CHAPTER 2 THEORETICAL FOUNDATION 2.1 Theoretical Foundation This Chapter Provides Detailed Explanations of Concepts and Jargons
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8 CHAPTER 2 THEORETICAL FOUNDATION 2.1 Theoretical Foundation This chapter provides detailed explanations of concepts and jargons used in the later chapter of this thesis. All the concepts and jargons are clarified in order to support the development of the mobile application. 2.2 History of Barcode In 1948 Bernard Silver (1924–63), a graduate student at Drexel Institute of Technology in Philadelphia, USA overheard the president of a local food chain asking one of the deans to research a system to automatically read product information during checkout[4]. Silver then told his friend Norman Joseph Woodland about the request and they started creating various systems. Their first system that fulfills the required task used ultraviolet ink. Unfortunately this method is proved to fade and was fairly expensive. Convinced that his system is workable, Woodland continued working on the system. He formed his first barcode from sand on the beach when "I just extended the dots and dashes downwards and made narrow lines and wide lines out of them."[5] To read them, he adapted technology from optical soundtracks in movies, using a 500-watt light bulb shining through the paper onto an RCA935 photomultiplier tube (from a movie projector) on the far side. He later decided that the system would work better if it were printed as a circle instead of a line, allowing it to be scanned in any direction. On 20 October 1949 Woodland and Silver filed a patent application for "Classifying Apparatus and Method", in which they described 9 both the linear and bullseye printing patterns, as well as the mechanical and electronic systems needed to read the code [6]. In 1959, after receiving his master degree at MIT, David Collins developed a system using blue and yellow reflective stripes. The reflected light from the stripes was captured using a photomultipliers, filtered blue or yellow. Collins’ system was implemented for automatically indentifying rail cars. The system was first tested by Boston and Maine Railroad in 1961 and in 1967 the Associations of American Railroads (AAR) accepted it as a standard for the entire North American railroad cars. Unfortunately, the system was abandoned in the late 1970s due to two main reasons, the economic downturn and the system was found to be easily fooled by dirt reducing the accuracy greatly. Although the railroad project proves to be unsuccessful, the need of quick item identification does not ended here. Later on, a toll bridge in New Jersey requested that a similar system be developed so that it could quickly scan for cars that had paid for a monthly pass. Then the U.S. Post Office requested the development of a system to keep track of the trucks entering and leaving their facilities. These applications required special retroreflective labels. Finally, Kal Kan asked the Sylvania team to develop a simpler (and cheaper) version which they could put on cases of pet food for inventory control. This, in turn, led to the grocery industry's interest [7]. 2.3 1D Barcode A barcode is a representation of data that stored certain data of certain products. Barcode is recognized by an optical reading machine. The first generation of 10 barcode originally uses variation in widths and spacings of parallel lines to represent data(s), which is commonly known as 1D (1 dimensional/linear) barcodes or symbologies. This system of representing data into a form of symbology is mainly used for Auto ID Data Capture (AIDC) tasks. The 1D barcodes has prevailed for a long period of time in satisfying the need of representing data for different applications. There are many different standards available for 1D barcodes. Out of the available standards in the world, one common type of standards used to label retail products worldwide is UPC barcode. Other common standards are EAN, Code 25, Code 128, etc. Each different barcode standards is used for different kind of application. Some of these barcode standards are also proprietary to only use in certain nation. See the table 2.4.1 for more references. Figure 2 – Linear Barcodes Continuous Bar Symbology or Uses widths discrete Worldwide retail, GS1 U.P.C. Continuous Many approved 11 Old format used in libraries, Codabar Discrete Two blood banks, airbills Code 25 – Non- interleaved 2 of Continuous Two Industrial (NO) 5 Code 25 – Interleaved 2 of Continuous Two Wholesale, Libraries (NO) 5 Code 39 Discrete Two Various Code 93 Continuous Many Various Code 128 Continuous Many Various Code 128A Continuous Many Various Code 128B Continuous Many Various Code 128C Continuous Many Various Code 11 Discrete Two Telephones CPC Binary Discrete Two Post office DUN 14 Continuous Many Various Addon code (Magazines), GS1 EAN 2 Continuous Many approved Addon code (Books), GS1 EAN 5 Continuous Many approved EAN 8, EAN Worldwide retail, GS1 Continuous Many 13 approved 12 Facing Identification Continuous One USPS business reply mail Mark GS1-128 (formerly known as UCC/EAN- 128), Continuous Many Various, GS1 approved incorrectly referenced as EAN 128 and UCC 128 GS1 DataBar formerly Reduced Space Continuous Many Various, GS1 approved Symbology (RSS) HIBC (HIBCC Bar Code Standard) Non-retail packaging levels, ITF-14 Continuous Many GS1 approved Latent image Neither Tall/short Color print film 13 barcode Pharmacode Neither Two Pharmaceutical Packaging Catalogs, store shelves, Plessey Continuous Two inventory PLANET Continuous Tall/short United States Postal Service POSTNET Continuous Tall/short United States Postal Service United States Postal Service, Intelligent Mail replaces both POSTNET and Continuous Tall/short Barcode PLANET symbols (Previously known as OneCode) Used for warehouse shelves and MSI Continuous Two inventory PostBar Discrete Many Canadian Post office RM4SCC / KIX Continuous Tall/short Royal Mail / Royal TPG Post Used in Japan, similar and JAN Continuous Many compatible with EAN-13 Telepen Continuous Two Libraries, etc (UK) Table 2.3.1 – List of 1D or Linear Barcodes Barcodes have many applications up until today. Some common uses of 1D barcodes up until today are as follows: • Almost every item purchased from a grocery store, department store, and mass merchandiser has a UPC barcode on it. 14 • Used on patient identification, enabling clinical staff to instantly access patient’s data, including medical history, allergy warnings and other potentially life-saving medical information. • Since 2005, airlines use an IATA-standard 2D barcode on boarding passes (BCBP), and since 2008 2D barcodes sent to mobile phones enable electronic boarding passes [8]. Problem with 1D barcode is it can only represent limited amount of data in a given printing area. For example, UPC code can only store 12 digits and not alphanumeric characters. Along with the growth of technology, the need of representing more data into barcode raise. There is a need for storing richer data representation, but without consuming too big of a printing space. 2.4 2D Barcode 1D barcode has been commonly used for representing data. The data embedded within the black and white vertical bars usually contain a key into a database that contains more detailed information. Yet many end users wanted to code more information. They wanted the bar code to be a portable database rather than just a database key [9]. In 1984 the trend to portable databases began when the Automotive Industry Action Group (AIAG) published an application standard for shipping and parts identification labels which consisted of four “stacked” Code 39 bar codes. These stacked bar codes contained part number, quantity, supplier, and serial number [10]. 15 The very first real 2D barcode ever implemented is the Code 49 barcode. It was introduced by Intermec Corporation in 1988. Code 49 2D barcode is still adapting the idea of using “stacked” 1D barcode. The motivation behind creating 2D barcode standards is to create a portable database in a little space as possible. In understanding the term 2D barcodes, it is essential to understand the difference between stacked symbologies and matrix code. Stacked symbologies, or multi-row code is a code that made out of several linear barcode stacked together. Each linear code contains data representing for different field value and each linear barcode may vary in sizes. On the other hand, Matrix code applies to 2-D codes that code the data based on the position of black spots within a matrix. Each black element is the same dimension and it is the position of the element that codes the data [11]. 2D barcode is capable to more data compared to 1D barcode. Data is stored along both height and width of the 2D barcode. Specifically 2D barcodes can hold about 2,000 bytes of data, or enough to encode some text and a compressed image file [12]. 2D barcodes can contain as many as 4,000 alphanumeric characters depending on size and type [13]. As more data are embedded in 2D barcode, the size of the code will increases both horizontally and vertically, saving more spaces compared to 1D barcode. Similar to 1D barcodes, up to today there are many 2D barcode standards that are available. Among the many standards available in the world, there are 2 standards that are widely used, Data Matrix code and QR code. Data Matrix codes are more popular and becoming a standard in the US and Europe, while 16 QR codes are more popular in Japan. A more complete reference of available 2D barcodes can be seen from table 2.5.1. Figure 3 – 2D Barcodes Symbology Notes 3-DI Developed by Lynn Ltd. ArrayTag From ArrayTech Systems. Designed by Andrew Longacre at Welch Allyn (now Aztec Code Hand Held Products). Public domain. Small Aztec Code Space-saving version of Aztec code. Chromatic an artistic proposal by C.