| 摘要 |
PURPOSE:To highly accurately detect a linear pattern such as a crack by dividing the memory area of an image memory and finding out and analyzing a projected waveform based upon a different projection angle at every area. CONSTITUTION:The memory area including a linear pattern LP is divided into plural square areas and a projection waveform is found out at every divided area. Then, the divided area is rotated by every prescribed angle to obtain projection waveforms based upon plural projecting directions. These projection waveforms are analyzed to determine the line direction theta, the line width W and line length L of a linear pattern specifying the shape and direction of a square-like linear segment. Consequently, a linear pattern such as a crack can be highly accurately detected. |
