[FFmpeg-devel] Question regarding FLV Metadata patch dated 10 Sep, 2010

[Pranav Desai]

On Wed, Oct 5, 2011 at 6:24 PM, Michael Niedermayer <michaelni at gmx.at>wrote:

> On Wed, Oct 05, 2011 at 11:11:18AM -0700, Pranav Desai wrote:
> > Hello,
> >
> > I have a question regarding a patch that adds metadata to flv output.
> >
> > Here is the link to the patch
> >
> http://git.videolan.org/?p=ffmpeg.git;a=commit;h=16f825085a53dc7241ef375e9bed9856435d4c16
> >
> > Actually I ran into an issue when transcoding Youtube videos. The input
> > video has size 608x272 but after transcoding the size of the output video
> is
> > 320x240, as it plays on youtube.
> >
> > After digging a bit further it looks like the metadata that is added by
> this
> > patch adds the width and height as strings, so the Youtube player might
> not
> > be able to read it and hence uses the default size. The video plays fine
> the
> > only problem is that its squished into letterbox format because of the
> > metadata.
> >
> > After remove the patch it seems to work just fine, the metadata looks
> fine
> > and the size is also fine.
> >
> > For this test I used 'copy' codecs to eliminate all other possibility.
> >
> > I checked the metadata which is include below using flvlib (
> > http://pypi.python.org/pypi/flvlib/0.1.5). The output is included below.
> The
> > output shows that width and height are added as strings vs the original
> > 'in.flv' file where its double.
> >
> > So I guess the question is, should it be adding only the metadata that is
> > not already added like 'canseekontime' ? Because just above this patch in
> > the code there are quite a few places that add the metadata like width,
> > height,  audio/videodatarate, etc. so why add it again ?
>
> its a bug indeed, ive just fixed it, thanks for the report
>
>
Thanks Michael, that works for me.

-- Pranav


>
> [...]
> --
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
> The greatest way to live with honor in this world is to be what we pretend
> to be. -- Socrates
>