DVD burning

[Bynot]

I have just got pioneer ao3 dvd writer which comes with mydvd & instant cd/dvd. If I want to copy a dvd film onto a blank dvd. Is it better to encode into an mpeg format or to split the vob files and put it on to 2 blank dvd/r disks or is there a way I can only take the vob files which only contain the film and not the extras, so the fit on one blank disk. Any help or pointers to tutorials would be a great help.

many thanks,

Bynot.

[Darkbird]

At least you have a good grasp of the problem, unlike a lot of eager beaver dvd copiers out there. *grin*

If the total size of the DVD files is less than 4,700,000,000 bytes then no problem, just decrypt and burn. But a lot of movies (most ?) are larger than this.

If the movie VOB's, it's IFO/BUP and the main disk menu VOB and IFO/BUP files can fit on a DVD-R, then you can get away with leaving out the other VOB's and IFO/BUP files for the Extra's (making of the movie, behind the scenes, etc). As long as no one tries to select those from the menu while playing.

Otherwise, as you have said, you need to either re-encode the video to a lower bitrate to reduce the size, or you must edit (cut) the movie to fit on two or more discs. Either way, you have to go thru the process of authoring a DVD disc with authoring software like MyDVD. If you have money to burn or a cheap source for discs and don't mind swapping discs, then the editing (cutting) route is easier and faster. Because the price for DVD-R discs is still pretty high, I'd recommend re-encoding the video.

With a good mpeg encoder, the video will still look pretty good with the bitrate as low as the 2.7Mbps to 3.0Mbps range at full-res (NTSC 720x480). You can go that low for a long long movie, otherwise use more Mbps to get better video.

If you really want to save on the price of discs, then you can put two movies on a single disc. For that, I've been using what's called half-D1 format which is half the normal width (NTSC 352x480) and take the bitrate down even lower, close to the SVCD bitrate range of 2.0Mbps to 2.5Mbps.

Let's say you have two ninety minute movies that you'd like to put on a disc. That's 180 minutes times 60 for 10,800 seconds total play time. There are 4,700 million bytes on a DVD-R; subtract a 100 million bytes for use with menus and such; which leaves 4,600 million bytes. Multiplying by 8 gives us 36,800 million bits. Now divide the bits (36,800) by the seconds (10,800) which gives us 3.407 million bit per second to play with. VOB multiplexing has about 3 percent of overhead, so divide 3.407 by 1.03 to get 3.307 million bits per second for video and audio. If you only have one ac3 audio track per movie that is recorded at 384Kbps, then subtract 0.384 from 3.307 which leaves 2.923 million bits per second (Mbps) for video. Rounding off gives a nice figure of 2.900 Mbps, which is still enough for decent video that's properly encoded. I've intentionally fudged some the calculations to get a lower result so that I don't make a set of files that won't fit. i.e. you probably aren't going to have 100MB of menus. If you create a moving menu instead of a still menu, then add the length of the menu video into the total movie size.

Hope this helps you get started.

[Bynot]

Darkbird,

Many thanks for all the info it has given me a great starting point, to go off and give it a try.

Once again thanks for all your help,

Cheers,

Bynot

[Taxidermista]

Have you said "lower bitrate"? Maybe you would like to check out a little utility that could be interesting in this matter. It's a mpeg2 "transcoder", ReMPEG2. This is a Doom9 guide.