Fundamentals of bar code information theory

T. Pavlidis, J. Swartz, Y.P. Wang
1990 Computer  
Symbol Technologies ntroduced about 20 years ago, bar codes have spread from supermarkets to department stores, the factory floor, the military, the health industry, the insurance industry, and more. The barcode industry uses the term symbology to denote be retrieved without access to a database. While a price look-up file (PLU) is necessary and convenient in a retail environment, this may not be the case at a distribu-To compare encoding and decoding schemes I each particular bar code scheme,
more » ... hile the term symbol refers to the bar code label requires us to first look tion center receiving from and shipping to remote warehouses or overseas depots. itself. The last few years have seen the introduction of many new symbologies, and an ongoing debate compares them with into information and coding theory-This The basic problem we face is that of encoding information on some medium using printing technology. Any such encoding has the following conflicting reauirements: article discusses each other and with schemes for encoding printed information on a substrate. Therefore, we need to look into information and problems and possible coding theory to make meaningful com-We want the code to have a high denparisons. solutions in encoding sity of information. We want to be able to read the code We want to minimize the cost of the We want to minimize the cost of the information. Early codes, in particular UPC (Universal Product Code), resulted from careful studies,' but such studies faced the technological constraints of 20 years ago and responded to the expected applications of distinction between the two forms in the that time. A more recent study' focused following example: The bar code of a only on some aspects of the encoding. The supermarket item consists of 11 digits, continuing drop in the price of computing which represent an identifying number but It is essential to look at all the factors to hardware makes feasible in the near future not a description of the product. For exreach practical and meaningful conclu-
doi:10.1109/2.55471 fatcat:aavskvgolzcchaq672ih7ayrjm