Here is a small benchmark that try to compare several optimized Intel OpenCV library functions with their GPU analogs, written using OpenGL and GLSL shader language.
More information HERE.
Because I can’t resist, here is my score (Core 2 Duo 6600 default clocks, Radeon HD 3870 Catalyst8.5, WinXP 32-bit) with Resolution multiplier set to 4:
------------ CPU | GPU step1: 75.3 21.5 step2: 35.8 22.5 step3: 05.7 00.7 Total Time: 116.9 345.3
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