ASS subtitles rendering issue at 4K

[Max D.]

Hi guys,

I'm having an issue with Advanced SubStation Alpha subtitles displayed over 4K videos in VLC. They have visual artefacts, as in this image:



There's a one-pixel white "outline" around the actual outline. The issue is not present at lower resolutions or at any resolutions on MPC-HC. From brief research, I found that the issue might be rooted in libass's subtitle rendering issue at 4K (arbitrary bitmap limit). The good news is, the latest version of libass (0.13.7) has this issue fixed.

So my question is, does VLC use the latest libass release? If not, could you please add it? If yes, what do you think could be the underlying issue?

This is important to me, so any help is appreciated. Thanks.

[Jean-Baptiste Kempf]

Yes, I will update the libass release for next VLC 3.0 release.

[Max D.]

Thanks a lot!