| 摘要 |
<p>The digital signal values of adjacent picture points of pairs of points straddling the picture point currently being processed in every direction are compared in terms of only their more significant bits to determine which, if any, of the pairs involve a difference of value greater than a predetermined threshold. The determination that such a value difference is present is treated as the recognition of a picture contrast feature and causes, through operation of a read-only memory, the exclusion of such a picture point pair from the averaging process for producing a substitute value for the picture point currently under processing when the latter is found unusable by means of an error-detector. The resulting system for concealing errors detected in television picture avoids disturbing the outlines of picture features as other systems do which substitute averages of neighboring picture points for picture points found to be erroneous.</p> |
