[M4IF Technotes] B-frames in Simple? Which Levels?

[Ben Waggoner]

Rob,
    Thanks.
    I'm looking at a ton of encoders, and most of them aren't at all clear
as to what profile their output is compatible with.  And the various players
aren't any better about documenting what profiles they actually support.
Clearly, interoperability between players and encoders from different
vendors isn't right now, but it's very hard right now to tell if this is the
fault of the encoders or the players (I'm guessing it's mainly the players).
    For example, it looks like the Philips WebCine Encoder is Simple or
better, unless you have B-frames, in which case it requires Advanced Simple
or better.  But the Philips WebCine Player can't play other Simple or
Advanced Simple content produced by other encoders.
    Are there any kind of validation apps I can run on an .mp4 file that can
tell me what it needs to run?
Ben Waggoner
Interframe Media <http://www.interframemedia.com>
Digital Video Compression Consulting, Training, and Encoding
on 1/23/02 3:03 PM, Rob Koenen at rkoenen   intertrust.com wrote:
> Simple, Advanced Real-Time Simple (ARTS) don't hae it
> ( and Simple Studio and Core Studio on the high end. )
> 
> Whether or not B frames are supported is exclusively determined by
> the Profile.  Within the Profile, the level definition doesn't
> change it.