an output file, add to queue, start the job, no error happens.

Choose svt-av1 as encoder, load a input file, enable at least one filter in vapoursynth, set an output file, add to queue, start the job, an error like "2026-08-20@22_24_43_7310_03_video crashed: Error: Invalid parameter '--input' with value '\\.\pipe\2026-08-20@22_24_43_7310_03_video' will happen.


One more thing: In Hybrid_dev_2026.08.19-18581, if I enable KNLMeansCL and YUV420 chroma location in Vapoursynth -> Misc -> Script, the script looks like this:

clip = core.resize.Bicubic(clip=clip, format=vs.RGB24, matrix_in_s="709"chromaloc=0, range_in_s="limited", range_s="full")

maybe missing comma?

In Hybrid_dev_20260625-152245 it is:

clip = core.resize.Bicubic(clip=clip, format=vs.RGB24, matrix_in_s="709", range_in_s="limited", chromaloc=0)

[Selur]

Strange, I'm pretty sure I explicitly have code to not use named pipes with SVTAV1 and SVTHEVC.
Will also look at the chromaloc thing.

[Selur]

Uploaded a new dev version.
Let me know whether that fixes the issue for you.

Cu Selur

[andrewschen]

Yes it fixes the issues.


There's another thing: The "yuv420 chroma location" setting in vapoursynth, sometimes it isn't applied correctly?

for example:

source yuv420p8
yuv420 chroma location left in VS
Filters: SMDegrain (Gimmick YUV444P16) -> KNLMeansCL(plane RGB)
output yuv420p10

result:

# Adjusting color sampling to YUV444P16 for vsSMDegrainGimmick clip = core.resize.Bicubic(clip=clip, format=vs.YUV444P16, chromaloc=0) # removing grain using SMDegrain clip = smdegrain.SMDegrain(clip, tr=1, interlaced=False) # adjusting color space from YUV444P16 to RGB48 for vsKNLMeansCL clip = core.resize.Bicubic(clip=clip, format=vs.RGB48, matrix_in_s="709", range_in_s="limited", range_s="full") # denoising using KNLMeansCL clip = core.knlm.KNLMeansCL(clip, channels="RGB", device_id=0) # adjusting output color from RGB48 to YUV420P10 for SvtAv1Model clip = core.resize.Bicubic(clip=clip, format=vs.YUV420P10, matrix_s="709", range_in_s="full", range_s="limited", dither_type="error_diffusion")

I think chromaloc=0 should be in the last line?

[Selur]

Hmm,.. I'll look at it.

[Selur]

Okay, took me a while to see the problem (I missed that I did add the chroma location, as an argument to a string builder, but miscounted the placements and thus it was not added).

Uploaded a new dev, now like the description says "chromaloc" should be added in both directions of the conversion.


Cu Selur

[andrewschen]

Yes, fixed in the newest dev.