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wjlafrance/gist:2466303

Created April 22, 2012 19:25
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Processing pixels stored in 32-bit integers as AARRGGBB to create a negative image
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gistfile1.c
//Slow:
int r = (pixels[i] & 0x00FF0000 >> 16) * -1 + 255;
int b = (pixels[i] & 0x0000FF00 >> 8) * -1 + 255;
int g = (pixels[i] & 0x000000FF) * -1 + 255;
pixels[i] = r << 16 | b << 8 | g;
//Fast:
pixels[i] ^= 0x00FFFFFF;
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