[FFmpeg-devel] [PATCH 1/2] avcodec/libzvbi-teletextdec: add support for selecting subtitle pages only

[Marton Balint]

On Wed, 13 Jun 2018, Jan Ekström wrote:

> On Wed, Jun 13, 2018 at 12:47 PM, Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>> 2018-05-06 23:05 GMT+02:00, Marton Balint <cus at passwd.hu>:
>>
>>> +List of teletext page numbers to decode. Pages that do not match the
>>> specified
>>> +list are dropped. You may use the special @code{*} string to match all
>>> pages,
>>> +or @code{subtitle} to match all subtitle pages.
>>
>> Shouldn't this default to "subtitle"? The current default is useless iirc.
>>
>> Carl Eugen
>
> I think one of the major problems is that IIRC currently the receiving
> end has no idea for which page a subtitle was received for (be it
> image or text).
>
> Not only would it let the default be * (in case someone wants to
> render teletext on the screen in general), but also there are channels
> where a single teletext stream has at least two or three different
> subtitle pages, and if the API client would be able to distinguish
> between them without making multiple decoder instances I'd think
> that'd be neat.

Some side data would be good to specify the originating page number, 
but AVSubtitle has no side data. I guess this will have to wait until the 
AVSubtitle -> AVFrame conversion happens...

Regards,
Marton