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Old 2005-01-31, 08:52 AM
4candles 4candles is offline
Join Date: Nov 2004
Re: Question about standalone DVD recorders - AC3 & PCM?

I think we're both just being overly pedantic.

The problem is that the phrase "mpeg file" is very vague - the MPEG standards define (at least) the following types of files:

1) A file containing a single elementary video or audio stream. A ".mp3" file is an example of an MPEG elementary stream.

2) A file containing an MPEG program stream - a collection of video and audio elementary streams multiplexed together, possibly with other data such as subpictures. Used on DVDs (.vob files are essentially a constrained subset of program streams with extra DVD-specific private data).

3) A file containing an MPEG transport stream - similar in concept (but not in structure) to a program stream, but can contain more than one program. Used in digital TV broadcasting.

I always work with the raw elementary streams when authoring DVDs, and then multiplex them together at the very end, when I am ready to author the DVD. Hence when someone says "video file", I always think of an elementary video stream, and not a program stream - which is how this conversation started. I also think of the compression and multiplexing as two distinct steps in the process, even if your software combines the two.
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