quikchai.com

My elections

Notasinc.com

Nyc-it.com

Orderatease.com

Website design

Parkway village

Portablesymas.com

Pre columbian cultures/a>

Pre columbian handicrafts

Quickchai.com
quikchai.com Aspect ratio Video quality Video compression method Video Formats Video Display Standards Video Connection Standards Digital Tape Formats

Video Connection Standards

Composite video

Composite video is the format of an analog television (picture only) signal before it is combined with a sound signal and modulated onto an RF carrier. It is usually in a standard format such as NTSC, PAL, or SECAM. It is a composite of three source signals called Y, U and V (together referrered to as YUV) with sync pulses. Y represents the brightness or luminance of the picture and includes synchronizing pulses, so that by itself it could be displayed as a monochrome picture. U and V between them carry the colour information. They are first mixed with two orthogonal phases of a colour carrier signal to form a signal called the chrominance. Y and UV are then added together. Since Y is a baseband signal and UV has been mixed with a carrier, this addition is equivalent to frequency-division multiplexing.
Composite video cannot easily be directed to any broadcast channel simply by modulating the proper RF carrier frequency with it. Most analogue home video equipment records a signal in (roughly) composite format: Laserdiscs store a true composite signal, while VHS tapes use a slightly modified composite signal. These devices then give the user the option of outputting the raw signal, or modulating it on to a VHF or UHF frequency to appear on a selected TV channel. In typical home applications, the composite video signal is typically connected using an RCA jack, normally yellow (often accompanied with red and white for right and left audio channels respectively). BNC connectors and higher quality co-axial cable are often used in more professional applications.
In Europe, SCART connections are often used instead of RCA jacks — though SCART can also carry far superior RGB component video signals (and to a lesser extent, S-Video), so where available, RGB is used instead of composite video with computers, video game consoles, and DVD players.

Some devices that connect to a TV, such as videogame consoles (and the ubiquitous home computers of the 1980s), naturally output a composite signal. This may then be converted to RF with an external box known as an RF modulator that generates the proper carrier (often for channel 3 or 4 in North America). The RF modulator is preferably left outside the console so the RF doesn't interfere with the components inside the machine. VCRs and similar devices already have to deal with RF signals in their tuners, so the modulator is located inside the box. Also, most early home computers usually employed an internal RF modulator.
The process of modulating RF with the original video signal, and then demodulating the original signal again in the TV, introduces several losses into the signal. RF is also "noisy" because of all of the video and radio signals already being broadcast, so this conversion also typically adds noise or interference to the signal as well. For these reasons, it is typically best to use composite connections instead of RF connections if possible. Almost all modern video equipment has composite connectors, so this typically isn't a problem.
However, just as the modulation and demodulation of RF loses quality, the mixing of the various signals into the original composite signal does the same. This has led to a proliferation of systems such as S-Video and component video to separate out one or more of the mixed signals.

Composite video is often designated by the CVBS acronym, meaning either "Color, Video, Blank and Sync", "Composite Video Baseband Signal", "Composite Video Burst Signal", or "Composite Video with Burst and Sync".

Component video

Component video is a type of analog video information that is transmitted or stored as two or more separate signals. Component video can be contrasted with composite video (such as NTSC or PAL) in which all the video information is combined into a single signal such as a TV broadcast. However, component video cables are gradually being replaced by the higher quality DVI and HDMI cables

Analog component video

Analog video signals (also called components) must provide red, green and blue signals to create a television image. The simplest type, RGB, consists of the three discrete red, green and blue signals sent down three coaxial cables. There are a number of variant schemes which vary according to how synchronization is handled. If a synchronization signal is sent on the green channel, it is called sync-on-green. Some schemes use a separate sync channel, for instance the European SCART connection scheme in which the video signal occupies four (R,G,B + sync) of the 21 pins in the interface. SVGA, another RGB scheme, is used worldwide for computer monitors (this is sometimes known as RGBHV, as the horizontal and vertical synchronization pulses are sent on separate lines).

An alternative type of componentization does not use R,G,B components but rather a colorless component, termed luminance combined with one or more color-carrying components, termed chrominance, that give only color information. Mulitiple chrominance channels allow for more precision and speed in mapping the RGB colour space. This componentization scheme is a linear transformation of the sRGB color space. This type of signal is usually what is intended when people talk of component video today. Variants of this format include YUV, YCbCr, YPbPr and YIQ commonly used in video systems.

In component video systems, additional synchronization signals may need to be sent along with the images. The synchronization signals are commonly transmitted on one or two separate wires, or embedded in the blanking period of one or all of the components. In computing, the common standard is for two extra wires to carry the horizontal and vertical components ('separate syncs'), whereas in video applications it is more usual to embed the sync signal in the Y component ('sync on luminance').
S-Video is another type of component video signal, because the luminance and chrominance signals are transmitted on separate wires. This connection type, however, cannot produce high definition or digital-quality pictures (pictures with more than 480 interlaced lines of video for NTSC or more than 576 lines of interlaced video for PAL). Component video is capable of producing signals such as 480p, 720p, 1080i and 1080p, but digital connections such as DVI (video only) and HDMI (which can also include up to 8 channels of audio) give better results at the higher resolutions (up to 1080p).

Examples of international component video standards are:
RS-170 RGB (525 lines, based on NTSC timings, now EIA/TIA-343)
RS-343 RGB (525, 625 or 875 lines)
STANAG 3350 Analogue Video Standard (NATO military version of RS-343 RGB)

Digital component video

The digital component video is sometimes referred to as 4:2:2. This means that for every 4 pixels of luminance (Y) information, only 2 pixels of Pb (Blue Difference), and 2 pixels of Pr (Red difference) are encoded. This is the scheme used for the DVD format. The numbers also represent the relative number of bits (but not the actual number) used to carry the three pieces of information at each pixel. The color information is spread across the pixels it represents.

Another scheme encountered will be 4:1:1. This is the scheme used on the NTSC version of the DV (and hence miniDV) tape formats for camcorder use. In this case for every 4 pixels of luminance, only 1 pixel of the Pb and Pr difference information is encoded for each line.
To provide apparent confusion, the PAL version of the DV and miniDV tape format use 4:2:0 which would appear to suggest the absence of the Pr signal altogether. In fact, the system takes advantage of features of the PAL color system, and encodes 2 pixels of Pb color difference for every 4 luminance pixels on odd lines only. On even lines, 2 pixels of Pr color difference are encoded for every 4 luminance pixels. In each case the missing information is recovered from the previous line (and is thus closer to the French SECAM system than PAL). This doubles the horizontal resolution but halves the vertical resolution. This is acceptable, because the PAL analogue color system does in fact have half the vertical resolution of the NTSC system.
 

Nofeerentals.com No fee one bedroom,two bedroom rental apartments Astoria, Queens NY
Nofeerentals.com no fee rental apartments in Astoria Queens NY one bedroom, two bedroom, three bedroom , four bedroom rental apts
http://www.nofeerentals.com/new-york/queens/astoria.asp

Notasinc.com Leather sculptures Handcrafted handmade faces and torsos, Colombian artist
Leather sculptures handcrafted faces and torsos unique items for holiday, handmade exclusive gifts for any occasion
http://www.notasinc.com/leather_sculptures.htm

Jewelheaven.com Ruby Rings
Ruby Ring is a band worn as a type of ornamental jewelry around a finger. Ruby is a red gem stone that varies from light pink to blood red, a variety of mineral corundum. Ruby had magnificent color, excellent hardness and used to make ruby rings.
http://www.jewelheaven.com/Ruby-Rings.asp

Lansend.com: Microsoft Certified Computer consultants in New York, NY
Microsoft Certified Computer consultants providing computer and network consulting services in New York ,NY Manhattan Queens, Lan Wan Networking VPN.
http://www.lansend.com

Washable microfiber futon cover suede futon covers bone color cheap futon cover
bone suede  microfiber futon cover similar to a real suede futon cover polyester easy care microfiber futon cover is machine washable suede futon cover
http://www.futonstogo.com/details-of-product/futon-cover-suede-bone-suede-solid.asp

 
quikchai.com Aspect ratio Video quality Video compression method Video Formats Video Display Standards Video Connection Standards Digital Tape Formats