? about VOB extensions

[Edward Troxel]

I VOB file is what is required for a DVD. You give any authoring program an MPEG2 file, author the DVD, and it will produce a series of VOB files.

Edward Troxel

[Steven J casey]

So a VOB is actually an MPEG2 file modified for a DVD player to recognize it on the disc, as opposed to a plain-jane MPEG2 that could play on a PC?

Also, my brother is getting into all this as well and sent me this question.
I put a 30 minute MPEG2 file in Vegas and cut off the beginning and end of the file. Then told it to “Render As” a new MPEG2 file with the exact same settings as the original file. It took 40 minutes to process the file. But with DVD Architect it takes 20 minutes to process two 30 minute files – so basically 1/4th the time.
First, he’s recording TV shows for his daughter using software that records as MPEG2, but isn’t he losing quality by recompressing MPEG2 in the render? I’m not sure what’s going on with the render times though.

thanks again,
Steven

[Edward Troxel]

When he rendered the MPEG2 file in Vegas, it had to decompress and recompress EVERY frame. With DV-AVI it does not have to do that – It just copies any unchanged frames. With a compressed format such as MPEG2, even if the settings are exactly the same, it has to totally render everything.

Yes, he is losing some quality. Maybe not enough to notice in one render (depending on the initial quality) but he is definitely losing quality. For the best quality, record as DV-AVI and then edit and render as MPEG2 for the final output.

Edward Troxel

[Steven J casey]

Thanks for the info!

Steven

[Jerry Waters]

Try the programs at http://www.womble.com

They allow editing mpg without reencoding and work very well and very fast.