Fixed pattern noise suppression in optical mouse by regulating estimator updates
AssigneePixart Imaging Inc.
InventorKevin Len-Li Lim
Life of this patent
Estimating the term…
Abstract
A method for performing fixed-pattern noise (FPN) estimation in an optical mouse includes: capturing a series of images to generate a plurality of frames; accumulating motion of the optical mouse to generate an accumulated distance; comparing the accumulated distance to a threshold; when the accumulated distance is greater than the threshold, enabling FPN estimation of the plurality of frames; and resetting the accumulated distance to zero.
Claims18
A method for performing fixed-pattern noise (FPN) estimation in an optical mouse, the method comprising:
- capturing a series of images to generate a plurality of frames;
- accumulating motion of the optical mouse according to correlation of two successive images of the plurality of frames to generate an accumulated distance;
- comparing the accumulated distance to a threshold;
- when the accumulated distance is greater than the threshold, enabling FPN estimation of the plurality of frames;
- and
- resetting the accumulated distance to zero after the FPN estimation is performed.
An optical mouse, configured to perform fixed-pattern noise (FPN) estimation, the optical mouse comprising:
- a pixel array circuit, configured to generate a plurality of frames corresponding to a series of images captured by the optical mouse;
- an image filter, configured to filter the plurality of frames to generate a series of filtered images;
- an FPN estimator, configured to generate an FPN estimated signal by averaging the series of filtered images in response to an update signal;
- a correlator, configured to determine correlation of two successive filtered images;
- a motion calculation circuit, configured to accumulate motion of the optical mouse according to the correlation;
- and
- an update regulator, configured to generate an accumulated distance according to the accumulated motion of the optical mouse, and configured to compare the accumulated distance with a threshold and generate the update signal to the FPN estimator when the accumulated motion is greater than the threshold;
- wherein the FPN estimator generates the FPN estimated signal when the update signal is received, and the FPN estimator sends a reset signal to the update regulator after the FPN estimation is performed, the reset signal for resetting the accumulated distance to zero.
Dependencies are inferred from the claim text.