US Patent 7382935 Homogeneous and plain surface detection in optical navigation systems

One embodiment in accordance with the invention relates to detecting a homogeneous surface. A first surface image is received. A plurality of values are generated by performing a plurality of auto correlations with the first surface image and a copy of the first surface image. The plurality of values includes a first peak value. A determination is made as to whether a normalized second peak value of the plurality of values satisfies a defined condition associated with a value. If so, a homogeneous surface image filter is utilized with a second surface image.