HDCP, HDMI, DVI, 1080p, And Other Definitions
This is the latest in a series of Avivo vs. PureVideo articles, so some of the terms might justify re-explanation for those who are joining us fresh. For detailed definitions, we encourage the reader to check the other article links from the first page of this review.
High-Definition Content Protection is an encryption scheme for high-definition video to prevent the video data stream from being copied between the digital video output on your computer (DVI or HDMI) and your monitor. For it to work, both the graphics card and the monitor must be “HDCP-Compliant.” If both pieces are not compliant, the system will refuse to play the video.
The High Definition Multimedia Interface is a digital audio/video output option, used mostly with high-definition televisions. HDMI has the distinction of being able to carry both digital audio and digital video information at the same time. If the hardware is compliant it can carry an HDCP signal.
The Digital Video Interface is another digital video output option, used mostly with computer monitors. It is only designed to carry video information, but does not work for audio. If the hardware is compliant, it can also carry an HDCP signal.
This refers to the horizontal resolution of high-definition content, in this case 1920 vertical lines by 1080 horizontal lines. The "p" means that the signal is "progressive," which indicates that all 1080 lines are broadcast at once. For reference, an "i" instead of a "p" means that the signal is "interlaced" and only shows half of the total horizontal lines of resolution at one time.
This also refers to the horizontal resolution of the high-definition video signal; in this case the signal is 1280x720.
Linear Pulse Code Modulation is an encoding digital audio method.
Video Codecs: H.264, VC-1, And MPEG2
The term "codec" stands for "COmpression-DECompression." As high-definition video includes too much information to broadcast without compressing it, a codec must be used to fit movies onto a Blu-ray disk. There are three video codecs used in Blu-ray disks today: H.264, VC-1 and MPEG2.H.264 is the newest and most demanding codec to play back, but offers the best compression. The VC-1 and MPEG2 codecs are a lot easier for the hardware to decompress, so they require less processing power, but they also take up more space on the disk.
HDMI Outputs And Audio Controllers
Since HDMI is capable of carrying both video and audio information through a single cable, it has become important for video solutions to carry audio as well.
While the Radeon 3000-series pioneered an integrated audio processor for use with the HDMI output, they are limited to compressed 5.1 channel sound (like Regular Dolby Digital or DTS) or uncompressed 2-channel LPCM. These same limitations are found on the 780G chipset with the integrated Radeon 3200.
Nvidia upped the ante with its MCP78S chipset/GeForce 8200 by enabling the platform to support eight-channel uncompressed LCMP audio. The board fully supports TrueHD and DTS-HD uncompressed 7.1 surround sound as long as it’s decoded in software like PowerDVD. Because of this, audiophiles may find the GeForce board preferential, although some issues did occur during video testing that may detract from this appeal. More about that a bit later.
On a side note, the situation is reversed in the discrete video card market, where AMD’s 4000-series Radeons support eight-channel sound over HDMI, but the GeForce GTX 280 and 260 do not.