On 31/05/2011, at 09.08, Alex Converse wrote:

> On Sun, May 29, 2011 at 10:40 AM, Yusuke Nakamura
> <[email protected]> wrote:
>> 2011/5/28 Gil Pedersen <[email protected]>
>> 
>>> 
>>> The current code assumes that the first sample has the earliest
>>> composition time. When using b-frames, a codec is not required to enforce
>>> this, and thus I make a quick search for the sample with the earliest
>>> composition time. ISO/IEC 14496-12 section 8.6.1.1 has an open GOP example
>>> that illustrates this. As far as I can tell this composition time is what
>>> needs to go into "media_time" for proper sync.
>> 
>> Do you wish to start presentation from incomplete samples such as
>> undecodable leading samples, which are samples that have earlier composition
>> time than the reference I-frame has, and depend on the earlier GOP deleted
>> from the stream?
>> 
>> I think incomplete samples shouldn't be in any edit, i.e. whole
>> presentation, and you should add more delay by sum of duration of these
>> incomplete samples and set composition time of the reference I-frame to
>> media_time of second edit entry.
>> 
>> So, I think it is enough for you to only set track->cluster[0].cts to
>> segment_duration of the first edit with timescale conversion and to
>> media_time of the second edit.
>> 
> 
> I tend to agree with Nakamura-san's analysis of this.
> 
> Are B1 and B2 from the Open GOP example supposed to be decodable
> without reference pictures before I1?

You're right, just discard the second patch.

/Gil
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