Re: Color Channel Splitting

Subject: Re: Color Channel Splitting

From: Alex Drinkwater <email@hidden>

Date: Thu, 8 May 2008 20:03:31 +0000 (GMT)

Delivered-to: email@hidden

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This code in a CIFilter will let you selectively enable/disable Red, Green and Blue channels.

Use Boolean splitters attached to the Red Green and Blue inputs. The cables will be orange, but it will still work fine.

Enables/disables RGB channels

kernel vec4 selectChannels(sampler Image, float Red, float Green, float Blue)

{

// Sample input pixels

vec4 pix = sample(Image, samplerCoord(Image));

// Enable or enable channels

pix.r = (Red == 1.0) ? pix.r : 0.0;

pix.g = (Green == 1.0) ? pix.g : 0.0;

pix.b = (Blue == 1.0) ? pix.b : 0.0;

// Output

return pix;

}

Hope this helps,

a|x

http://machinesdontcare.wordpress.com

----- Original Message ----
From: neb <email@hidden>
To: email@hidden
Sent: Thursday, 8 May, 2008 7:38:39 PM
Subject: Color Channel Splitting

A simple problem, I know the answer is right in front of me but can't
seem to find it...

How would I go about splitting a single image feed into RGBA or HSBA
component channels, so that I can process each channel individually as
images, and then reassemble (or not) later on in the chain? I'm using
QC3 on leopard.

Thanks!

- Neb
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