Re: [MSE] Establishing the Presentation Start Timestamp

On Jul 25, 2012, at 2:58 PM, Steven Robertson wrote:

On Tue, Jul 24, 2012 at 9:38 PM, Mark Watson <watsonm@netflix.com<mailto:watsonm@netflix.com>> wrote:
Which DASH BMFF media are you referring to ?

Content produced by the GPAC/MP4Box tool, including the selection of content prepared by the GPAC organization as a conformance test; content produced by YouTube's encoding infrastructure; and a small set of demonstration files I have received from Netflix (nflx_short_a_0064, nflx_short_v_0560, nflx_short_v_1050).

Using the Edit List would make sense, but we better start filing some bugs against DASH muxers if we want it to be there ;)

Yep, probably we should ;-)

Just to be clear, though, there isn't really a problem unless you have a mixture of files with different depths of frame re-ordering. It's frame re-ordering that forces you to have a non-zero Composition Offset for the first video frame. If all your files have the same first frame Composition Offset then you're good to go without edit lists - they are time aligned (You might need to offset the Audio to align that, though). If you have a mixture, though, then you're going to need Edit Lists in some of them to get everything aligned on the same timeline.

…Mark