Difference between revisions of "Standard Video Device Connector"

Revision as of 22:00, 25 December 2010

Video connectors exist on television video equipment, and now on personal computers and other types of electronics. Just a couple decades ago the world of video connectors was extremely simple. Today, through a combination of factors including an overall lack of industry standardization, competing companies, corporate greed, draconian anti copy laws, anti copy technologies, and a general push for technology that not all consumers even want, we now have a dizzying array of different video connector types.

RF 75 Ohm

(analog, audio and video, lowest resolution video quality)

Composite / RCA

(analog, video only, low resolution video quality)

This is superior to 75 Ohm RF. This type of connection combines chrominance and luminance information, sending it along a single cable. Though capable of delivering a high-quality picture, composite video is not as accurate as either S-video or component video, both of which provide separate paths for chrominance and luminance.

S-Video

(analog, video only, medium resolution good video quality)

S-video inputs and outputs use a round, 4-pin jack. The "S" in S-video stands for "separate." S-video connections transmit the chrominance (color) and luminance (brightness) portions of a video signal along different paths, allowing them to be processed separately. It provides a sharper picture than composite video.

Component Video

(analog, video only, better "DVD" video quality)

Component video consists of three analog signals, luminance, blue color difference, and red color difference. The color difference signals are mathematical derivatives of the RGB signal. Component video is superior to composite video and S-Video by providing greater signal clarity, resulting in better picture quality.

YPbPr analog component video is the most common type and works by separating the components of a video signal so that they do not interfere with each other. Each component cable in the set is independently shielded and component video connections yield even better performance than S-video by further dividing the chrominance portion of the video signal.

A drawback to component video is the number of cables involved for consumer electronic connections. Consider the 3 component video connection cables, and 2 additional for stereo sound, the consumer has to connect 5 total cables from a video source to a television.

The Nintendo Wii utilizes Component video.

PC VGA

(analog, video only, very high video quality)

Used primarily for computer monitors and LCD flat-panel screens that display images from both traditional audio/video and computer video sources. It uses a 15-pin connector to carry packets of video information in a different format than that coming from other sources such as DVD players or cable boxes.

DVI - Digital Video Interface

DVI is a multi-pin connection used for passing standard-definition and high-definition digital video signals.

HDMI - High-Definition Multimedia Interface

(digital, audio and video, highest available video quality)

HDMI (High-Definition Multimedia Interface) is an audio/video interface for uncompressed, all-digital, connectivity that delivers true HD quality for consumer electronics. With 19 wires wrapped in a single cable that resembles a fat USB wire, HDMI is able to carry a bandwidth of 5 Gbps (gigabits per second). This is more than twice the bandwidth needed to transmit multi-channel audio and video.

Wikipedia describes HDMI as "compact," however, with 19 wires wrapped in a single cord it is actually quite heavy and stiff, being somewhat difficult to work with in "in wall" applications, and limited in transmission range. The concept is primarily for simplicity so the consumer only has one cable to connect for all video color bands as well as hifi audio.

Unlike PC VGA, HDMI is all digital. HDMI has superior video quality when compared to Component Video, S-Video, and Composit. HDMI includes the audio as well as video, unlike the aforementioned video cable types.

A newer technology called HDBaseT looks to replace HDMI, which will be a welcome improvement.

RGB Video

The RGB (D-sub 15-pin) jack is found on some HDTV-ready TVs and HDTV tuner boxes, RGB connections are used for transferring video signals, including high-definition content. As implied by its name, RGB sends the red, green, and blue components of the video signal along separate paths.

HDBaseT

This one is based on the Cat 5e/6 network cables, commonly referred to as “ethernet cables” and will replace HDMI. HDBaseT is superior to HDMI for many reasons including it uses a standard cable that is more flexible and easier to work with, has much greater range, and the cable is far less expensive than HDMI. It supports cable lengths up to 328 feet. The cable can pass HD and 3-D video signals, as well as data through an integrated 100MBit Ethernet connection.

• Article: Goodbye HDMI, Hello HDBaseT