Patent ID: 6918539
Filing Date: 2005-07-19
Classification: G06K

Abstract:
1. A method of reading out an optical data code, said method comprising the steps of: sequentially carrying out image-taking, code-extracting and decoding steps wherein said image-taking step comprises taking an image of an optical data code comprising visually identifiable symbols, said code-extracting step comprises extracting said optical data code in said image by carrying out a specified image processing on said image and said decoding step comprises carrying out a different image processing on said extracted optical data code and decoding optical data represented by said optical data code from results of said different image processing; obtaining a specified evaluation value for said optical data code in said image from results of processes carried out prior to said decoding step if said decoding step was successful in decoding said optical data; storing said evaluation value; and outputting change-showing data showing changes in said evaluation value with time by using said evaluation value and a plurality of earlier evaluation values that were stored previously.