mplayer and broken DVDs
If you know me, you are well aware of my love for Linux and Open Source software. Unfortunately, the philosophy and goals of such software is in direct conflict with the MPAA and RIAA (referred to henceforth as MAFIAA). Thus, there is a continuing battle between people, like myself, who want to play their legally-bought DVDs on a Linux machine and the MAFIAA wishing to control that freedom.
In order to try and control how and where people can play their DVDs, an encryption scheme called "Content-Scrambling System" was implemented. This was a short-lived achievement, since a trio of programmers were able to develop a program called DeCSS which stripped this protection and allowed compete access to the disk. (Wikipedia has the whole story here.) The MAFIAA was unable to fix the problem, since it would have meant recalling/replacing all existing DVD players or making new DVDs incompatible with the existing players. It's bad for them, but good for us. Now days, Linux users can play DVDs using the libdvdcss library and all is well in the world -- until recently.
I use mplayer for playing my DVDs. It works great, has a minimal interface, and can play just about anything I throw at it. However, some recent DVDs I have bought refuse to play. It seems that they purposely insert garbage information at the beginning of the disc which prevents libdvdcss from properly decoding the video stream. After doing some research, I found a solution which still allows me to play these DVDs: you need to tell mplayer to skip the first few megabytes of the stream before beginning to decode the video. Here is the command which I use:
mplayer -sb 2500000 dvd://1
The magic is the "-sb" (seek to byte) option; the number 2500000 is somewhat arbitrary, and was found through trial and error.
Here is a list of DVDs which I have experienced this problem with:
The Dark Knight (Region 1, 2008, Wide-screen) The Muppet Show: Complete Third Season (Region 1; 2008) Star Trek (Region 1, 2009, Wide-screen, Two disc digital copy edition)
Finally, a closing thought. I have not bought any Blu-ray discs (nor do I plan to) until I can play them on my Linux system. The MAFIAA learned their lesson with DVDs, and the protection on the new discs is much better than before. However, I refuse to buy multimedia from companies unless I can completely control what I do with it -- just like a consumer can do with anything else they purchase.