Crease detecting method and crease detecting device for scanned image

The invention provides a crease detecting method and a crease detecting device for a scanned image. The crease detecting method and the crease detecting device aim at a technical problem of incapability of normally performing subsequent processes such as optical character identification caused by high difficulty in effectively detecting the crease in the scanned image in prior art. According to the crease detecting method and the crease detecting device, through performing shallow image extraction on the scanned image, after an binary image of the shallow image is acquired, grid construction is performed on the binary image. A least path is searched through grid searching. Then the least path is restored to the original scanned image correspondingly, thereby obtaining the crease of the scanned image. The crease detecting method and the crease detecting device realize a technical effect of effectively acquiring the crease of the scanned image through searching the least path.