GetPixelRGB from bitmap : how to ?

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From: Chris Lurner (c.lurner_at_lurner.it)
Date: 03/26/04 

Date: Fri, 26 Mar 2004 12:20:25 +0100

Hi all ,
I have created an application that capture the Screen with CreateDC().

Now I must get rgb (COLORREF) of all pixel .

With :
getRGB(hdc,xpos,ypos)

It's very very slow .
4sec for 640x480 image pixel :
I don't know the reason but it's too slow .

Any workaround for speed up this routine ?

I have think that if a create a Bitmap and using BitBlt
I can speed up the routine .

But the question is :
in wich way i can get the COLORREF of every pixel in BITMAP ?

tnx all !
c.l.

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