DVI:

DVI (Digital Visual Interface) input is the digital standard created by the Digital Display Working Group (DDWG).  This type of connection theoretically improves the quality of display compared to VGA thanks to a separation of colors for each pixel and entirely digital transmission (no conversion of the signal).  Be careful, however, there are several types of DVI plugs :

- DVI-A : the ’’A’’ actually stands for ‘’analog’’! This means that if your screen has a DVI input, the signal isn’t necessarily digital.

- DVI-D : the signal is digital, however, in its native format with no double analog/digital – digital/analog conversion.

- DVI-I : DVI-I combines DVI-D and DVI-A and there is no conversion.  The two signals are transmitted via the 29 available pins.

Following the example of HDMI (below), DVI digital connectors can fall under the HDCP protection standard.  As you may have noticed, they aren’t always digital and so special attention should be given to the connectivity of the product you are about to buy.  DVI can also be used in dual link by connecting two DVI plugs via a dual link connector to the transmission source.  This process is used for very high resolution screens.

HDMI:

HDMI (High-Definition Multimedia Interface) is a standard for the transmission of video and audio digital signals created by a consortium composed of Hitachi, Matsushita, Philips, Silicon Image, Sony, Thomson and Toshiba.  Its goal is to replace the input on different general public devices formerly found on home DVD players, monitors, VCRs, satellite receivers, etc.  This input is in second place behind DVI because its maximum resolution is limited and insufficient even for certain rare ultra-high resolution computer monitors (for example, the 30 inch Apple and Dell).  This limitation will be overcome because a second version, in addition to the current HDMI-A, will make an appearance under the name, HDMI-B (for resolutions superior to 1080p).

3 versions of HDMI-A exist: 1.0, 1.1 and 1.2. Officially, only the version 1.3 will support 1080p at 50/60 Hz.   Currently, all HD Ready or Full HD panels have HDMI version 1.0, 1.1 or 1.2 .   Version 1.0 compatibility with 1080p @ 50/60 Hz is planned but optional and it’s the manufacturer who decides to integrate it or not.

- HDMI A : the format currently found on all projectors and televisions equipped with an HDMI connection.

- HDMI B : larger than HDMI A, it is destined to transmit very high definition data requiring a dual link configuration.

HDMI input is subject to the HDCP standard but not in every case.  Like with DVI connections, verify if your product is HDCP (or HD Ready) compatible.

VGA:

VGA (Video Graphics Array) is a computer display standard launched in 1987 by IBM.  Connection with your PC monitor or projector is done via a SUB-D High Density 15 pin plug.  The transmitted signal is analog and HD compatible like DVI and HDMI.  However, it isn’t HDCP compatible.







YPrPb, YUV, YCrCb (component video) :

Signals conducted by YPrPb are analog.  The three cables used for this connection have a higher quality than the single composite cable used on video equipment. Brightness and the component colors are transmitted separately.  The YPrPb signal is derived from the RGB which is captured by a digital camera, for example, then converted into brightness (Y for luma) + two signals for the differences between the color and brightness (Blue-Y=Pb and Red-Y= Pr).  Like VGA, this input isn’t compatible with the HDCP protection norm.

What is the relationship between YUV, YPrPb and YCrCb? First of all, YUV and YPrPb are analog and YCrCb is digital.  However, they all transmit 3 signals. Y always stands for brightness and then they differ on the modulation of Pr and Pb, Cr and Cb or U and V.   In other words, the calculation method and variables used in the calculation of color differences are not the same.

Their applications are also different.  YUV was created back in the day for analog video, YPbPr was intended for analog and YCbCr is for digital video.

SCART:

SCART (Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs) is a French standard created in 1978.   It can carry several types of signals in addition to sound  (composite, S-Video and RGB) depending on the internal cabling of the connection and the devices it relays.







S-Video:

S-Video (from Super Video) is an analog signal which is divided into two components ; luminance (Y) and modulated chrominance (C).  The signal sent to a connector produces sharper images than RCA cables because of this separation of  Y and C.







Composite video:

This has the lowest quality of this list and is composed of a combined red, green and blue signal (and sometimes an additional audio signal).  The image is significantly degraded and can be affected by "snow", a lack of sharpness, and shimmering can be accentuated.