A disc cartridge for receiving a disc-like recording medium therewithin, including a disc insertion and removal port provided in the disc cartridge and being capable of inserting and removing the recording medium, the disc cartridge having an insertion and removal port opening and closing member. In the method, a contour containing a destination pixel and a plurality of contour pixels is produced and detected by using an edge detection method for a selected area in an original image. The underlay panel includes a slit extending along a vent axis, wherein the slit includes a selectively operable closure assembly extending therealong.