Re: ACTION-245: Implementation of Media Fragments from Dailymotion

Dear Pierre Yves,

> For the ISO MP4 container (+ AVC/AAC codecs), serving the codecs setup data (AVC SPS/PPS and AAC setup) and the raw
> samples is not enough, since there is no DTS/PTS information in the raw samples area (samples are just ... well, raw
> data, sample after sample, audio and video samples interleaved in the file). You need to rebuild and provide some
> time/space index tables (namely stts/ctts/stsc/stsz/stco/stss atoms, see ISO 14496-10).
>
> So maybe you meant codecs setup data _and_ these index tables by "codec setup data". Otherwise these recipe won't work
> for ISO MP4.

Thanks for raising this issue. Indeed, we never really defined in the 
spec what we mean with the term 'codec setup data'.
 From our point of view and as Davy clarified it in another thread, it 
consists of:
  - setup data for the decoder (such as resolution, quantification 
parameter, ...);
  - timing information (i.e., when to display a certain frame);
  - track information (i.e., which tracks are present and how does the 
raw samples relate to these tracks).
So it _does_ include the index tables you are referring to which makes 
"workable" the recipe.
Best regards.

   Raphaël

-- 
Raphaël Troncy
EURECOM, Multimedia Communications Department
2229, route des Crêtes, 06560 Sophia Antipolis, France.
e-mail: raphael.troncy@eurecom.fr & raphael.troncy@gmail.com
Tel: +33 (0)4 - 9300 8242
Fax: +33 (0)4 - 9000 8200
Web: http://www.eurecom.fr/~troncy/

Received on Friday, 13 January 2012 07:44:10 UTC