Abstract: Data compression of a sequence of digital frames is achieved by periodic sampling of the frames to form a sequence of "milestone frames". Each frame between the milestone frames is partitioned into a set of subarrays or fragments that cover the frame. Each fragment is projected one frame forward or backward, depending on the direction of tracking, and then displaced to a position yielding the closest match in the adjacent frame. The data available for transmission or storage is comprised of: a) compressed encoding of the milestone frames; and b) the displacements of the fragments from either adjacent frame. Unique to this invention is the construction of a motion trajectory at each pixel of each frame and the reconstruction of the intensity values of the pixels in those frames that are not milestone frames. The construction of motion trajectories is achieved by finding sequences of connected displacements of fragments.

Abstract: Pseudorandom values are produced using a memory and an arithmetic logic unit. The previous value is shifted four places to the left to form a shifted value. Next, the previous value is subtracted from this shifted value to form a subtracted value. The least significant bit of this subtracted value is complemented to form the new value.