TV One C2-5000 Series, Operation Manual

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C2-5000 Series Universal Scaler Operation Manual
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blue is the norm, it can be any color. Medium blue has become such a standard
that there is a paint color called Chroma Key Blue.
For a step-by-step tutorial on setting the values for a luminance key, refer back to
the quick start segment of this manual. In that documentation you were told to
adjust the min/max value of the Y channel until the key was clean and free of
objectionable image artifacts. The same basic procedure is used to set up a
Chroma key using the U and V channels but a more in depth discussion goes like
this:
Where the pixel color is within the luminance (Y) and chrominance (U & V)
minimum and maximum values, the pixel is 'keyed-out' and becomes
transparent. When not within the min/max limits, the pixel is displayed.
The key values are provided in YUV format in order to select luma (Y) and
chroma (U & V) keying. A simple method to set a key color to an on screen color
is to set all the YUV key min/max values to 0 and 255 - at which point all pixels
will become transparent.
Then increase the Y key min value until the required pixel color re-appears. Go
back a few steps until it disappears which gives you the Y key min value for that
pixel color. Do the same with the Y key max value, reducing it instead from 255
until the pixel appears and then retreating a few detents until it disappears again.
The methodology to accomplish this change is the same as for all other
adjustments: When you are parked on the LCD screen of interest, press the
Menu Select knob once and the brackets will begin to flash. Make your
adjustment and then press the knob. This stores your new value in temporary
memory. Rotate the Menu Select knob one detent to the right and press the knob
again, this will move the brackets to the right and cause them to start flashing in
their new position. Again make an adjustment and press the knob to store the
new value in temporary memory. Press and hold the knob down until you hear
the “Beep” in each case to make the change permanent.
Repeat the above for the U & V key min/max settings. You should then have the
YUV key min/max values for the required pixel color. Leaving the U & V Min/Max
values at 0 and 255 will create a Luminance key - where only the Y Key Min/Max
value has an effect.
Note: The C2-5200 also has adjustments for the SDI input, selectable between
NTSC and PAL. These adjustments set the conditions for the SDI lock input.