Hardware Reference
In-Depth Information
•
Region Code 8
—International venues including aircraft and cruise ships.
•
Region Code All
—Has all flags set, allowing the disc to be played in any region or player.
Sometimes called Region Code 0.
The region code is embedded in the hardware of DVD video players. Most players are preset for a
specific region and can't be changed. Some companies that sell the players modify them to play discs
from all regions; these are called
region-free
or
code-free
players. Some newer discs have an added
region code enhancement (RCE) function that checks to see whether the player is configured for
multiple or all regions and then, if it is, refuses to play. Most newer region-free modified players
know how to query the disc first to circumvent this check as well.
DVD-ROM drives used in PCs originally did not have RPC in the hardware, placing that
responsibility instead on the software used to play DVD video discs on the PC. The player software
would usually lock the region code to the first disc that was played and then from that point on, play
only discs from that region. Reinstalling the software enabled the region code to be reset, and
numerous patches were posted on websites to enable resetting the region code even without
reinstalling the software. Because of the relative ease of defeating the region-coding restrictions with
DVD-ROM drives, starting on January 1, 2000, all DVD-ROM and rewritable DVD drives were
required to have RPC-II, which embeds the region coding directly into the drive.
RPC-II (or RPC-2) places the region lock in the drive and not in the playing or MPEG-2 decoding
software. You can set the region code in RPC-II drives up to five times total, which basically means
you can change it up to four times after the initial setting. Usually, the change can be made via the
player software you are using, or you can download region-change software from the drive
manufacturer. Upon making the fourth change (which is the fifth setting), the drive is locked on the last
region set.
Region Codes Used by BD
A different region code scheme that divides the world into three regions is used by BD:
• Region A includes North America, Central America, South America, Korea, Japan, and South
East Asia.
• Region B includes Europe, the Middle East, Africa, Australia, and New Zealand.
• Region C includes Russia, India, China, and the rest of the world.
A BD without a region code can be played by players with any region code.
Optical Drive Performance Specifications
Many factors in a drive can affect performance, and several specifications are involved. Typical
performance figures published by manufacturers are the data transfer rate, the access time, the internal
cache or buffers (if any), and the interface the drive uses. This section examines these specifications.
CD Data Transfer Rate
The data transfer rate for a CD drive tells you how quickly the drive can read from the disc and
transfer to the host computer. Normally, transfer rates indicate the drive's capability for reading
large, sequential streams of data.
Transfer speed is measured two ways. The one most commonly quoted with optical drives is the “x”
speed, which is defined as a multiple of the particular standard base rate. For example, CD drives
