[FFmpeg-devel] [PATCH 1/3] closed caption decoder: accept and decode a new codec type of 'raw 608 byte pairs'

[Kieran Kunhya]

On Fri, 1 May 2020 at 04:59, Roger Pack <rogerdpack2 at gmail.com> wrote:

> On Thu, Apr 30, 2020 at 4:30 AM Kieran Kunhya <kierank at obe.tv> wrote:
> >
> > On Thu, 30 Apr 2020 at 07:22, Roger Pack <rogerdpack2 at gmail.com> wrote:
> >
> > > > > c9153590e5f167e41910d867639eb887164e28d2
> > > 0001-closed-caption-decoder-accept-and-decode-a-new-codec.patch
> > > > > From bf29fe5330e83e37cf064b18918185c6b00d9b9f Mon Sep 17 00:00:00
> 2001
> > > > > From: rogerdpack <rogerpack2005 at gmail.com>
> > > > > Date: Tue, 28 Apr 2020 05:15:15 +0000
> > > > > Subject: [PATCH 1/3] closed caption decoder: accept and decode a
> new
> > > codec
> > > > >  type of 'raw 608 byte pairs'
> > >
> >
> > How does this content exist? Are you defining your own file format with
> the
> > byte pairs?
>
> It's transmitted as "raw byte pairs" by analog TV broadcast in the US.
> https://en.wikipedia.org/wiki/EIA-608 has  details.
>
> I believe it transmits  one closed caption character (or control code)
> per frame (basically a single byte pair on "line 21") so it can do 30
> closed caption chars/second.  Anyway that's where it's originating
> from.  Good question :)
>

Yes, but these byte pairs are usually in a container or exist in an
analogue waveform.
Have you defined your own format of "raw byte pairs"? That doesn't exist in
the wild as far as I know.

Kieran