Abstract: An MRI or other scanner (A) generates medical diagnostic data d(x,y) which has a Gaussian noise distribution for reconstruction by an imager (B) into an electronic image representation P(i,j) which may have a Gaussian or Rayleigh noise distribution. An image improving circuit (C) replaces each image pixel value P(i,j) from an image reconstruction means (32) with an improved pixel value P*(i,j) defined as follows:P*(i,j)=G(i,j)[P(i,j)-P(i,j)]+P(i,j)-n,where G(i,j) is a weighting function uniquely defined for each pixel (i,j), P is the mean of pixel values of neighboring pixels and n is the mean image noise. The weighting function is based on a diagnostic data noise variance and a pixel value variance V(i,j) corresponding to the same pixel. The data noise variance is derived by comparing a data value difference between each data value d(x,y) and its neighboring data values in a data memory (30). The smallest data value difference is indicative of the image noise variance.

Abstract: A signal processing circuit for enabling a computer to quickly scan a memory having stored signals which represent a video image includes a flag generator responsive to a lit pixel detector for providing a flag signal to the memory to be stored in an address location indicating the presence of at least one lit pixel in that row. Incoming video, which includes data and sync signals, is digitized and examined by the lit pixel detector and a flag signal is clocked into memory at a predetermined address. The computer scans these address locations, which lie in a single column, to determine the identity of rows having a flag signal. This eliminates the need for the computer to scan the entire address space to locate an object of interest.

Abstract: A system for converting an input bitmap image of one resolution to an output bitmap image of a different resolution. A mapping is defined between pixels in the input bitmap and pixels in the output bitmap. An error term is used to link successive output pixel determinations. For each output value determination, the values of the mapped input pixels are added to the error term to create a test value that determines what output is generated; the output value generated therefrom is then subtracted from the test value to create the next value of the error term. The conversion system is of particular advantage in converting an image having gray scale that is represented in a binary bitmap where gray scale is represented by the ratio of the number of "on" pixels to the number of "off" pixels. The present image conversion system performs a conversion such that the output bitmap represents such gray scale particularly well.

Abstract: In automatic assembly apparatus operating under electronic vision control, features on components to be assembled must be recognized and located in position and orientation so that a gripper mechanism may be directed to one component to pick it up and move it into correct position and orientation relative to the other component for assembly. The invention provides a known parallel projection optical system 8, 9, at the location of each component which provides a plan view for an electronic camera 11 of the components 20, 22 at constant scale regardless of lateral or axial component movements. The grey-level picture of each component provided by the camera is thresholded into a binarized picture at a threshold level which selects a primary component feature 27 within a part of the camera field of view which is certain to contain this feature.