Update on focal-plane image processing research

An update on research activities at Columbia University in the area of focal-plane image processing is presented. Two thrust areas have been pursued: image reorganization for image compression and image half-toning. The image reorganization processor is an integration of a 256 x 256 frame-transfer CCD imager with CCD-based circuitry for pixel data reorganization to enable difference encoding for hierarchical image compression. The reorganization circuitry occupies 2 % of the total chip area and is performed using three parallel-serial-parallel (SP') registers, a pixel resequencing block, nd a sampling block for differential output. The chip has achieved a CTE of 0.99994 in this new SP architecture, at an output rate of 83x103 pixels/sec (0.9996 at 2x106 pixels/sec) and an overall output amplifier sensitivity of 34EV/electron. The half-toning chip design has been described previously, and consists of a 256 x 256 frame transfer imager, a pipeline register, and comparator circuit. Functional testing of these elements is reported at this time.