[FFmpeg-devel] H264: mp4toannexb BSF and streaming

[Alexandre FERRIEUX - FT/RD/SIRP/ASF/SOFTL]

On 18/08/2010 16:13, Benjamin Larsson wrote:
> On 08/18/2010 04:06 PM, Alexandre Ferrieux wrote:
>> On 18/08/2010 15:33, Alexandre Ferrieux wrote:
>>>
>>> What I'm trying to do is understand where these "important" extradata
>>> are in the 3GP chunk hierarchy:
>>>
>>> - either they already in a separate chunk that is non-causal (comes at
>>> the end of the stream), and I'm doomed.
>>>
>>
>> Further experiments with varied clip durations, sadly show that the
>> above holds :(
>>
>> Indeed, the produced .3gp files contain a few O(1) blocks (which
>> deserve the name of 'header' or 'trailer'), but also unfortunately
>> *two* O(N) blocks: 'mdat' for main bitstream, 'moov' for extradata.
>> There being more than one toplevel chunk O(N) in size, with important
>> data in both, wipes any hope of live streaming. Good job, whoever
>> designed that :/
>>
>> -Alex
>
> qt-faststart in the tools directory can move the it around. As long as
> you can control the stream you should be able to handle it.

Again, regardless of the order, only one chunk growing linearly can be transmitted "live".
This utility cannot move the 'moov' before it is generated by the sender (at the end of a live camcorder session).

-Alex