A short example for the BGRA to Grayscale Image conversion on an ARM (iPhone / ipad / iPod Touch ) Source for the neon_convert and neon_asm_convert functions from Khvedchenya Eugene @ http://computer-vision-talks.com: http://computer-vision-talks.com/2011-02-08-a-very-fast-bgra-to-grayscale-conversion-on-iphone/ Source for the FPS calculation: http://www.hatzlaha.co.il/150842/FAST%2DCorner%2DV2 (link isn't workign any more, kept to credit author).