DARK CURRENT GRADIENT ESTIMATION USING OPTICALLY BLACK PIXELS

摘要

A method for removing background signal values from readout signal values generated by image pixels in a pixel array may include generating background signal values using optically black pixels formed around a border of the pixel array. The background signal values may be separated into blocks. Block average values may be calculated based on the background signal values included in each of the blocks. Corner regions of the pixel array may be free of image pixels and optically black pixels. Corner background signal values may be extrapolated based on the block average values. Image pixel background signal values may be interpolated based on the block average values and the corner background signal values. The image pixel background signal values may be subtracted from the readout values.

主权项

1. A method for determining background noise in a frame of image data, the method comprising:
receiving the frame of image data from an image sensor having an array of image pixels and a plurality of optically black pixels, wherein the frame of image data includes first background signal values from the optically black pixels; grouping the first background signal values into blocks; calculating block average values based on the first background signal values included in each respective block; and determining second background signal values for the image pixels in the array based on the block averages, wherein the second background signal values indicate an amount of background noise associated with the image pixels.