[FFmpeg-devel] [PATCH] avfilter/vf_subtitles: pass storage size to libass

[Soft Works]

> -----Original Message-----
> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of Oneric
> Sent: Monday, March 14, 2022 8:50 PM
> To: FFmpeg development discussions and patches <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH] avfilter/vf_subtitles: pass storage
> size to libass
> 
> On Mon, Mar 14, 2022 at 19:35:36 +0000, Soft Works wrote:
> >
> > I've been at the same point some time ago where I wondered why ffmpeg is
> > not setting this, but then I had found that it is overridden by the call
> > to ass_set_pixel_aspect().
> >
> > ass_set_pixel_aspect() is setting settings.par and if I'm not mistaken,
> > an existing par setting leads to the storage size setting to be ignored:
> 
> It’s not overridden. Only the explicit PAR is currently preferd over the
> implicit derivation from storage and frame size. However as I stated in
> the patch description and the comment:
>   “some tags depend on the exact storage resolution of the video”
>   “it actually goes farther than just the aspect ratio”
> 

I found only one other place where storage_h is used (for determining 
blur size) but I didn't find any other usage in the libass source code.
That's what I'm wondering about.

Thanks,
sw