Patent attributes
The method and apparatus for processing pixel output signals from column lines in an imager having an array of pixels in rows and columns uses a sigma-delta type analog-to-digital converter to convert the output signals on each column line to digital signals and feeding them to a digital signal processor. The converter is monitored to stop sampling of a pixel with the detection of pixel saturation, which is carried out by counting a predetermined number of consecutive zeros in the converted signal. In addition, the next pixel in a column may be controlled to be read with the saturation of the previous pixel, and the next row of pixels may be controlled to be read with the saturation of the pixels in the previous row. Further, sets of a predetermined number of converter output samples are condensed by a decimator into binary numbers of predetermined bit length. The outputs of the decimators may be fed directly to the digital signal processor or they may be multiplexed to provide one or more inputs to the digital signal processor.
