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The FBAS composite (color image blanking synchronous) signal is the standard transmission signal in the video field which is understood by all devices. Unfortunately, it is also the signal with the poorest quality, because here the brightness signal Y (luminance) and the color signal C (chrominance) together with the synchronization signal are transmitted interlaced over one line.

Separating the two signals in the receiver leads to more or less pronounced cross-color or cross-luminance effects, depending on the quality of the comb filter used. In this case, a small checkered jacket shimmers in all colors.

Note: The FBAS composite signal is output either via a yellow Cinch/RCA socket or via the SCART connection socket.

S-Video – Y/C

An S-Video Y/C signal is not a broadcastable format because the brightness signal Y (Luminance) and the color signal C (Chrominance) are transmitted separately over two cables. Because the signals do not have to be separated from each other in the receiver, the cross-color or cross-luminance effects that occur with FBAS transmission do not occur.
This transmission system is often wrongly called S-VHS transmission. S-VHS is a similar technique which records the brightness signal Y (Luminance) and the color signal C (Chrominance) separately in S-VHS video recorders, but has nothing to do with the transmission of video data.

Note: The S-Video Y/C signal is output either via an S-Video Y/C – Hosiden socket or via the SCART connection socket.

RGB

The RGB (Red Green Blue) signal is not a broadcastable format, because here the colors are separated according to the three basic colors and 3 cables are transmitted. The Syncron signal can be transmitted in different ways. Mostly the FBAS signal is used for this, which is also transmitted with a SCART connection, this is then called sRGB (occasionally also called RGBS or RGBY). The Syncron signal can also be on the green color channel, this is then called RGsB. Or the Syncron signals are transmitted completely separately on separate lines as H-Sync (Horizontal Sync) and V-Sync (Vertical Sync), this is then called RGB HV.A YUV component connector may also consist of Red, Green, Blue RCA or BNC connectors, and could be mistaken for an RGB connector. These should not be labeled with RGB, but with Y, U (Cb/Pb) and V (Cr/Pr).
To make the confusion complete, there are also constructions where the RGB pins are assigned with the YUV signals. So there are devices that output YUV signals via a SCART socket. In this case the Y is on RGB green, the U (Cb/Pb) on RGB red and the V (Cr/Pr) on RGB blue.
Note: The RGB signal is output via the SCART connector, or in very rare cases for projector control via 5 Cinch/RCA or BNC sockets as RGB HV.

The brightness portion Y (Luminance) is won from the RGB color space thereby as follows.

• For the Y brightness signal : 0.3 * Red + 0.59 * Green + 0.11 * Blue

YUV – Component

The YUV – YCbCr component (Y = brightness, U and V are the color difference signals) signal is also not a broadcast-capable format, because here too the information is transmitted via three cables. Here the brightness (Luminance) and the Sync on Y and the two difference signals U (Cb/Pb) and V (Cr/Pr) are transmitted separately. Since the color information on the DVD itself is in this color format, this type of transmission naturally offers the optimum in picture quality.The proportions are as follows:

• For the Y brightness signal : 0.3 * Red + 0.59 * Green + 0.11 * Blue
• For the U (Cb/Pb) Red differential signal : – 0.17 * Red – 0.33 * Green + 0.5 * Blue
• For the V (Cr/Pr) Blue difference signal : 0.5 * Red – 0.42 * Green – 0.081 * Blue

If a SCART RGB socket is also used for YUV signals, then the Y is on RGB green, the U (Cb/Pb) is on RGB red and the V (Cr/Pr) signal is on RGB blue.
Note: The YUV component signal is output via three Cinch/RCA or BNC sockets which are then labeled Y, U (Cb/Pb) and V (Cr/Pr). Evtl. five sockets are also used, if the Sync signal HSync and VSync are led separately. Otherwise the sync signals are included in the Y signal.

Connection of the DVD player

Basic

For the picture a DVD player has at least one, some even two SCART sockets, at which the appropriate picture signals in the different transmission standards FBAS – Composite or S-Video – Y/C or RGB are present.In addition, some players also have separate jacks for FBAS – Composite (yellow RCA jack) and/or for S-Video – Y/C (round 4 pin Hosiden jack). Some few have in addition still another connection for YUV – Component signals (3 Cinch or BNC beeches) and/or a VGA socket for progressive Scan picture signals.

The setup settings for the image signal (FBAS – Composite, S-Video – Y/C or RGB) of the DVD player always refer to the SCART socket only because all three signal forms cause double assignments in the SCART cable and therefore only one signal form can be transmitted at a time.
It is important that the FBAS – Composite and/or S-Video – Y/C sockets (if present) always receive the respective picture signal, regardless of what is defined in the setup of the DVD player.

The following points should always be observed:

• Before activating a signal form other than composite, make sure that the DVD player and the TV set both support this other signal form.
• Not every DVD player can output S-Video Y/C and/or RGB picture signals.
• Not every TV set can process S-Video – Y/C and/or RGB picture signals.
• When using a SCART cable, the signal form to be transmitted via the SCART cable must be set in the setup of the DVD player.
• Via the setup in the TV set, the signal form must be selected which is present at the AV SCART input socket.
• The selected signal form must be identical in both the DVD player and the TV set.
• For the S-Video – Y/C or RGB signal form, a fully wired SCART cable must be used.
• If the video signals are routed via an AV receiver, then no signal conversion takes place with most devices. Means, an input signal at the FBAS – Composite comes out only at the FBAS – Composite output, but not at the S-Video – Y/C output. Possibly. Therefore you have to connect the AV receiver with FBAS – Composite and S-Video – Y/C cables to the display device
• Some devices like e.g. DenonAV receivers can also use e.g. perform a conversion from FBAS – Composite to S-Video – Y/C and even YUV – Component. This simplifies the cabling with a projector immensely and you do not need expensive signal converters.

Whether for the picture transmission instead of a SCART connection a sperates FBAS – Composite Cinch/RCA or S-Video Y/C Hosiden cable is used, has no influence on the picture quality, only the selected signal form is crucial for the picture quality. Exactly the same signals are transmitted via a SCART connection as are present at the separate FBAS – Composite or S-Video Y/C sockets (if available). The only advantage of a SCART connection is that the analog audio signals (but no digital audio signals) are also transmitted when the TV set is used as a playback device for the audio signals. Otherwise, the analog audio signals would have to be connected via extra RCA connections.

FBAS – Composite

To the signal forms in detail, how they are to be used and which advantages and disadvantages they have:

The picture of a DVD player can be seen in the standard setting on every TV set, because it is output as FBAS composite (color picture blanking synchronous) picture signal via a Cinch/RCA socket. This picture signal standard is also used by VHS recorders or all other devices that are connected via audio/video cable. It is the simplest, but unfortunately also the worst way of transmitting an image signal, because only one line is used for brightness, color and sync signals. The signals are mixed together in the DVD player and must be extracted again from the signal mix in the TV set by means of complex comb filters. Unfortunately, the process is not complete, so that flickering is noticeable, especially with critical picture elements, such as fine karaoke patterns in clothing. This effect is also called Cross Color or Cross Luminance.

The FBAS Composite signal can be transmitted either via a FBAS Composite – Cinch/RCA cable or via a SCART cable.

S-Video – Y/C

A large increase in picture quality is already achieved when using the S-Video or Y/C (Y = brightness, C = color) picture signal. The brightness signal (luminance) and the color signal (chrominance) are transmitted separately via two lines. The sync signals are mixed with the brightness signal. The advantage of this signal form is that the color signal does not have to be extracted in the TV set by means of a complex comb filter and therefore the color flicker typical of FBAS composite does not occur.

For a lot of confusion a strange phenomenon causes again and again, that a S-Video Y/C picture signal is played back only in black/white. The reason for this is relatively simple, if you know how an S-Video image signal is transmitted. The brightness signal (luminance) is transmitted via the FBAS composite line of the SCART cable. The color signal (chrominance) is transmitted over the line of the SCART cable on which the RGB red signal is otherwise located. If no fully wired SCART cable is used, the color information does not arrive at the TV set at all. Thus only the brightness signal is displayed, which is present on the FBAS composite line, which results only in a black/white picture.

Another reason for the black/white picture could be that the DVD player has not been switched to SCART S-Video Y/C output, that the TV set is not S-Video Y/C capable, that the selected AV SCART input is not S-Video Y/C capable, or that the AV SCART input of the TV set has not yet been switched to the S-Video Y/C picture signal. This must be done manually with almost all TV sets, because there is no switching voltage for it and the S-Video Y/C picture signal cannot be recognized automatically.

The S-Video Y/C signal can be transmitted either via an S-Video Y/C – Hosiden cable or via a fully wired SCART cable.

Attention: When using a SCART connection, it is mandatory to use a fully wired SCART cable.

RGB

A further increase in picture quality is achieved with an RGB (red, green, blue) picture signal. The picture signal is always transmitted via a SCART connection. Here the three basic colors red, green, blue are transmitted over separate lines and can be processed so directly by the TV set.
Since a synchronous signal is needed here as well, it is transmitted via the line on which the FBAS composite signal is otherwise present. Theoretically, the synchronization impluse would be fully sufficient to display an RGB image. Many DVD players still transmit a full FBAS composite signal on this line, which leads to a lot of confusion. The TV set, although it has not been switched to the RGB image signal, continues to display an image. This is then the picture which is transmitted over the FBAS Compoiste line. Only when the TV device switches over automatically either manually via the setup of the TV device, where the input signal must be selected at the AV SCART socket, or via a switching voltage, which is also transmitted via the SCART cable, the TV device sees an RGB picture signal.

Unfortunately, when using a RGB image signal, the image may be shifted horizontally. The reason for this is that the sync signals are often not correct and the image is therefore shifted to the left. Whether this can be compensated, depends on the DVD player and / or the TV set. Furthermore a RGB picture can be too bright or too dark. Again, it depends on the DVD player and/or TV set whether this can be corrected.

Some projectors also have a VGA socket, which is usually used for an RGB signal. Unfortunately it is very difficult to find suitable adapters from SCART to VGA. For an sRGB connection to the projector at least 4 (maximum 5) high quality 75 Ohm video cables (RGB + FBAS) are required as well as possibly a cable for the projector. corresponding Cinch/RCA or BNC to VGA adapter needed. However, it becomes very difficult if the projector has separate sync inputs for HSync and VSync, i.e. RGB HV, or expects the sync on a color line (usually green), i.e. RGsB. Possibly. you can use a Sync Stripper to extract the desired signal resp. generate.

In addition there are for Progressive Scan pictures as well as a Wide RGB connection possibility. From the specification, this is a normal RGB connector, but can also transmit 32kHz video signals, as they are required for full images. For Progressive Scan playback one needs however compellingly appropriate playback devices. Normal TVs or projectors cannot process such signals.

Note: In contrast to the FBAS Composite or S-Video picture signals, which both transmit the color signal with either a PAL or NTSC modulated color carrier, the RGB picture signal does not contain a color carrier. Therefore the RGB video signal can be. can be used if an NTSC DVD is played back on one of the DVD players, which then generates an NTSC picture signal, but no multinorm TV set is available and the DVD player cannot be switched to the PAL-60 mixed signal understood by almost all TV sets.

Attention: An RGB picture signal can only be transmitted via a fully wired SCART cable.

YUV – Component

The YUV – Component (Y = brightness, U and V are the color difference signals red and blue) connection is either as shown in the picture as Cinch/RCA sockets or as high quality BNC sockets. BNC offers a higher quality connection because of the better closure (rotation with latching).

The brightness Y (Luminance) and the two difference signals U and V (also called U=Cr for red and V=Cb for blue) are transmitted separately. Possibly the Sync signals are also separately led, then additionally two sockets/plugs/cables for HSync and VSync are needed. Otherwise the sync signals are included in the Y signal.

The YUV – Component signal corresponds to the format in which the data is stored on the DVD itself. It is therefore the most optimal connection and signal form for the transmission of video data from the DVD player to the playback device. Unfortunately there are hardly any TVs with YUV inputs. Only projectors are often designed for this kind of connection.

Some projectors also have a VGA socket which, depending on the model, can also accept YUV component signals. Unfortunately it is very difficult to find suitable adapters from Cinch/RCA or BNC to VGA. Additionally, separate sync pulses for HSync and VSync can be expected on two additional inputs, which requires a sync stripper to extract the two sync pulses from the Y signal. Which cables and adapters are needed depends strongly on the used devices. For a YUV connection at least 3 (maximum 5) high quality 75 Ohm video cables to the projector are needed, as well as possibly a YUV cable. Cinch/RCA or BNC to VGA adapter and a sync stripper if separate sync pulses are expected. If the DVD player has no YUV component outputs, but the projector accepts only YUV signals, but no RGB signals, there are also external converters from RGB to YUV.

In addition there is still for progressive Scan pictures as well as a Wide YUV connection possibility. From the specification this is a normal YUV connector, but can additionally transmit 32kHz video signals, as they are needed for full frames. For progressive scan playback, however, the corresponding playback devices are required. Normal televisions or projectors cannot process such signals.

Special features for NTSC playback

There is a problem with the use of NTSC DVDs and FBAS or FBAS DVDs. S-Video signals, which, depending on the DVD player and TV set, only produce a black/white picture. RGB and YUV signals are not affected by this, because they do not use a color carrier. The reason is the used NTSC color carrier which is not recognized by the TV set. Which solution possibilities there are and further points to this subject can be read up.