A SMART CCD IMAGE SENSOR WITH REAL-TIME PROGRAMMABLE PARALLEL CONVOLUTION CAPABILITIES

A fully parallel focal plane charge-coupled device (CCD) array which p erforms image acquisition and convolution with arbitrary kernels is pr esented, The real-time programmable spatial convolution is generated f or all pixels in parallel during the exposure. The 2-D convolution is performed by shifting a charge pattern in two dimensions and the expos ure time is varied in proportion to the weight of each kernel coeffici ent. The problem of negative weights can be solved by taking the diffe rence of two convolutions each with only positive weights. The CCD was fabricated using a standard CMOS/CCD process. Convolutions have been performed with a variety of linear filters that are commonly used in m achine vision. Typical rms deviations from the ideal filter characteri stics are between 1-2% of the largest kernel tap value. Results and pr actical applications of this work are discussed.