Re: Reduce color saturation

Don Lancaster wrote:
Luhan wrote:

TSM wrote:

Hello, I want to build a circuit with trimmers to reduce the color
saturation of a signal going to a monitor. The signal is made up of
these wires: R, G, B, Sync, GND.

Do I need some IC? Are there any schematics to look at?

Thank you

--
TSM



Hmmm, since there is no luminance signal, just 3 color signals, it
would appear to be nary impossible to do what you want. These are not
3 voltages, but time varying signals. So no matter how you set the
individual levels, you cant reduce the color without reducing the
overall signal.

Nicht var?

Luhan


Nicht.

But you do have to similtaneously operate on all three signals.

Creating a HSB color space for manipulation.

Reconstruct the B/W luminance from 0.60 green + 0.29 red + 0.11 blue
Then adjust the differential deviation.

Alternately, use the darkest of the three signals to establish the gray level and differentially subtract out this level from the other two.

Free tools and utilities on my website.


This, of course, is easiest done in PostScript.


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: don@xxxxxxxxxx

Please visit my GURU's LAIR web site at http://www.tinaja.com
.

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