Patent ID: 6922210
Filing Date: 2005-07-26
Classification: H04N

Abstract:
1. An image sensor comprising: a sensor array that outputs data signals representing one or more images of a scene, wherein the sensor array is fabricated in an integrated circuit; a memory space in communication with the sensor array and fabricated in the integrated circuit, the memory space being partitioned into a data memory and a threshold memory, the data memory comprising memory cells for storing values representing the data signals; the threshold memory, in communication with the sensor array, for storing threshold values corresponding to each of the memory cells; and an updating mechanism for updating the data memory for each of the one or more images; the update mechanism causing a group of the memory cells to be updated even though only a fractional number of the memory cells in the group need to be updated with new data signals, wherein the updating mechanism comprises an identifying mechanism for identifying locations of the fractional number of the memory cells to be updated and a read out mechanism for reading data out of the group of memory cells to a first buffer, wherein the first buffer is part of the memory space; and wherein the read out mechanism comprises, a multiplexer having a select input, first and second data inputs, and a data output; the first data input coupled to the first buffer and the second date input coupled to a second buffer receiving the new data signals, contents of the threshold memory applied to the select input; wherein the threshold memory controls the multiplexer to select which one of the first and second data inputs to pass to the data output; and wherein the data output is coupled to the data memory and to update the group of memory cells therein.