[FFmpeg-devel] Mov / Mp4 Muxer in streaming

Baptiste Coudurier baptiste.coudurier
Sat Apr 18 23:10:12 CEST 2009

On 4/18/2009 9:16 AM, Marco Fucci wrote:
> Hi Baptiste,
>> About the concept. If I understood correctly you are writing one "mdat"
>> atom for every sample. I think this is not really efficient and it would
>> add a lot of overhead. Correct me if I'm wrong.
> Yes, this is the concept. We didn't find another to generate mp4 in streaming.
> The drawbacks are:
> _ more metadata (but not that much)
> _ I have read somewhere that not all players supports mutliple "mdat"
> atoms (but major ones seems to support it)
>> I think some buffering should happen, to ensure that seek won't be
>> needed, I believe this can be done by checking ByteIOContext buffers status.
> You mean to group multiple frames in a "mdat" atom ? Or I haven't
> understood correctly ...

Yes, you can buffer some data, to have the size of mdat to write then
you write it with its size without seeking back.

The problem is only seeking.

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