A peripheral includes a scanning module and a control processing module. In a restoration mode, the scanning module performs a one-time scan operation on a punched document to obtain a visible light image and an infrared image. The infrared image includes an infrared hole image corresponding to one hole or multiple holes of the punched document. The visible light image includes a visible light hole image corresponding to one hole or multiple holes of the punched document. In the restoration mode, the control processing module, electrically connected to the scanning module, determines the infrared hole image according to the infrared image, determines the visible light hole image according to the infrared hole image and processes the visible light image into a final image according to the visible light hole image, wherein the final image does not contain the visible light hole image.