Support access units without AUD

[shaka-project]

Support access units without AUD

[kqyang]

It looks like the stream does not have AUDs (Access Unit Delimiter), which we expect to see in every Access Unit.

We'll take a closer to see if it is legal (spec compliant) to do that.

@tinskip, any thoughts?

[tinskip]

IIRC the leading AUD requirement depends on whether the video bitstream is
a Unit Stream (ISO-BMFF mostly), or Byte Stream (or Annex B, MPEG-2
containers). I am pretty certain it is required for the latter. But we
can probably relax that restriction.

On Thu, Oct 29, 2015 at 1:30 PM, Kongqun Yang [email protected]
wrote:

It looks like the stream does not have AUDs (Access Unit Delimiter), which
we expect to see in every Access Unit.

We'll take a closer to see if it is legal (spec compliant) to do that.

@tinskip https://github.com/tinskip, any thoughts?

—
Reply to this email directly or view it on GitHub
#47 (comment)
.

Thomás Inskip | Software Engineer | [email protected] | [phone]

[kqyang]

"ITU-T H-264:2014 7.4.1.2.3 Order of NAL units and coded pictures and association to access units" defines how access units can be extracted, which allows access unit delimiter NAL unit to be omitted from access unit. @TheModMaker is working on a fix.

[TheModMaker]

Now it will be able to determine access units without an AUD. However, the file you provided still will not work because it has timestamp errors. Several frames have a DTS the same as a previous one. If you pass it into ffmpeg, it will give warnings about invalid timestamps, and it will make a guess.

[peyoh]

Hi TMM,
I'm unable to test it because I no longer use gstreamer. If you are sure, that this enhancement is done, please close the case.
Cheers!