Abstract: The described video communication system incorporates multiple window display. One or more video transmission nodes provide macroblocks of video data available in a plurality of resolution levels. The transmission node encodes the macroblocks and assigns macroblock identifiers (IDs) to each macroblock. A receiving node receives a plurality of video sequences from a plurality of transmission nodes through a communication network. The receiving node thereafter eliminates macroblocks of video data that will not be displayed, such as in the case of portions of video that are hidden or overlapped. A macroblock translator also transforms the macroblock ID to a new macroblock ID which reflects the macroblock's position on the display screen as dictated by the user's window configuration. A decoder thereafter decompresses the video data one macroblock at a time, and provides the decompressed macroblock to a frame buffer. The frame buffer provides the window configured video data to a display.

Abstract: An overhead optical scanner is disclosed which uses commerical 60 Hz AC powered fluorescent lighting apparatus to illuminate the scanned objects. The image sensor of the scanner operates at a line scan rate which is in sync with the 60 Hz rate. The image sensor integrates the variations in illumination intensity received from the object over one complete 60 Hz cycle, thereby producing an electrical signal which is characteristic of a uniformly illuminated object.

Abstract: A flickerless video display for a gray scale image is obtained using binary picture elements in an interlaced field format. The flicker is eliminated by causing each display point on a line of the interlaced field to be vertically paired with and have an intensity equal to a display point which is located on an adjacent line. Incorporating this arrangement into a display system involves a modification only to the transmitter.