Region Coding is a copy protection/sales protection scheme created by the DVD Forum to prevent DVD-Video discs from being sold in markets other than those they were intended for. The concept is that movies typically are released on DVD in the US around the same the same film hits the big screen for the first time in other countries, such as England, so without Region Codes people could buy the movie on DVD and never pay top dollar to see it in a cinema. This is all well-documented as part of the DVD spec. Incidentally, the DVD Forum is made up of the major manufacturers and all the major film studios.

VLC is a video playback software. VLC stands for Video Lan Client. It is cross-platform and free and can be found here:

www.videolan.org

MacTheRipper is an application that allows a user to extract the CSS-encrypted contents of a DVD. You can find it here:

macupdate.com/info.php/id/14414

RPC stands for Region Protection Code. When DVD-ROM drives first started shipping about 6 years ago, manufacturers (and the DVD Forum) recognized that it would be silly to make drives for each region, so RPC was created to give manufacturers rules by which they could program the Region Codes for a drive using the firmware. RPC-1, which was the initial version, would allow 5 region code changes, that way consumers could set their Region Code the first time they tried to play a DVD in their new DVD-ROM. After 5 changes, the Region Code was supposed to be locked in, however a backdoor was left in place so manufacturers could allow a consumer another 5 changes, since they might have made a mistake.

Of course, hackers quickly discovered the backdoor and realized there was no limitation on exploiting it. When the DVD Forum found out that people were exploiting the unlimited manufacturer resets, they required manufacturers to limit the number of resets to 4 MAX. So, for the past 5 years (or so), manufacturers have been shipping drives that can only allow 4 maximum manufacturer resets, which is referred to as RPC-2. That means a total of 20 changes total. There is no circumventing this limitation.

Naturally, though, it doesn't end there. There are several really talented hackers who have discovered that the difference between RPC-1 and RPC-2 drives is usually a simply modification to the firmware, which is the onboard software that runs the drive itself. So, many drives have been hacked to reprogram them to be RPC-1, even though they originally shipped as RPC-2.

Hacking drives to RPC-1 went on unabated for quite some time, but many manufacturers have taken steps to make reprogramming the drives incredibly difficult. For example, the Matshita UJ-815 drive was one of the first to store its firmware onboard in an encrypted manor. Before that, a simple software tool could extract the existing firmware so a hacker could modify it. With encrypted drives, obtaining the firmware to hack is much trickier. Typically it means waiting for the company that OEM'd the drive (like Apple) to ship a firmware updater. Then, the firmware is available to inspect and can sometimes be hacked.

If your DVD unit doesn't have any RPC-1 hacks, you don't have a whole lot of options. VLC tends to play DVDs regardless of the Region Code, however some newer drives will refuse to even read the disc if the Region Code doesn't match. If VLC works for you, then you can play the movies. If not, you can try MacTheRipper to copy the DVD to your hard drive. If neither of those work, you are essentially out of options.

Some good resources:

forum.rpc1.org/dl_all.php
www.powerbook-fr.com/dossier...e30.html