HLS: support PES packets across TS boundaries

[jeroen]

There's various branches of an open source segmenter that can create Apple HLS files, but there are a few differences between its implementation and those of Apple/Wowza:

• Audio elementary streams don't have an ID of 448, but 445 (fixed by supporting in framework)
• ADTS headers contain an MPEG2 streamtype flag instead of MPEG4 (fixed by supporting in framework)
• TS fragment don't start with a keyframe. (fixed by ignoring non-IDR frames upon switching)
• TS fragments start with PES data from the previous TS fragment (indicated by non-zero continuity counter).

The last issue can be fixed by decoupling the PES parsing from the TS loading. Needs a bit of a rewrite though. For now, the issue is logged in the framework:

Discarding TS [audio|video] packet without PES header.

Test videos that have this issue include:

• Presentation
• Zencoder
• Serenity
• Talent

[jeroen]

Squeeze uses the HTTPSegmenter tool for building the TS files:

 http://code.google.com/p/httpsegmenter/

Having support (in or for) this tool will fix this issue for a wider variety of tools.

[jeroen]

As part of this, we should also ensure the entire video is not kept in memory anymore. Not really needed ...

[jeroen]

Implemented by Courtenay...