Streamline MPEG-2 playback to edit

Eug7 wrote on 7/14/2003, 7:12 PM

I have a converted from VOB MPEG-2 movie, about 6-gig. The file wont play in 4.c well at all. playback will freeze on a frame while the audio continues so I know the software is trying to play but can't catch up with the current frame. I've changed preview to draft mode to no avail. Is there a method to improve playback in order to edit the project? Is there a prerender? If I do a prerender with it become invalid when I begin to edit (split, transitions) and slow to a crawl again? I tried a smaller MPEG-2 about 1/4 the size. Results are the same.

CPU: 1.6
RAM: 512

Comments

Chienworks wrote on 7/14/2003, 7:21 PM

The problem is that you're trying to work with an MPEG file. MPEG is compressed temporally, which means that many of the frames are incomplete and depend on data from previous frames. When Vegas displays a frame it often has to backtrack through many previous frames to generate a full display of the current frame. This can take a lot of time, as you are noticing.

Convert the MPEG file into AVI before you try editing. You can do this in Vegas by simply rendering to AVI (probably the DV template is a good tradeoff between file size and quality). Then use this new AVI file for editing.

mikkie wrote on 7/15/2003, 8:49 AM

Go to doom9.org, digital-digest.com, dvdrhelp.com -> download and install dvd2avi & vfapi -> open the mpg2 in dvd2avi -> hit preview and watch the info window -> if film greater then 95% select force film -> optionally go through the audio dialog to save audio etc., though many do this elsewhere (see guides at mentioned sites) -> save your dvd2avi proj (takes just a few minutes) -> open your saved dvd2avi proj file in vfapi and convert it to a fake avi file (takes seconds) -> open this new file in Vegas or any other editor. Depending on your desired destination for your proj, can also do a conversion to PC color space.

Problem will be solved, though playback might not be as good as with an avi, but much higher qual & Much less time getting there. It will also render much better, IMO, as VV4c doesn't like to handle the rendering/re-rendering steps it has to go through as Chienworks explained. While dvd2avi was designed for obvious reasons, I use it for everything mpg2 imported into Vegas without complaints.

Eug7 wrote on 7/15/2003, 10:40 AM

Thanks Chienworks & mikkie. My concern was that if I took the original VOB and converted to AVI & then author/burn (rendering from AVI to MPEG-2) that there would be some quality loss. Is it my understanding that creating a fake AVI file is in essence a pointer to the MPEG file & that Vegas 4.0c is really rendering the MPEG-2 after edit during the author/burn?

mikkie wrote on 7/15/2003, 11:11 AM

"Is it my understanding that creating a fake AVI file is in essence a pointer to the MPEG file & that Vegas 4.0c is really rendering the MPEG-2 after edit during the author/burn? "

Correct

Eug7 wrote on 7/15/2003, 3:15 PM

mikkie,
DVD2MPG makes from what I can tell an AC3 seperate audio file or you can select to make a .wav. Is thei the file that's ends up as the final audio in the render or with Vegas use the file in the VOB?