A system and process for broadcast and communication with bi-level or sketch
video
at extremely low bandwidths is described. Essentially, bi-level and sketch video
presents the outlines of the objects in a scene being depicted. Bi-level and sketch
video provides a clearer shape, smoother motion, shorter initial latency and cheaper
computational cost than do conventional DCT-based video compression methods. This
is accomplished by converting each color or gray-scale image frame to bi-level
or sketch image frame using adaptive thresholding method, compressing bi-level
or sketch image frames into bi-level or sketch video using adaptive context-based
arithmetic coding method. Bi-level or sketch video is particularly suitable to
such small devices as Pocket PCs and mobile phones that possess small display screen,
low bandwidth connection, and light computational power.
