[M4IF Technotes] Sub-part of a presentation

[Richard Shields]

Hi Chris, all,
> There is a couple ways you can do this.
> Your main file has an IOD and BIFS and OD tracks.
> The OD track contains an OD command with the video OD and audio OD.
> One way is:
> Those OD's contain urls to the remote OD's.
> The remote file contains a root OD (not IOD). which has the 
> OD information for the Audio and Video ES's.

Where does this root OD exist in the remote file?  In the iods?  If so, the
iods can contain only one OD and a single OD cannot refer to both a video
and an audio stream.
> Another way is:
> Those OD's contain urls to the remote ES's directly in which 
> case the remote file doesn't need to contain any OD or IOD.

OK... the specification for the file format states that the iods is
mandatory.  Is that not true in this case?  Or can an iods exist but not
contain an IOD or OD?
> A third way:
> You can also have a remote URL contained in the file format 
> Data Reference atom.

-Richard