[FFmpeg-user] Multiline subtitles without thin dark line

[Steinar Apalnes]

>
> > On 15 Feb 2023, at 13:21, Steinar Apalnes <steipal at gmail.com> wrote:
> >
> > Hi,
> >
> > I want to create subtitles with multiple text lines using BorderStyle=3
> in
> > order to have the background color adapt to the length of each line. The
> > problem is that I get a thin dark line between every text line.
>
> You do not have a stupid black line, you have overlapping boxes so the
> alpha will double.
> Increase line spacing and it ’should’ be fine. (I did not try, but I’m
> pretty confident.)
> And for my taste, just outline is enough, boxes are ugly and came from
> stupid CC / TeleText.
>
> Bouke
>

I know it's due to overlapping boxes. I cannot find anything in the ASS
specs. or the subtitles filter to alter the line spacing. I would be very
happy if your confidence could point me to the right setting ;-)
Anyway, overlapping boxes is (to my knowledge) handled by the filter so in
my opinion it should be addressed there. Cause I don't believe anyone
needing this style wants the result created by these overlapping
transparent boxes. Like this dude:
https://stackoverflow.com/questions/72093116/ffmpeg-subtitles-background-issue-when-multiple-lines-using-srt-format
Of course suggesting another style is not a solution.

-steinar