Is it possible not to multiplex?

Gabbon · Post by **Gabbon** » Thu Sep 14, 2006 12:40 am

Hi,

my question probably betrays my ignorance, but here goes...

I encode my video prior to authoring using Cinema Craft Encoder.
I've tried video encoded as system streams as well as elementary streams, and both have to go through the video/audio multiplexing stage of the DVD creation process. I don't understand.

Why should mpeg2 video that has been already encoded with audio and video muxed (as a system stream) need multiplexing? On top of this, Ulead crashes on some of the mpeg2 video files encoded as system streams.

Any guidance would be great,

Thanks.

DVDDoug · Post by **DVDDoug** » Thu Sep 14, 2006 10:53 pm

Why should mpeg2 video that has been already encoded with audio and video muxed (as a system stream) need multiplexing?

If you check the box that says Do Not Convert Compliant MPEG Files, nothing should be done to them unless they are not DVD compliant, or unless Movie Factory thinks they are not compliant. If you don't check that box, it's going to convert the files per your Project Settings.

On top of this, Ulead crashes on some of the mpeg2 video files encoded as system streams.

All of my crashes (and "lip-sync" problems) have been caused by corrupt MPEGs. It can be hard to tell if you have a bad MPEG... All of my bad MPEGs played fine, but they caused trouble during re-coding or re-multiplexing. So, I call it "sneaky corruption".

Gabbon · Post by **Gabbon** » Fri Sep 15, 2006 3:14 pm

Thanks for your reply.

DVDDoug wrote:
Why should mpeg2 video that has been already encoded with audio and video muxed (as a system stream) need multiplexing?
If you check the box that says Do Not Convert Compliant MPEG Files, nothing should be done to them unless they are not DVD compliant, or unless Movie Factory thinks they are not compliant. If you don't check that box, it's going to convert the files per your Project Settings.

Yes, I checked that box, and it does not look like it is re-encoding either the video or the audio (good!), but I don't get why multiplexing is necessary when I input system stream mpeg2 (that has been muxed already)

On top of this, Ulead crashes on some of the mpeg2 video files encoded as system streams.
All of my crashes (and "lip-sync" problems) have been caused by corrupt MPEGs. It can be hard to tell if you have a bad MPEG... All of my bad MPEGs played fine, but they caused trouble during re-coding or re-multiplexing. So, I call it "sneaky corruption".

Thanks for your input on that one--quite annoying that encoders can get it wrong on first go... but that's what can happen, I guess.

snoops · Post by **snoops** » Fri Sep 15, 2006 9:25 pm

Your program stream is not multiplexed for DVD. For DVD the streams need to be muxed into VOB files that are program streams with navigation and search information. VOB also allows for other DVD features not found in a simple program stream.

This is a good source for almost all answers to DVD questions (create a bookmark, or a favorite if you use that browser):
http://www.dvddemystified.com/dvdfaq.html

Gabbon · Post by **Gabbon** » Fri Sep 15, 2006 10:06 pm

Thanks