COMMON TYPES OF VIDEO CONNECTIONS BNC-­‐(Bayonet Neill–Concelman) connector is a miniature quick connect/disconnect radio frequency connector used for coaxial cable. (analog and serial digital interface (HD-­‐SDI, SDI) video signals. This connection can carry analog/composite standard definition signals (no audio) as well as HD-­‐SDI signals with audio. (Up to 300ft without having to be amplified) HDMI (High-­‐Definition Multimedia Interface) is a proprietary audio/video interface for transferring uncompressed video data and compressed or uncompressed digital audio data from an HDMI-­‐compliant source device, such as a display controller, to a compatible computer monitor, video projector, digital television, or digital audio device. HDMI is a digital replacement for analog video standards. Component video is a video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Component video can be contrasted with composite video (NTSC, PAL or SECAM) in which all the video information is combined into a single line-­‐level signal that is used in analog television. Like composite, component-­‐video cables do not carry audio and are often paired with audio cables. Composite video/RCA connector, sometimes called a phono connector or cinch connector, is a type of electrical connector commonly used to carry audio and video signals. The connectors are also sometimes casually referred to as A/V jacks. The name "RCA" derives from the Radio Corporation of America, which introduced the design by the early 1940s for internal connection of the pickup to the chassis in home radio-­‐phonograph consoles. It was originally a low-­‐cost, simple design, intended only for mating and disconnection when servicing the console. Refinement came with later designs, although they remained compatible. Video Graphics Array (VGA) refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, but through its widespread adoption has also come to mean either an Amplitude Modulated computer display standard, the 15-­‐pin D-­‐subminiature VGA connector or the 640x480 resolution itself. Digital Visual Interface (DVI) is a video display interface developed by the Digital Display Working Group (DDWG). The digital interface is used to connect a video source, such as a display controller to a display device, such as a computer monitor. It was developed with the intention of creating an industry standard for the transfer of digital video content. Video source resolution
What is resolution?
The main reason high-definition TV pictures look so much sharper and clearer than
regular TV is HDTV's higher resolution. In today's world of digital TVs, resolution is
measured in pixels, with more pixels providing higher resolution. Old-fashioned TVs had
the equivalent of around 300,000 pixels, while today's HDTVs offer one to two million
— up to six times more. All those additional pixels mean a huge jump in picture quality.
The two most common high-def video source resolutions are 720p and 1080i. All HDTV
broadcasts, including local over-the-air broadcasts, satellite and cable signals, use one of
these formats. 1080i is the most common resolution, but both formats have their benefits
and limitations:
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1080i has more lines and pixels to show more detail, so it's great for slow-moving
programs with lots of close-ups — think Law and Order or nature documentaries
on The Discovery Channel. But the "i" tells you that it's an interlaced format,
which means fewer video frames per second, so it doesn't handle fast-moving
video as well as 720p.
The "p" in 720p tells you it's a progressive-scan format, which means it presents
fast-moving action much more cleanly. It's ideal for things like sports and actionpacked video games.
What happens if your TV and video source have different resolutions?
This scenario actually happens all the time, and fortunately with today's HDTVs, you
don't really need to worry about it. Whether the resolution of your video source material
is low (VHS), medium (DVD), or high (HDTV), a fixed-pixel TV will always
automatically convert or scale the video signal to fit the screen's native resolution.
Scaling lower-quality signals to fit a TV's higher-resolution screen is often called
upconversion. Upconversion works great with a good source like DVD, but it can't make
snowy analog antenna reception or a noisy cable picture look flawlessly crisp and clear.
Similarly, if the incoming source has more pixels than the screen's native resolution, the
video signal has to be "downconverted." It's like trying to pour 10 pounds of sugar into a
5-pound bag: you have to throw away some detail to fit the image on the screen. That's
one of the reasons 1080p TVs are so popular — they can display every pixel of every
available high-def resolution, so they never have to throw any detail out. But if you don't
get a 1080p TV, don't worry — downconverted video can still look great. The best
example is 1080i HD broadcasts that are downconverted to be viewed on 768p TVs.
Chart showing aspect ratio (16 x 9 or 4 x 3) in relation to screen size Width Height Pixel aspect ratio
Screen aspect
ratio
Description
320
240
1:1
4:3
Used for web distribution or offline video editing.
640
480
1:1
4:3
An early standard for analog-to-digital video editing, and an ATSC
video specification.
720
480
Height greater than
4:3
width
NTSC DV and DVD image dimensions. Also part of the ATSC video
specification.
1280 720
1:1
16:9
An HD video format, capable of higher frame rates in exchange for
smaller image dimensions.
1920 1080
1:1
16:9
An HD video format with very high resolution.