[FFmpeg-devel] [PATCH] Using struct for StyleRecords and implementing support for large boxes(>32 bit) for 3gpp timed text

[Niklesh Lalwani]

On 26-Apr-2015 10:46 AM, "Philip Langdale" <philipl at overt.org> wrote:
>
> On Sun, 26 Apr 2015 05:04:07 +0200
> Michael Niedermayer <michaelni at gmx.at> wrote:
>
> > On Sun, Apr 26, 2015 at 08:22:56AM +0530, Niklesh Lalwani wrote:
> > > On Sun, Apr 26, 2015 at 6:56 AM, Michael Niedermayer
> > > <michaelni at gmx.at>
> > > > wrote:
> > > >
> > > >>
> > > >> > +struct __attribute__((__packed__)) StyleRecord {
> > > >
> > > >
> > > >> you cant do this
> > > >
> > > > attribute packed is not ANSI/ISO C
> > > >
> > > >
> > > >> How do I implement packed structures then here? ( since I don't
> > > >> want
> > > padding for proper alignment with the text sample)
> >
> > you cant create packed structs, theres no portable way to do so
> > also there likely would be issues on either big or little endian
> > with such structs if they where used for reading data
>
> You're right. This was my suggestion. Niklesh - you can still use the
> struct, but you'd have to read the members of the struct out one by
> one. It's not clear whether that provides any meaningful benefit. You
> still end up losing the benefit of being able to directly address the
> styles. I think we have to abandon this approach. Sorry.
>
> --phil
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No problem. I had never used packed structs before so it was good to learn
about them. So should I just post the patch for implementing support for
large boxes for now?

-Niklesh