Re: [FFmpeg-devel] [FFmpeg-cvslog] fftools/ffmpeg: rework setting sub2video parameters

From: Michael Niedermayer <michael@niedermayer.cc>
To: ffmpeg-devel@ffmpeg.org
Subject: Re: [FFmpeg-devel] [FFmpeg-cvslog] fftools/ffmpeg: rework setting sub2video parameters
Date: Wed, 7 Jun 2023 21:17:06 +0200
Message-ID: <20230607191706.GE870501@pb2> (raw)
In-Reply-To: <20230531142612.443E941082C@natalya.videolan.org>

[-- Attachment #1.1: Type: text/plain, Size: 1727 bytes --]

On Wed, May 31, 2023 at 02:26:11PM +0000, Anton Khirnov wrote:
> ffmpeg | branch: master | Anton Khirnov <anton@khirnov.net> | Tue May 23 22:54:23 2023 +0200| [20cacfe4936a8d5b643421b5ca93bb098f6b76dd] | committer: Anton Khirnov
> 
> fftools/ffmpeg: rework setting sub2video parameters
> 
> Set them in ifilter_parameters_from_dec(), similarly to audio/video
> streams. This reduces the extent to which sub2video filters need to be
> treated specially.
> 
> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=20cacfe4936a8d5b643421b5ca93bb098f6b76dd
> ---
> 
>  fftools/ffmpeg.c        |  6 ++---
>  fftools/ffmpeg_demux.c  | 21 ++++++++++++++++++
>  fftools/ffmpeg_filter.c | 58 +++++++++++++++----------------------------------
>  3 files changed, 41 insertions(+), 44 deletions(-)

This breaks subtitle location and size

./ffmpeg -i ~/tickets/4752/dump_dvbsubtitles.mp4 -y  -ss 5 -t 1 -filter_complex '[0:v][0:s]overlay' /tmp/file4752.ts && ffplay /tmp/file4752.ts

https://samples.ffmpeg.org/ffmpeg-bugs/trac/ticket4752/dump_dvbsubtitles.mp4

Before this commit the subtitles are centered at the bottom of the screen
after this patch the subtitles are tiny in the left middle of the screen

In the following case the subtitles disappear completely:

./ffmpeg -i ~/tickets/679/subtitles.ts -filter_complex '[0:v][0:s:0]overlay[vid]' -map  '[vid]' -bitexact  -t 3 file-4744-3.avi

https://samples.ffmpeg.org/ffmpeg-bugs/trac/ticket4744/subtitles.ts

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Dictatorship naturally arises out of democracy, and the most aggravated
form of tyranny and slavery out of the most extreme liberty. -- Plato

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 195 bytes --]

[-- Attachment #2: Type: text/plain, Size: 251 bytes --]

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".