#56 Add suboption to -dash to restrict separation of Sample Group Descriptions

[Greg Rutz]

As discussed in thread [e9fb3111], I am trying to get encrypted DASH content to play in Internet Explorer 11. Microsoft requires that MP4s comply with DECE Common File Format (CFF). One of those restrictions (according to Microsoft) is that the 'sbgp' and 'sgpd' can not be split between the sample table in the 'moov' and the 'traf' as is allowed by ISO BMFF.

To support this, I propose adding a new suboption to -dash called "-no-split-sg-boxes". When this command is specified, the 'sgpd' boxes will not be cloned from the input 'moov' tracks. Instead they will be duplicated in the corresponding 'traf'.

A proposed patch is attached.

As an alternative solution, if you think it would be better to have a "-cff" option that ensures compliance with any other CFF-specific limitation, I would be open to that. I am in the process of trying to obtain the CFF conformance software from DECE. With that, I can try to find any other CFF non-compliances of MP4Box-generated content.

[Greg Rutz]

Looks like this feature was implemented in rev 5119 via the "sample-groups-traf" switch. Thank you.

[Greg Rutz]

However, as part of this fix, we need to handle the fact that sbgp group description indices must start at 0x10000 when the sgpd is in the traf. Attached is a proposed fix.

I'm not quite sure if the MergeTrack function in src/isomedia/track.c also needs to account for the different indexing. Might need to look at that one some more.

[Jean Le Feuvre]

This should now be fixed on SVN could you give it a try

[Greg Rutz]

Working now. Thank you! OK to close.