Specifications

C2-6104A OPERATION MANUAL

Normally, your foreground is the input (window) source and your background is the

lock source. This then allows you to superimpose any graphics or video input on

top of the lock source by keying out a certain color or range of colors in the input

source. Swapping them means that the input source moves to the background and

the lock source is now in front of it. Thus you are now keying out the lock source

colors to reveal the input source behind it.

Note that this is different to simply swapping over the input and lock sources as that

would affect the final output resolution – see examples below:

Input

source

Lock

source

Swap Foreground

(keyed)

Background

(non-keyed)

Output

resolution

XGA NTSC Off XGA NTSC NTSC

XGA NTSC On NTSC XGA NTSC

NTSC XGA Off NTSC XGA XGA

NTSC XGA On XGA NTSC XGA

(XGA is 1024x768)

You will see that the Swap between foreground and background has no effect on

the output resolution as this is always set by the Lock source.

The Min/Max parameters are used to select what range of Y (luminance/grey-scale)

values are made transparent within the selected window/lock source. In order to

key out part of an image, start with the max value and increase it until the required

lighter parts within the window/lock source disappear. Then adjust the min level to

bring back any darker parts of the image.

The Y Key softness option removes noise from the keyed image, generally at the

edges. Adjust as required to make the edges of the key as sharp or as soft as

desired. The noise is where the analog to digital process (A/D conversion) may not

sample a 50% brightness as being exactly 50% i.e. sometimes 49% and sometimes

51%. Increasing the softness value will broaden the range of keyed colors so that

the keying of images varies depending on how close a color is to the keyed-out

range.

The Y Key invert changes the keying characteristics with respect to what colors of

the foreground image you wish to ‘key out’.

Adjust keyers

Y Key min/max [ 0] [ 32]

Adjust keyers

Y Key softness [ 0]

Adjust keyers

Y Key invert [Off]