I gave a short presentation last night at uphpu on ripping and encoding DVDs under Linux. I wanted to type up a few notes on some stuff I mentioned during the meeting.
Short version: Use Handbrake (available on Linux, Mac OS X and Windows). I’ve gone through a lot of applications through the years trying to find that “perfect rip”, and Handbrake beats everything hands down. I’m a videophile who likes everything looking as nice as it can, and this is what I use regularly.
Accessing DVDs
The first things you’ll need installed on your box is libdvdread and libdvdcss. libdvdread will access the DVD filesystem, and libdvdcss will decrypt the DRM on the disc. These should both ship with your distro, or if they don’t, should be relatively easy to acquire.
I use a lot of command line tools to access DVDs, so my focus was on that. The reason for that is because I have a lot of shell scripts to rip my massive library of discs, and I store data about them in a database.
lsdvd is the first stop. A very small app that uses libdvdread to display human and script-friendly output of the details of your disc.
mplayer dvd:// and mplayer dvdnav:// plus the optional track (dvd://3) or optional -dvd-device argument to specify the location of the device or ripped ISO.
I use dd to copy the contents of the entire disc to the harddrive and then rip it from there, to avoid wear and tear on the DVD drive, and also because I can do things like simultaneously rip one disc in the background and encode another at the same time.
When accessing the drive, you’ll want to use mplayer or some other program to access the drive and decrypt the CSS so that the drive itself caches the access. Otherwise, it may lock up.
I use pv to dump the disc and give me a pretty progress bar with ripping ETA and disc read speed: pv -ptre -w 80 /dev/dvd | dd of=movie.iso
If you want to extract the chapters, you can use dvdxchap, which is part of the ogmtools package.
DVD Tracks
Every movie I’ve run into has one track specifically for the video. Using lsdvd you can find the longest track, time-length wise, and that will be the movie.
TV shows on DVD often put many episodes into one track, where one or more chapters may contain an episode. You’ll need to examine these yourself to find out where each one starts and each one ends.
Another caveat is that they are not always ordered on the track or on the DVD in the same order that shows up in the menu. The best advice when accessing tracks and titles on DVDs is to never assume anything, if you are trying to preserve order.
DVD Subtitles
Subtitles on DVDs come in two formats: VobSub and Closed Captioning. VobSub subtitles are images that are overlaid onto the picture. Closed captioning is a text format.
If you have a ripped VOB (DVD MPEG-2 video), you can extract the subtitles using a program called ccextractor. It will save the subtitles to SRT, a subtitle format that can be muxed into your final video.
Encoding DVDs
Handbrake is a very “smart” application that will make things extremely easy on you. It supports encoding using three codecs: x264, ffmpeg and theora. x264 is an actively-developed H.264 video codec, and is used professionally by many companies. It also has a lot of options that you may find useful in your encode, based on your target playback device (ipod, ipad, iphone, apple tv, htpc, computer, etc.).
Handbrake supports muxing (or putting audio and video into a wrapper format) to two containers: MP4 and Matroska. MP4 is a very popular standard used in lots of places. It’s an open-specification. Audio is usually AAC. Matroska is an open-source openly developed container format that has a standardized specification. Support for it is growing in a lot of devices. Matroska can handle multiple video streams, multiple audio streams, multiple subtitles, stores metadata, chapters and attachments. Strictly speaking, either one will work fine for most people’s needs, but for those looking for advanced usage and tagging, Matroska will fit your needs. On linux, the tools for muxing and accessing information about a Matroska file are found in the mkvtoolnix package.
Deinterlacing and Decombing
Most movies will be progressive video, meaning that each frame is one full picture. Production studios and DVD authors may have their video interlaced. Interlaced video is where half of the frame is shown in quick succession where the second half is shown. On older TVs (like the CRT tube TVs) display at a native resolution of 480i, so you won’t notice the lines. Progessive displays (computer monitors, HDTVs, etc.) will display the lines and it can be a visual annoyance.
Handbrake uses filters to convert interlaced video to progressive video, called deinterlacing. Decombing is also a feature that Handbrake supports, which is basically “smart” deinterlacing. It is safe to turn on the decombing filter to the default setting for all your encodes, and let Handbrake automatically convert your video for you. Don’t use the deinterlacing filter unless you specifically know what you are doing.
Please see 100fps.com for a quick explanation of video deinterlacing.
Other Handbrake Features
Handbrake has lots of handy features. It has support for “profiles” which is a combined set of preferences for container format, video codec, audio codecs, preferred subtitle settings, post-processing, deinterlacing, decombing, and all the H.264 settings that come with x264.
One nice thing it will do as well is auto-crop your feature film for you. This is a boon if you have a letterbox source video, where the movie itself is in widescreen, but the presentation is in fullframe.
You can also “queue” up your encodes, so Handbrake can be working on multiple files. You don’t need to wait for one to finish before assigning it it’s next task.
Handbrake is also multi-threaded when using x264 to encode your video. With a six-core desktop, I have been able to encode video using the “Normal” profile between 160 to 180 frames per second. Meaning a 25 minute video will take about 2 1/2 minutes to encode.
PHP Classes
I’ve got some small classes that I use in my shell scripts for Matroska and Handbrake (v0.95 required). You may or may not find these helpful. I should warn that these are just used on my own set of scripts, so they may or may not be very clean or can have small bugs.
References
If you want more information, here are some good places to go:
doom9
Multimedia wiki
Handbrake forums
100fps.com
Also, feel free to contact me if you have any questions, and I’ll be glad to help.