| 摘要 |
PROBLEM TO BE SOLVED: To extract the image of a target object existing in background noise or an echo without any threshold value adjustment by an operator by providing horizontal and vertical size filtering means and an image superimposing process. SOLUTION: Extraction of a target object from a two-dimensional image data obtained by a sonar device or the like is carried out on an image with a desired number of horizontal pigments and a desired number of vertical pigments or less by horizontal and vertical size filtering means 100, 200 with its pigment value level lowered. Horizontal and vertical filtering results 70, 71 are superimposed together by an image superimposing process 300, and a final filtering output 80 is obtained. The filtering means 100, 200 are provided with vertical and horizontal binding time harmonic bin extracting processes 113, 213 extracting a harmonic constituent in a space frequency axis outputted in response to horizontal and vertical sizes of a desired object, and also provided with target level compensating processes 500, 501 lowering a background level and compensating an image of a desired size alone. |
