DVD-Lab .mpa and .mpv files smaller then mpg

[bravo]

Iv created a movie using Adobe Premiere and exported an mpg from it which is 3,192,901kb in size (Max bitrate 8000, target bitrate 6,600, min bitrate 5000)
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Im using DVD-lab to author my dvd,
DVD-lab multiplexs my mpg file to create .mpa and .mpv files.
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The size of the mpv file is 79,377 kb
The size of the mpa file is 2,338,726 kb
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The total size of the DVD once burnt is 2,601,564 kb.
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Now im confused because the DVD is smaller then my original mpg file, does this mean I have lost quality in my final DVD compared to my original mpg file?
Im assuming DVD-Lab has compressed my original file in some way.
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Is this a fault of DVD-lab, or do all authoring programs do this?

[benbryant]

Hi bravo,

It's normal the combined de-multiplexed .mpa and .mpv file size is smaller than the multiplexed .mpg file size because .mpg file which holds both video and audio contains more information about the file's structure, as explained in simple term. Please don't get nervous about losing quality.

Regards

[bravo]

Does this mean that i can increase the target, max and min bitrates even more? so even if the mpg file size is about 4.5gb, once its demultiplexed, the movie will still easilly fit onto a dvd

[benbryant]

No, the demultiplexing process is needed for authoring purpose. DVD-Lab will add additional information when authoring your movie into DVD

Regards