| 摘要 |
<p>PURPOSE:To precisely measure the propagation velocity of a radio wave by extracting a connection edge part which becomes an upward projection form on an edge picture image as an edge segment and outputting the position coordinate value of each part, a primary differentiated value and a secondary differentiated value. CONSTITUTION:In regard to an edge segment obtained by edge extraction processing, a detection part 1 examines whether the size of the circumscribed rectangle is larger than a certain reference value and only the write of a processed flag is executed. In regard to a large segment satisfying the reference value, a primary differential output part 13 calculates a two-dimensional inclination on an edge image at its image position to output. Further, a secondary differential output part 14 outputs a secondary differentiated value by taking the difference a primary differentiated value and another primary differentiated value of a neighboring edge picture element. The extraction of an edge segment is completed by the above operation.</p> |
