Abstract: Apparatus that provides working storage for large image and data processing systems. The apparatus comprises a computer bus, a high speed backplane bus, a local area network, a central processing unit coupled to the computer bus, an Ethernet local area network interface coupled between the computer bus and the local area network, a plurality of bidirectional input/output interface cards coupled to the computer bus and the backplane bus, and a plurality of disk modules coupled to the computer bus and the high speed backplane bus. Each interface card comprises a plurality of bidirectional input/output ports coupled to a plurality of user workstations, a fiber optic interface, and a FIFO buffer. Each disk module comprises a plurality of storage units, one of which provides for storage of parity bits and the remainder of which provides for storage of data, and a distribution card coupled to the plurality of storage units.

Abstract: A filter which uses both an analog portion and a digital portion to optimize the filter performance. A simple analog filter provides a rough filtering of the input signal. The output of the analog filter is converted into digital form and supplied to a digital filter. The coefficients of the digital filter are changed by a digital computer in order to correct for the errors in the filtered signal produced by the analog filter. The coefficients necessary for the digital filter to provide an error offset are determined by comparing the filtered value of a test signal through the analog filter to an ideal filtered value of such test signal.