[vlc-devel] Smooth Streaming

Christopher Mueller christopher.mueller at itec.uni-klu.ac.at
Fri Aug 19 17:47:13 CEST 2011


> On Fri, Aug 19, 2011 at 1:14 AM,  <cmueller at itec.uni-klu.ac.at> wrote:
>> Have you installed the DASH plugin correctly?
>
> Yes I have, and it works well.
>
>> The output doesnt look like that.
>
> It's only part of the output, and I don't get this messages with a
> normal MPD file.

Normaly the plugin should open the the urls and simply handover the
segments to the avformat demux. So on the ouptput you should see some
error messages from avformat demux instead.

>
>>
>> Anyway its not possible to simply pipe MS Smooth Streaming fragments
>> into
>> VLC because they do not use a initialization segment with a "ftyp" and
>> "moov" box as recommended in the iso base media format standard in Annex
>> C.7. The first segment of a MS Smooth Stream which is in your example
>> "http://mediadl.microsoft.com/mediadl/iisnet/smoothmedia/Experience/BigBuckBunny_720p.ism/QualityLevels(350000)/Fragments(video=0)"
>> just contain a "moof" and "mdat" box because it is a fragment ;).
>
> Ok I understand now... Thank you very much for your explanation !
>
> What I still don't understand is why the Smooth Streaming server
> doesn't send this initialization segment, but I have to get a better
> understanding of containers.

They init the stream with the information from the client manifest but
this is just a guess.

>
>> So what
>> you can do is create an init segment for that stream or init the demux
>> with the information from the manifest file by yourself.
>>
>
> Do you happen to have links to documentation that could explain how to
> do that ? I didn't find good doc about MP4 / ISOFF in general. Maybe
> should I play with MP4Box to get a better understanding to this
> container ?

Maybe you should take a look into the standard ;)

ISOBMFF MPEG-4 Part 12, ISO/IEC 14496-12
MP4 MPEG-4 Part 14, ISO/IEC 14496-14

Best Regards
Chris





More information about the vlc-devel mailing list