Patent ID: 6119937
Filing Date: 2000-09-19
Classification: G06K

Abstract:
An information reproduction system comprising:reading means for reading a dot code from a recording medium on which multimedia information including at least one of audio information, image information and digital code data is recorded as an optically readable dot code;binarization means for binarizing an image signal corresponding to the dot code read by the reading means using a threshold so as to produce binary image data; andrestoring means for restoring data as original multimedia information by reading a dot code from the binary image data produced by the binarization means,said recording medium including a plurality of reference dots used by said binarization means for determining said threshold, andsaid binarization means including:means for detecting maximum and minimum values of an image signal level corresponding to the dot code;means for setting an internal ratio representing a ratio between the maximum and minimum values of the image signal level;means for calculating the threshold using the internal ratio and the maximum and minimum values of the image signal level;reference dot detection means for detecting the reference dots from the binary image data based on the calculated threshold; andthreshold setting means for determining an estimation value based on diameters of the reference dots detected by the reference dot detection means, for comparing the estimation value with a predetermined reference value and for re-setting the threshold by varying the internal ratio such that a difference between the estimation value and the predetermined reference value becomes equal to a predetermined target value.