Image Sharpness Enhancement for Textile Testing

In an optical lens system, such as an optical microscope or a conventional camera, the depth of field is limited (i.e., only the objects within its depth range can be captured sharply). To capture focused images for objects out of the depth of field, focal positions must be adjusted. This is the so-called multifocal phenomenon of an optical imaging system. Obviously, the existence of the multifocal phenomenon has an adverse influence on image analysis. It is always desirable to have all objects across an image remain in focus. Image fusion is an effective way of solving the multifocal problem.1 Various fusion algorithms have been widely used in machine vision for medical, military, and other applications.