PURPOSE:To always exactly discriminate blip for each class by calculating the histogram of blip width, determining the allowable range of the blip width to be identified and discriminating the kind of the blip. CONSTITUTION:When a cartridge is loaded, a whole film is once taken up and blip 6a and 6b showing a block and page are read. Then, the blip 6a is integrated to a block count means 122 and the blip width of the blip 6b is detected by a blip width detecting means 124. Next, a CPU 102 calculates the histogram of the blip width by a histogram calculating means 128 and calculates allowable ranges alpha and beta by a blip width determining means 130. When retrieval is executed, the blip 6a and 6b are read while feeding the film and the kind of the blip is discriminated by a blip width discriminating means 132 based on the ranges alpha and beta. Thus, even when the kind or standard of the blip is changed, the blip can be always exactly discriminated.
展开▼
