[foms] HLS and HLS patents
jeroen at longtailvideo.com
Mon Oct 18 02:28:28 PDT 2010
On Oct 15, 2010, at 8:17 PM, Andoni Morales wrote:
>>> They have also pointed me to the MPEG effort in the space, which is
>>> supposedly media file format independent. There is no public spec
>>> available at this stage and it is unclear what the rights situation
>>> will be. But I was told it builds on the 3GPP spec in this space. That
>>> is available at
>>> http://www.3gpp.org/ftp/Specs/archive/26_series/26.234/26234-940.zip .
>>> The file format is called "MPD" for Media Presentation Description and
>>> below is an example. I am rather un-excited by its complexity in
>>> comparison to m3u8 actually:
>> It's also worth looking at the stuff from Microsoft as well. In fact,
>> there's a chance (without having talked to them) that they might want to
>> standardize something that's similar to how Smooth Streaming works, at
>> least on the client. It will be good to have a partner here, be it
>> Apple or Microsoft.
> For live, Microsoft's solution is lighter than Apple's one.
> Apple's playlists are updated each fragment duration, which means two
> request for fetching a fragment: one to update the playlist and a
> second one for the new fragment. Instead, using Microsoft's manifests,
> the client downloads the manifest once and it builds the playlist
> on-the-fly using the information stored in the uuid box, which has a
> lookahead for two fragments
> Apple's playlist are much easier to generate and it's easier to handle
> discontinuities or doing load balancing, but building the playlist
> on-the-fly like Microsoft does might reduce considerably the number of
> request to the server.
Microsoft's solution is indeed technically more elegant than Apple's. However, it is also more difficult to build - one needs specific encoders that set the UUID's and playback clients that process the UUID's. Apple's solution is a waste of bandwidth - pinging the manifest time and again - but it requires nothing special compared to an on-demand setup.
And when the live event has ended, the live stream simply is the on-demand stream.
More information about the foms