Accession Number : ADA097377


Title :   Automatic Methods in Image Processing and Their Relevance to Map-Making.


Descriptive Note : Final rept.,


Corporate Author : ARIZONA UNIV TUCSON DIGITAL IMAGE ANALYSIS LAB


Personal Author(s) : Hunt,B R


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a097377.pdf


Report Date : 11 Feb 1981


Pagination or Media Count : 226


Abstract : The behavior of digital cross-correlation algorithms as applied to image matching problems is examined in terms of the relationship between measurable image properties and algorithm characteristics. Statistical image quality measures are developed which could be employed in a preprocessor to predict the performance of automatic stereo-compilation equipment. The measures include quantity derived from the Cramer-Rao lower bound on the variance of any unbiased parameter estimator, various contrast measures such as variance, contrast modulation, and median absolute deviation, and a stationarity detector related to the variance gradient. These measures are based on image and correlator models which describe the behavior of correlation processors under conditions of low image contrast or signal-to-noise ratio, geometric distortion, and image non-stationarity. Computer simulations using synthetic imagery were performed to verify the various models, and indicate the potential for the use of image quality measures in the predicting of correlation behavior. Implications of the models in terms of correlation processor design and implementation are discussed. (Author)


Descriptors :   *DIGITAL MAPS , *STEREOMAPPING , SIGNAL PROCESSING , COMPUTERIZED SIMULATION , IMAGE PROCESSING , CONTRAST , SIGNAL TO NOISE RATIO , ANALYSIS OF VARIANCE , THESES , MONTE CARLO METHOD , LEAST SQUARES METHOD , COVARIANCE , MODULATION , CROSS CORRELATION , Q FACTOR


Subject Categories : Cartography and Aerial Photography


Distribution Statement : APPROVED FOR PUBLIC RELEASE