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redpill
2008-08-22, 04:03 AM
I recevied a show on a DVD that was tranferred from an 8mm master tape. Not sure of the method used to transfer. The show is 1 hour and 45 min and takes up 4.0G on the DVD. Using Vegas, I imported the video and synced it with audio from a separate source that I received on 2 CDs. If I want to keep it so the show fits on a single layer disc, what's a good bit rate to use to render? I used a variable bit rate of 8,200,000 max, 8,100,000 avg, 8,000,000 min kb/s and I ended up with 8G. Would it be better to just leave it as is and author to a dual layer disc?

pawel
2008-08-22, 05:12 AM
Quality of re-rendered video will decrease as mpeg format is lossy - it's like double encoding mp3. You should demux and leave video as it is now, and add (mux) to it synced audio.

105 minutes of video and audio in LPCM format of a DVD5 would require to render video at 4276 kbps average. If you save audio in Dolby 192 - 448 kbps, average video bitrate can be raised to 5600 - 5300.

8100 kbps everage is nonsense as the quality of your source is not at this level.

KoolKat
2008-08-22, 05:36 AM
This may help you for the future redpill.

HERE (http://www.videohelp.com/calc.htm)

K_K

saltman
2008-08-22, 08:21 AM
Don't re-render it. go the demux route to preserve quality. re-rendered video is not allowed here BTW if you were planning on sharing it here. the demuxed route one would be.

and yes blowing it up from what it is to something higher would not improve quality. it would only make the files bigger.

redpill
2008-08-22, 03:57 PM
Thanks for the quick responses.

I'm not sure what is meant by demuxing. If I don't re-render, then what is the process? Here's what I'm guessing.

Import mpg files from DVD into Vegas.
Sync audio.
Render audio track as wav (LPCM).
Insert media (mpg's) into DVD Architect.
Insert wav file into Architect.

saltman
2008-08-22, 04:16 PM
vegas will not accept the .vob files from the dvd.

you will have to open it with tmpgenc (or similar) and demux (demultiplex) the .vob files into the elementary streams. m2v and wav (or ac3). import these files into vegas. align both audios. trim the new one to match the old exactly. then use the m2v and the new wav in DVDA and make your menus. You will be stuck with the original 2 discs. but you will have the best video. and new audio.

pawel
2008-08-22, 04:58 PM
Freeware demultiplexers: DGMPGDec (http://www.videohelp.com/tools/DGMPGDec), ProjectX (http://www.videohelp.com/tools/ProjectX), eac3to (http://www.videohelp.com/tools/eac3to)