[FFmpeg-devel] [PATCH] ffmpeg: Set duration on encoded subtitle packets.

Philip Langdale philipl at overt.org
Sun Jun 3 23:20:07 CEST 2012

On Sun, 3 Jun 2012 21:08:40 +0200
Clément Bœsch <ubitux at gmail.com> wrote:

> MicroDVD demuxer is making use of that duration field; are you sure it
> doesn't break anything to override it?
> (Common scenario: ffmpeg -i microdvd.sub out.ass, see 2d52ee8a for
> more information)

Your example is on the decoder side. I'm talking about the encoder.
Today, 'ffmpeg' will always pass subtitle packets to the muxer with
no duration - and we have got away with this because the muxers don't
require packet duration for the formats we support (eg: the muxer
parses srt and ass packets to get the duration). For timed text, there's
no side-band way to pass duration, so we have to do it properly on
the packet.


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