Re: 32 bitmap buffer Question

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// Find the byte on which this scanline begins
DWORD ByteIndex = (bmHeight - y - 1) *bmWidthBytes;
// Find the byte containing this pixel
ByteIndex += x*4;
// get the pixel's colors
BYTE B = buffer[ByteIndex]; // blue
BYTE G = buffer[ByteIndex+1];// green
BYTE R = buffer[ByteIndex+2];// red
BYTE A = buffer[ByteIndex+3];// alpha

// the color itself
COLORREF color = RGB(R,G,B);

where x ranges from 0..bmWidth
where y ranges from 0..bmHeight

The above will guide you through a 32bpp bitmap.


"BartMan" <MaskProg@xxxxxxxxxxxxxxxx> wrote in message
news:54ADBA52-6CB5-429F-9E8E-28BE7D1D4166@xxxxxxxxxxxxxxxx
Greetings,

I am currently working with a 32 bit bitmap buffer with a size of 640x480.
My question is how can I get information from within the buffer according
to
the pixel positions.
I have the raw buffer, and I want to move within the buffer by using some
sort of offsets to get specific data.

For Example:
BYTE* myBuffer contains the information for a 640x480 32 bitmap.
The actual size of the bitmap buffer is: 640*480*4 = 1228800.

Now I want information from a specific section.
(ie:) pixel (10,10) to (15,10).

Or how would I get a full line of information?
(ie:) (0,1) to (0,679)

I would like to come up with some sort of offset system to move around in
the buffer, but I can't seem to get it to work correctly.

Thanks in advance for any suggestions!



.

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