Friday, July 11, 2008

All Time High

I've mentioned Divx a few times, and have been meaning to post a "how to" on converting movies to the format.

Why would one do this? Well, it's almost exactly like converting songs to MP3. You can get a whole movie, in decent quality (a scootch better than VHS), on a CD, about 700 Mb. If you want to have a bunch of movies on your PC for traveling, this is the way to do it. They also sell home DVD players that play the format, so you can watch them over your home theatre as well.

Another great feature is that you can use the Divx editing package to edit and create custom versions of things. It's limited in that you can only splice things together - or splice segments out as an excerpt - as if you were editing developed film, but still, it does allow for some fun.

For instance, it dawned on me that I could finally make something I've always wanted to see (and buy had they ever made it): a DVD that is just the opening title sequences to the Bond films, with the silhouettes of nekkid females jumping around to Sheena Easton, Garbage, and Rita Coolidge. It would make a great party vid because you'd have music playing, and those who were in the midst of a lull in conversation could tune into the TV until some new cocktail party chatter bubbled up.

So, I got the box sets from the library, ripped the DVD, converted the first .VOB file (more on that below) to Divx, and then edited them together in the Divx Author. It's even better than I thought it would be. I can't wait to have a party just to show it off.

Here's one to jog your memory:

Anyway, here's how you do it:

First, you need a good DVD ripper, which is a program that converts the DVD files - which are in .VOB format, a form of MPG/MPEG format - and removes the copy protection. Once you've done this, if you can burn DVDs, you can essentially create a straight copy (menus and all) that doesn't have copy protection and without all the FBI Warnings about not copying things. However, the goal here is to convert them to Divx.

The best DVD ripper is DVDFab, which is a commercial package, but it lets you rip DVDs for free without having to buy the advanced features. How cool is that? I certainly am going to buy the package in the near future, because I want some of the extra features, but for now it does what I need.

The next best one is a freeware package called DVDshrink. The only reason I don't recommend it above DVDFab is that it's older, and some of the new copy-protection schemes trip it up. And, the commercial package is just easier to use and is better at naming files and directories, as a commercial package should.

If you have the room, install both. I've found that when one package can't copy the DVD for some reason, usually the other one can.

After you have your .VOB files, you then turn to the Divx converter. Divx is a commercial package, but you can download all of their software for free. A little Googling will also get you the activation codes if you need them before you pony up the cash.

So, first rip the DVD. This shows the DVDFab ripping screen:

You can rip the whole disc or just the movie. I usually rip just the movie, because that's all I really want. If you want the bloopers and stuff, rip the whole disc. In this graphic, note that two whole versions are available, the widescreen 16:9 (Title No. 2) and the full screen 4:3 (Title No. 10).

On the right is the audio track and subtitle selection section. I usually deselect everything except the main soundtrack, which is the one you see at the top right (Type AC-3/5.1). It's usually obvious which one it is. The other audio tracks are usually director's commentary and such.

Some systems may need the AC3 filter (free). AC3 is an audio format used on DVDs. I also just discovered the Divx converter can't handle PCM audio, so make sure you don't have it selected when ripping the DVD.

The less info you have for Divx to compress, the better the final product will be. However, if you want the commentary track and subtitles, Divx can convert them and play them back, so keep them if that's your thing.

If you're just going to copy this onto another DVD, by all means, grab everything available so it's just like the official DVD.

Here's DVDshrink:

This is the "rip the whole thing" screen with the selections for audio and subtitles.

Here's the "just the movie" screen. I had to watch portions of the two available to tell which one was the widescreen, which is my preference. This is where DVDFab is a little better, because it spells it out on the screen for you. You have to double-click the titles you want converted so they show up on the left, under the "DVD Structure" area. (Title 2 was the widescreen version.)

Now that you have your .VOB files, open the Divx converter:

Drag the first .VOB file to the Divx window, where it indicates. You don't grab all the .VOB files, because Divx figures out that the other files (2, 3, and 4) are the continuation of the movie. Both of the DVD rippers chop the movie into 1 GB chunks (and they're that way on the DVD, too). Because of this you do not want to rename the .VOB files before you convert them with Divx.

Once the converter analyses the files, it pops this screen:

Here you select or deselect all the audio and subtitle stuff you want or don't want. I use the "Maintain source audio" selection when I'm converting a DVD that's mostly music (like concert DVDs), and if during the first conversion the audio does not match the picture (this happens sometimes). This will sometimes correct the audio being out of sync. I don't use it for regular movies, because it compresses the video better when you don't maintain the source audio. However, during dynamic sequences you can hear some of the warbling artifacting that MP3 does when there's too much to compress. It's rare though.

Then you want to make sure you come to this screen, select the "Limit Filesize to" and select 700 MB, so it will fit on a CD:

If you are never going to back them up on CD, and are just going to have them live on your hard drive for movie watching while traveling, you may want to NOT choose this option and let Divx choose the size for you. It will vary between 1 GB and 1.4 GBs usually (twice the size of a CD). You get pretty good quality at 700 MB for most flicks, though.

If the movie is a straight talky or a comedy without any big visual effects sequences, say like Good Will Hunting, Jersey Girl or About a Boy, you can even scrunch them down to 350 MB so two will fit on a CD.

The one type of film that does not covert well is animation; you get a lot of pixilation. I suspect it's because the way video compressors work: first they establish a shot using the initial frame of a sequence, and then subsequent frames are only the information that has changed from the last frame. When it's a live-action movie with a lot of detail, there's more pixels to swap out, hence it looks better. But with animation, you have huge swaths of one color, and so the compressor assigns the same value to a lot of pixels, and thus you begin to see big squares that are one kind of red (for instance) with an obvious square border next to another swatch of slightly different red. This also happens in underlit and dark scenes in live-action movies, too. However, you typically only notice it if you're watching the movie in the dark and your eyes can pick out the borders between various blacks.

And there you have it. Happy compressing!

1 comment:

Anonymous said...

Dude, could this work to get songs off a concert dvd into .mp3's?