INTRODUCTION



INTRODUCTION

We live in an information age characterized by rapid change. Today's world moves faster than earlier eras, and the pace continues to speed up. Continuous developments with computer technology in manufacturing, distribution, communications, transportation, healthcare and other sectors have played, and continue to play, a large part in accelerating change.

For any business in this fast changing world, the importance of collecting and processing information on a timely basis is essential. Managers must act quickly to be effective to initiate changes in manufacturing or distribution, or to otherwise respond to new customer requirements. Doing so requires reliable information in real time or as close to it as possible.

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As computers have proliferated and data processing has become more powerful, the data collection function on which processing depends has not kept pace. Acquiring the fastest, most effective computer hardware and software available makes little sense if the system cannot acquire data accurately and expeditiously. A data collection gap, the difference between data processing and data collection, has been the result. Narrowing this data collection gap promises to improve the quality of information that serves as the basis for management decisions affecting production, productivity, and profitability.

Automation of the data collection function offers the only practical way to bring the pace of data collection more closely in line with data processing. Many manual methods, such as keyboard entry, are considered too slow, costly and error-prone to satisfy modern criteria. That is why automated data collection technology has expanded rapidly worldwide.

The automated data collection process has three phases:

Automatic identification is the essential first step, accomplished by attaching a bar code label to a part, document, package, personal identification badge or some other item to be tracked.

The data collection phase occurs when a part moves in or out of inventory, a work piece comes in or out of a given stage in the manufacturing process, and/or an employee checks in or out of work. These actions are instantly and accurately captured by scanning the bar code label. Scanners can read information far faster than humans can write or type, and they are far more accurate. Compared to the average human-transcription error rate of one per 300 characters, the automated error rate is in the range of one per 3 million.

Compiling and computer system input occurs when scanned data is compiled into a central point and manipulated into a form appropriate to the data stream of a host computer. The upshot is accurate data automatically captured as each event occurs, thus permitting management decisions based on solid, current information.

Automated data collection is seen as the key to improving control and providing management with more timely, more accurate, and therefore more valuable information. Increased productivity and reduced costs are the key benefits of automated data collection. The return on investment for automated data collection is typically one year, and often substantially less.

BARCODE

In a simplest form, barcode is a set of bars and spaces representing alphabet and numeric data for identification of a particular product, service or a process.

A barcode is an optical machine-readable representation of data, which shows data about the object to which it attaches. Originally, barcodes represented data by varying the widths and spacings of parallel lines, and may be referred to as linear or 1 dimensional (1D). Later they evolved into rectangles, dots, hexagons and other geometric patterns in 2 dimensions (2D). Although 2D systems use a variety of symbols, they are generally referred to as barcodes as well. Barcodes originally were scanned by special–optical scanners called barcode readers, scanners and interpretive software are available on devices including desktop printers and smartphones.

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A bar code is simply a series of stripes (usually black) on a light background (usually white) that can be scanned and read directly into a computer. They are interpreted virtually instantaneously and without errors by a bar code reading system. The elements (bars and spaces) in a bar code symbol must be of a consistent, proportional thickness and thinness. The widest element could be as thick as a pencil or as thin as a business card, as long as the corresponding thin bars and spaces in the bar code remain proportionally thin.

Bar codes are read the same way that people read text from a page; the reflectance and absorption of light. A light of a given wavelength is beamed and moved across a bar code at a consistent speed. The reflected light is measured with a photoreceptor, tuned to look for light of the given wavelength. The off- and- on (white and black) pattern of the bar code creates an electrical wave that is sent on to a computer chip called a “ decoder.” The decoder then deciphers the signal into something the waiting computer understands.

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The first use of barcodes was to label railroad cars, but they were not commercially successful until they were used to automate supermarket checkout systems, a task for which they have become almost universal. Their use has spread to many other tasks that are generically referred to as Auto ID Data Capture (AIDC). The very first scanning of the now ubiquitous Universal Product Code (UPC) barcode was on a pack of Wrigley Company chewing gum in June 1974.

Other systems have made inroads in the AIDC market, but the simplicity, universality and low cost of barcodes has limited the role of these other systems until the first decade of the 21st century over 40 years after the introduction of the commercial barcode. It costs under 0.5¢ (U.S.) to provide a barcode. It was not until late 2008 when the barcode began getting its first significant challenge in the retail industry from radio frequency identification or RFID specifically passive Radio Frequency Identification RFID in 2011 costs about 5¢ to 15¢ per tag. RFID is seen as the clear replacement to bar code since it is an order of magnitude more productive allowing scans of thousands at a time. In 2010 a Korean company successfully printed a chip and inlay onto paper substrate and predicted a 3 cent tag by 2012.

Barcode technology is the best-known and most widely used method of Automatic Identification. Automatic Identification or “Auto ID” encompasses the automatic recognition and recording of data, most commonly through the printing and reading of information encoded in barcodes thereby eliminating risk of human error.

Early applications of barcode scanning, which included retail point of sale, item tracking and inventory control, have been expanded to include more advanced applications such as time and attendance, work-in-process, quality control, sorting, order entry, document tracking, shipping and receiving, and controlling access to secure areas.

Barcodes have been instrumental in revolutionizing, and significantly increasing efficiency and productivity across the entire supply chain from manufacturers to distributors to retailers worldwide. The packet of Wrigley’s chewing gum was the firs-ever product to be barcoded and scanned at Marsh’s supermarket in Troy.

HISTROY OF BARCODE

The industrial use of barcodes can be traced back as far as the 1960s, in some cases as a means to identify railroad cars. Common linear barcodes started appearing on grocery shelves in the early 1970s as the UPC barcode to automate the process of identifying grocery items. Today, barcodes are just about everywhere and are used for identification in almost all fields of business. When barcode technology is utilized in business processes, procedures are automated to increase productivity and reduce human error. Barcoding should be used whenever there is a need to accurately identify or track something.

In 1948 Bernard Silver, a graduate student at Drexel Institute of Technology in Philadelphia, Pennsylvania, USA overheard the president of the local food chain, Food Fair, asking one of the deans to research a system to automatically read product information during checkout. Silver told his friend Norman Joseph Woodland about the request, and they started working on a variety of systems. Their first working system used ultraviolet ink, but this proved too subject to fading and was fairly expensive.

Convinced that the system was workable with further development, Woodland left Drexel, moved into his father's apartment in Florida, and continued working on the system. His next inspiration came from Morse code, and he formed his first barcode from sand on the beach. "I just extended the dots and dashes downwards and made narrow lines and wide lines out of them." 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 both the linear and bullseye printing patterns, as well as the mechanical and electronic systems needed to read the code. The patent was issued on 7 October 1952 as US Patent 2,612,994. In 1951, Woodland moved to IBM and continually tried to interest IBM in developing the system. The company eventually commissioned a report on the idea, which concluded that it was both feasible and interesting, but that processing the resulting information would require equipment that was some time off in the future.

Collins at Sylvania

During his time as an undergraduate, David Collins worked at the Pennsylvania Railroad and became aware of the need to automatically identify train cars. Immediately after receiving his master's degree from MIT in 1959, he started work at GTE Sylvania and began addressing the problem. He developed a system called KarTrak using blue and yellow reflective stripes attached to the side of the cars, encoding a six-digit company identifier and a four-digit car number. Light reflected off the stripes was fed into one of two photomultipliers, filtered for blue or yellow.

The Boston and Maine Railroad tested the KarTrak system on their gravel cars in 1961. The tests continued until 1967, when the Association of American Railroads (AAR) selected it as a standard, Automatic Car Identification, across the entire North American fleet. The installations began on October 10, 1967. However, the economic downturn and rash of bankruptcies in the industry in the early 1970s greatly slowed the rollout, and it was not until 1974 that 95% of the fleet was labeled. To add to its woes, the system was found to be easily fooled by dirt in certain applications, and greatly affected accuracy. The AAR abandoned the system in the late 1970s, and it was not until the mid-1980s that they introduced a similar system, this time based on radio tags.

The railway project had failed, but a toll bridge in New Jersey requested a similar system so that it could quickly scan for cars that had purchased a monthly pass. Then the U.S. Post Office requested a system to track trucks entering and leaving their facilities. These applications required special retroreflective labels. Finally, Kal Kan asked the Sylvania team for a simpler (and cheaper) version which they could put on cases of pet food for inventory control. This, in turn, interested the grocery industry.

Computer Identics Corporation

In 1967, with the railway system maturing, Collins went to management looking for funding for a project to develop a black and white version of the code for other industries. They declined, saying that the railway project was large enough and they saw no need to branch out so quickly.

Collins then quit Sylvania and formed Computer Identics Corporation. Computer Identics started working with helium-neon lasers in place of light bulbs, scanning with a mirror to locate the barcode anywhere up to several feet in front of the scanner. This made the entire process much simpler and more reliable, as well as allowing it to deal with damaged labels by reading the intact portions.

Computer Identics Corporation installed one of its first two scanning system in the spring of 1969 at a General Motors (Buick) factory in Flint, Michigan. The system was used to identify a dozen types of transmissions moving on an overhead conveyor from production to shipping. The other scanning system was installed at General Trading Company's distribution center in Carlsbad, New Jersey to direct shipments to the proper loading bay.

WHY USE BARCODES?

The use of barcode technology in an industrial setting can be traced back as far as the 1960s, with some early implementations to identify railroad cars. Common barcodes began appearing on grocery store shelves in the early 1970s as the UPC code to automate the process of identifying grocery items. Today, barcodes are just about everywhere and are used for identification in almost all areas of business. When barcodes are implemented in business processes, procedures can be automated to reduce human error and increase productivity. Barcoding should be considered whenever there is a need to accurately identify or track something.

BARCODE TECHNOLOGY

As changes in the world of commerce happen faster and faster, business owners have to scramble at an ever increasing pace just to keep up. Day to day office tasks such as stock control, asset management, and other chores can be performed much more productively because of the advances in computer technology.

These developments have given us the gift of barcode technology. However, it used to be that only big businesses could afford the large monetary outlay needed to purchase such a gift. However, this is no longer the case, as smaller companies can now purchase specially designed systems that will allow them to flourish in their areas of expertise with increased productivity and a better bottom line. While the systems have been modified, they still deliver the punch of those designed for much larger companies. If that weren't enough, they come ready to use, right out of the packaging.

You might think that only grocery stores make use of barcode technology, but look again. Everything from warehousing and distribution, manufacturing, government, retail stores, health care facilities and places of learning, use these products. A list of all the vast uses and advantages of barcodes and barcode scanners, would take up far too much space, so here are just some of the major points that might be of use to your company.

Barcode scanners can be put to use in all sorts of facilities, not just retail outlets. With Bluetooth and wireless capability these handheld scanners can give the user free access to all areas of a warehouse or office building or medical facility. This way inventories can be tracked from anywhere. Many hospitals use them to inventory their stocks of medicine, equipment, and to keep track of patients. In a manufacturing plant it is possible to follow raw material inventory, right to when it emerges as finished goods.

Keeping customers happy and getting them the items they have ordered on time is a very essential part of doing business. Old methods of obtaining jobs, creating invoices and work orders and sending them in the mail, or by courier, is old and out-dated. Barcode scanners and printers make it easy to take orders directly and fulfill them. From start to finish there is virtually no chance that a mistake will occur because everything is coded and can be tracked or traced all along the production line.

Barcode technology can help advertise and promote a business in amazing new ways. Try using a barcode on the products you produce instead of merely printing your website address on them. When this barcode is scanned by a camera phone, your customers will have instant access to the appropriate wireless-enabled website. This way you can promote special new products, upcoming sales, concerts, or open houses. Imagine the possibilities you can make happen with relatively simple, easily implemented barcode technology. This, in effect, turns what you produce into little ambassadors, or an unpaid sales force, working for you twenty four hours a day.

Law firms can really use barcode technology in this day and age as well. With a huge client database and an even bigger amount of transcripts and documents, something simple is required to keep track of all this data. A simple solution is to barcode each client file. It can even be time-coded so CCD scanners enable administrators to see how much time each lawyer spends interacting with each of their clients. It makes billing and all aspects of office administration much simpler.

The era of barcodes is here to stay, and the sooner a small to medium-sized business, or department of a large corporation embraces this technology, the more efficiently it will perform on a day to day basis. Then when year-end comes around, the bottom line will be better too.

Since their invention more than 50 years ago, bar codes have been enablers for accurate data capture, the rapid movement of goods, and all types of automation. Whether at the Point-of-Sale, in a hospital, or in a manufacturing environment these little black and white images deliver incredible value.

There are many different bar code symbologies, or languages. Each symbology has its own rules for encoding characters (e.g., letter, number, punctuation), printing, decoding requirements, and error checking.

Bar code symbologies differ both in the way they represent data and in the type of data they can encode: some encode numbers; others encode numbers, letters, and a few punctuation characters; still others offer encodation of the 128 or 256 ASCII character sets. Recently unveiled symbologies include options to encode characters in any language as well as specialized data types.

Bar codes in common use are covered by international standards. International standards also cover print quality measurements and equipment.

Bar code technology standards define:

• Rules for representing data in an optically readable format,

• Rules and techniques for printing or marking,

• Reading and decoding techniques, and

• Rules for measuring the quality of printed/marked symbols

RFID Technology

Radio Frequency Identification (RFID) is still in its infancy as a technology, and implementation is usually many times more expensive compared to that of barcoding. There are many additional issues to consider with RFID such as those listed in the Disadvantages of RFID section in IDAutomation's RFID FAQ. However, RFID also has many advantages over barcoding. In some cases, these advantages outweigh the disadvantages and high cost of implementing RFID technology. Decision makers must carefully consider whether RFID really provides an advantage the traditional use of barcodes in their business model.

Barcode Technology: How it works?

Barcodes are typically made up of a prefix that identifies the company (or manufacturer) and a suffix that identifies the product (or SKU).

GS1 (formerly, EAN) is the world’s most widely adopted supply chain standard for goods, services, assets and location identification since 1977. Over 1 million companies of all sizes use GS1 standards to execute more than 5 billion transactions a day.

A Barcode system consists of three components:

• Origin: You must have a source of barcodes. These can be printed on source or on-demand using thermal barcode printer and software.

• Reader: A reader is used to read and decode barcodes. A reader can be either hand held or portable or mounted as a fixed device.

• Computer System: A barcode system is usually a part of larger system or application software for collecting and managing information.

Thousand of retail stores around the world, and a rapidly increasing number in India use barcodes to collect information at the checkout.

On its packaging each product carries a barcode which uniquely identifies it and distinguishes it from all others in a shopping basket. At the checkout, an automatic scanner reads each barcode. The barcode is decoded to reveal the Article number it represents. This number is passed to computer, which matches it against a file and retrieves the price to be charged along with a description of the product. Both price and description are then printed on receipt.

Retailers for the first time can record the identity of every item sold. They can reorder more quickly, reduce their stocks and have financial and marketing information at their fingertips with unbelievable speed, accuracy and detail.

USE

Barcodes such as the UPC have become a ubiquitous element of modern civilization. Some modern applications of barcodes include:

• Almost every item other than fresh produce from a grocery store, department store, and mass merchandiser has a UPC barcode on it. This helps track items and also reduces instances of shoplifting involving price tag swapping, although shoplifters can now print their own barcodes.

• Barcodes are widely used in shop floor control applications software where employees can scan work orders and track the time spent on a job.

• Retail chain membership cards (issued mostly by grocery stores and specialty "big box" retail stores such as sporting equipment, office supply, or pet stores) use bar codes to uniquely identify a consumer. Retailers can offer customized marketing and greater understanding of individual consumer shopping patterns. At the point of sale, shoppers can get product discounts or special marketing offers through the address or e-mail address provided at registration.

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Example of barcode on a patient identification wristband

• When used on patient identification, barcodes permit clinical staff to instantly access patient data, including medical history, drug allergies, etc.

• Document Management tools often allow for barcoded sheets to facilitate the separation and indexing of documents that have been imaged in batch scanning applications.

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Barcoded parcel sent from Ukraine

• The tracking of item movement, including rental cars, airline luggage, nuclear waste, mail, express mail and parcels.

• Tracking the organization of species in biology. The barcode assigned is based on the CO1 gene.

• 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.

• Recently, researchers placed tiny barcodes on individual bees to track the insects' mating habits.

• Barcoded entertainment event tickets allow the holder to enter sports arenas, cinemas, theatres, fairgrounds, transportation, etc. This can allow the proprietor to identify duplicate or fraudulent tickets more easily.

• They can track the arrival and departure of vehicles from rental facilities.

• Barcodes can integrate with in-motion checkweighers to identify the item being weighed in a conveyor line for data collection

• Some 2D barcodes embed a hyperlink to a web page. A capable cellphone might be used to read the barcode and browse the linked website, which can help a shopper find the best price for an item in the vicinity.

• In the 1970s and 1980s, software source code was occasionally encoded in a barcode and printed on paper. Cauzin Softstrip and Paperbyte are barcode symbologies specifically designed for this application.

• The 1991 Barcode Battler computer game system, used any standard barcode to generate combat statistics.

• In 1992 the Veterans Health Administration developed Bar Code Medication Administration system (BCMA).

• In the 21st century many artists started using barcodes in art, such as Scott Blake's Barcode Jesus, as part of the post-modernism movement.

• Today, barcodes are issued by GS1, the most widely used supply chain standards system in the world.

SYMBOLOGIES

The mapping between messages and barcodes is called a symbology. The specification of a symbology includes the encoding of the single digits/characters of the message as well as the start and stop markers into bars and space, the size of the quiet zone required to be before and after the barcode as well as the computation of a checksum.

Linear symbologies can be classified mainly by two properties:

• Continuous vs. discrete: Characters in continuous symbologies usually abut, with one character ending with a space and the next beginning with a bar, or vice versa. Characters in discrete symbologies begin and end with bars; the intercharacter space is ignored, as long as it is not wide enough to look like the code ends.

• Two-width vs. many-width: Bars and spaces in two-width symbologies are wide or narrow; how wide a wide bar is exactly has no significance as long as the symbology requirements for wide bars are adhered to (usually two to three times wider than a narrow bar). Bars and spaces in many-width symbologies are all multiples of a basic width called the module; most such codes use four widths of 1, 2, 3 and 4 modules.

Some symbologies use interleaving. The first character is encoded using black bars of varying width. The second character is then encoded, by varying the width of the white spaces between these bars. Thus characters are encoded in pairs over the same section of the barcode. Interleaved 2 of 5 is an example of this.

Stacked symbologies repeat a given linear symbology vertically.

The most common among the many 2D symbologies are matrix codes, which feature square or dot-shaped modules arranged on a grid pattern. 2-D symbologies also come in circular and other patterns and may employ steganography, hiding modules within an image (for example, DataGlyphs).

Linear symbologies are optimized for laser scanners, which sweep a light beam across the barcode in a straight line, reading a slice of the barcode light-dark patterns. Stacked symbologies are also optimized for laser scanning, with the laser making multiple passes across the barcode.

In the 1990s development of charge coupled device (CCD) imagers to read barcodes was pioneered by Welch Allyn. Imaging does not require moving parts, like a laser scanner does. In 2007, linear imaging had begun to supplant laser scanning as the preferred scan engine for its performance and durability.

2-D symbologies cannot be read by a laser as there is typically no sweep pattern that can encompass the entire symbol. They must be scanned by an image-based scanner employing a CCD or other digital camera sensor technology.

The type of barcode that should be used may depend on several variables, including the following:

1. Standards and mandates

2. Purpose and use

3. Data encoded

4. Printing and/or decoding methods

There are several different types of barcode standards for different purposes - these are called symbologies. Each type of symbology (or barcode type) is a standard that defines the printed symbol and how a device, such as a barcode scanner, reads and decodes the printed symbol.

If an industry standard has already been established for the intended implementation, the standard should be implemented. If a standard does not exist for the chosen implementation, several symbologies are available to choose from.

Industry standards are usually established when multiple parties or companies are involved in the ID process. The standard is not necessarily the same as the barcode symbology. Barcode standards define how to use the barcode symbology in a particular situation. For example, the two standards to create ISBN barcodes for books and generate ISSN barcodes for periodicals both use EAN-13 to encode data into the barcode, but have different methods depending on the specific ISBN & ISSN standards.

In other point of view, a bar code “ symbology” is to bar codes in much what a particular alphabet is to language. Different symbologies of bar codes use different combinations of bars and spaces to represent different characters. Bar code symbologies, like languages, are given different names, like Code 39, UPC, PDF417, DataMatrix…

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Established Barcode Standards:

|Established Standard |Purpose |Barcode Symbology |

|ABC Codabar |blood bank tracking |Codabar |

|AIAG |automotive item identification |Data Matrix |

|DOD UID |unique identifier for US Department of Defense |Data Matrix |

|EAN-8 & EAN-13 |items for sale worldwide |UPC/EAN |

|EAN-14 |shipping cartons |Interleaved 2 of 5 or Code 128 |

|GTIN |global trade identification |Code 128 |

|GTIN-12 |global trade identification |UPC |

|GTIN-13 |global trade identification |EAN |

|GTIN-14 |global trade identification and POS |GS1-DataBar |

|ISBN, ISSN & Bookland |books and periodicals |EAN-13 with UPC/EAN |

|LOGMARS |US Department of Defense |Code 39 |

|MIL-STD-130 |US Department of Defense |Data Matrix |

|POSTNET |US mail |POSTNET |

|SCC-14 |shipping cartons |Interleaved 2 of 5 or Code 128 |

|SISAC |serial numbers for serial publications |Code 128 |

|SICI Code |serial numbers for serial publications |Code 128 |

|ISBT-128 |Blood, tissue and organ products |Code 128 |

|SSCC-18 |shipping cartons |Code 128 |

|USPS Special Services |US mail special services |Code 128 |

|UCC12, UPC-A & UPC-E |items for sale in the USA and Canada |UPC |

|USPS Intelligent Mail |USPS mail routing and tracking |4 State |

One dimensional vs two Dimensional barcodes

Before beginning a discussion on two- dimensional bar code symbols, some clarifications must be made regarding one- dimensional symbols...

Typical bar code symbols obviously have both height and breadth. To most people, they’d be considered a two- dimensional object. So, why do we refer to them as one- dimensional bar code symbols? Because, when read, it is only the width of the bars and spaces that is taken into account — the height of the bars is only to give the symbol some built- in redundancy. Typical bar code symbols, therefore, are only read in one dimension.

One other important aspect of one- dimensional bar code symbols is that they seldom represent more than a dozen characters. Therefore, the bar code does not contain any data, per se. Rather, the bar code represents the key to a record in a database, where related information is stored. The best example is a car license plate which, by itself, doesn’t mean much but, when entered into a motor vehicle database, can access all sorts of information regarding the car it is attached to.

In the Two- dimensional (2-D) symbols, data are encoded in both the height and width of the symbol, and the amount of data that can be contained in a single symbol is significantly greater than that stored in a one-dimensional symbol. In fact, over thousands alphanumeric characters can potentially be placed in a single symbol the size of a large postage stamp! Obviously, the main advantage of using 2D bar codes is that possibly a large amount of easily- and accurately- read data can " ride" with the item to which it is attached. There are new applications being created for 2D bar code technology every day.

One of the amazing (and beneficial) aspects of two- dimensional symbols is their potential durability. To sabotage the readability of a conventional 1D symbol, one only has to add another bar to the beginning or end of the symbol or draw a line through the symbol, parallel to the stripes. This throws off the checks and a balance built into the decoding algorithms of a 1D bar code decoder and makes the symbol unreadable. By comparison, many degrees of redundancy can be built into a 2D symbol. While it makes the symbol somewhat larger, the remaining symbol is remarkably secure. We have experimented with vandalizing 2D symbols with holes, black marker and tearing. The symbol has remained readable through all of this abuse!

About PDF417

It's PDF417. PDF stands for “ Portable Data File.” A two- dimensional symbology, a single PDF417 symbol carries up to 1.1 kilobytes of machine- readable data in a space no larger than a standard bar code. And, unlike traditional one- dimensional bar codes, which depend on real- time links to a larger database, PDF417 symbols are the database. PDF417 symbols travel on paper. Moreover, PDF417 is recognized as the standard between two-dimensional symbologies by leading organizations worldwide.

In addition, PDF417 is an error- correcting symbology designed for real- world situations where portions of labels can get destroyed or damaged in handling. It performs error correction by making calculations, if necessary, to reconstruct undecoded or corrupted portions of the symbol.

Encoding data into a PDF417 bar code is a two- step process. First, data is converted into codeword values of 0 - 928, which represent the data. This is “ high- level encoding.” Then the values are physically represented by particular bar/ space patterns, which is “ low- level encoding.” Decoding is the reverse process.

At first glance, a PDF417 symbol looks like a set of stacked bar codes. When we look closer to analyze how the symbol is put together, there are several key elements. Those will be explaining below.

Bars and Spaces

All bar codes are comprised of bars and spaces (dark and light regions). A bar is a continuous dark area; a space is a continuous light area. From here on, we will refer to bar and/ or space as simply bar. Most bar codes have a fixed number of possible bar widths. That is, each and every bar must be one of a fixed number of sizes. Each bar's width must also be a multiple of the smallest bar width. For instance, if the narrowest bar is 10 mil, then possible bar widths can be 10 mil, 20 mil, 30 mil, 40 mil, etc... But not, 15mil, or 25mil since these sizes are not multiples of the narrowest bar size of 10 mil. ( mil, stands of thousands of an inch).

X Dimension

The width of the smallest bar is defined as a bar code's ' X' dimension. Each X' dimension is sometimes referred to as a module. In the following picture, you can easily pick out the smallest, or narrowest bar. By measuring this bar, we can determine the bar codes ' X' dimension. You can also see that all of the other bar widths is multiples of the smallest bar or ' X' dimension. Each bar's width is often expressed relative to the ' X' dimension; for instance, 3X refers to a bar that is 3times as wide as the narrowest bar.

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The following picture is a PDF417 bar code that looks like it is printed on graph paper. This image makes it easier to count the number of ' X' dimensions, or modules in each bar. If we look closely, we will see that each and every bar is an exact multiple of the minimum bar width. The first bar is 8X wide, the following space 1X wide, etc... In a validly printed code, without ink spread, you should never see a bar that is 1.5X, 4.2X, or not a whole multiple of X. In a PDF417 symbol, you will always see 1X, 2X, 3X, 4X, 5X, 6X, 7X, or 8X bars. Keep this in mind, you will see later how to detect, and avoid printing problems related to this topic.

Start / Stop Patterns

Every bar code has a start pattern on the left, and a stop pattern on the right. These patterns are unique for each type of bar code. PDF417' s unique start and stop patterns are:

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Codewords

In a PDF417 bar code, each bar and space does not store data. Data is actually stored in codewords. A codeword is a consecutive sequence of 4 bars and 4 spaces totaling 17X wide. The 417 in PDF417 refer to this codeword structure. Codewords reside between the start pattern on the left, and the stop pattern on the right. This region contains several types of codewords including data codewords, control codewords, and row indicator codewords. Each of these codewords abides by the rules described above. The picture below points out a single PDF417 codeword:

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Data Codeword Region

User data is first encoded into codeword values. These codeword values are then converted into physical codewords represented by bars and spaces as described above. Data codewords are physically located between the left and right row indicator codewords. Below, you can see the Data Codeword Region:

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Rows

If you look closely at a PDF417 symbol, you will notice that it appears to be made of many " 1D- like" bar codes. In reality, it is made up of multiple rows. A PDF417 bar code can have anywhere from 3 to 90 rows. This allows a PDF417 symbol to be reshaped by adjusting the number of rows. The following PDF417 symbol has 5 rows:

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Columns

A PDF417 symbol is made up of multiple data columns, which are sometimes referred to as the data column area. The number of data columns can vary from 3 to 30, to accommodate user's real estate requirements. These columns contain encoded data, as well as error correction information. Within the data column area, a single PDF417 can contain no more than 928 codewords. An example of a 3 column PDF417 symbol appears below:

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Error Correction

The PDF417 symbology has error correction capability. This capability enables scanners to read the bar code even if it has been torn, written on, or damaged in other ways. How much damage a symbol can withstand depends on the amount of error correction in each PDF417 symbol. The user has the ability to select 1 of 9 error correction levels for each symbol printed. Error correction is specified by selecting a level from 0 to 8. At level 0, a damaged PDF417 cannot be read, but the damage can be detected. At levels 1 through 8, a PDF417 symbol can still be read, even when damaged. As the error correction level increases, more damage can occur to the symbol and still be read. Consequently, the higher the error correction level, the larger the symbol becomes, while the data capacity goes down. The following table illustrates these facts:

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Error Correction Capacity

PDF417 symbols can be damaged and still decoded. The amount of damage that a symbol can withstand is its error correction capacity. For example, at level 5-error correction, 64 codewords of error correction are used. At this level, 31 codewords can have errors, while still being read correctly. If more than 31 errors exist, the symbol is unreadable.

X and Y Dimensions

The X dimension is the width of the narrowest bar in a printed codeword. The Y dimension is the height of each row within the PDF417 symbol. PDF417 is usually printed with an X to Y ratio from 1: 2 to 1: 5. By changing the X to Y ratio to 1: 2 or 1: 3, a significant amount of space can be saved.

Row and Column Limits

The number of rows and columns can be selected to place the symbol in a specific form. The PDF417 symbol is limited to 30 columns and 90 rows. When selecting columns, keep in mind that you are only selecting the number of data columns in the symbol. The normal PDF417 symbol has two row start columns and two row stop columns. Truncated PDF417 contains only two row start columns.

Truncated PDF417

A truncated PDF417 symbol is more area efficient than normal PDF417. By selecting this option, the right hand side of the symbol is removed or " truncated". This option should only be used in clean environments, since it is less immune to damage.

Compaction Modes and Amount of Data Encoded

We recommend limiting the amount of data encoded in 2D symbols to 1700 characters if possible. Although the AIM PDF417 specifications state that " up to 1100 bytes or 1800 ASCII characters can be encoded in a PDF417 symbol", we have found that these numbers are not realistic. The amount of data that can be encoded will vary depending upon the type of data, the compaction type, the error correction level chosen and what your scanner can read. In text compaction mode, the amount of compaction varies due to mode switching between different types of characters, such as between numbers, upper case, lower case and punctuation.

Because each codeword represents 1 of 929 possible values, data can be compacted into the codewords to save space. PDF417 has three data compaction modes: byte, text and numeric. Byte compaction encodes actual bytes of data, text mode encodes most characters on the US keyboard and numeric compaction encodes only numbers. The chart below shows more details about these modes.

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PDF417 translates into productivity

PDF417 technology translates into productivity. Easy to use and easy to integrate, a PDF417 application delivers the benefits of digital data communications with the simplicity of bar coding. It's very low in cost… printable in various sizes on a wide variety of media using traditional printing technologies…easy to support…and highly robust in its error correction capabilities. Moreover, PDF417 has been recognized as the standard among two-dimensional symbologies by leading organizations worldwide.

PDF417: Much More than Meets the Eye

PDF417 answers the need to capture, store and transfer large amounts of data inexpensively. It can exchange complete data files (such as text, numerics or binary) and encode graphics, fingerprints, shipping manifests, electronic data interchange (EDI) messages, equipment calibration instructions and much more. It provides a powerful communications capability – without the need to access an external database. And, for virtually no incremental cost, you can add a PDF symbol to the documents and labels you are already printing.

Think of PDF as an independent database with complete freedom of movement, traveling together with a person or on an item, object, package, form, document, card or label. It does what wired networks can't: allows you to immediately access your data regardless of location. Plus, encryption is available as an option when additional security is required.

Moreover, because PDF417 is a machine-readable method of transporting data, it eliminates time-consuming and error-prone manual data entry. It functions as a paper-based computer memory that can be written once and read over and over again. And, as a universal machine language, it communicates with all host operating systems. PDF417 encodes full ASCII, numeric or binary data and it uses sophisticated error correction algorithms to keep intact 100 percent of the data – even when as much as half the symbol is damaged. And it's self-verifying, so data errors can be detected and data integrity maintained.

What a Difference a Dimension Makes

One-dimensional bar codes contain an access code that serves as a real-time key for opening a database. A PDF417 symbol contains a complete data record and requires no access to an external database. Data, text, graphics, biometrics and voice records are immediately applied to the application transaction by simply scanning the symbol.

A Technology You Can Trust

PDF417 is the de facto standard 2-D symbology. In addition to its performance capabilities and application value in a wide range of industries, PDF417 technology is in the public domain–placed there by Symbol–and it conforms to industry and international "open" standards. For all of these reasons, PDF417 is emerging as the standard 2-D symbology by leading standards-setting organizations:

• The American National Standards Institute (ANSI) has just published a new 2-D standard: ANSI MH 10.8.3M unit loads and transport packages for two-dimensional symbols. It recommends the use of PDF417 for all shipping, receiving and supporting EDI documentation. Most standards associations will use this ANSI standard as the basis for their specific industry's application specification.

• AIM USA and AIM Europe, accredited ANSI standards-developing organizations, which have approved and published PDF417 as a Uniform Symbology Specification (USS) standard.

• The U.S. Department of Defense, which has designated PDF417 as the standard 2-D bar code for logistics applications and EDI formatting on paper labels.

• The American Association of Motor Vehicle Administrators (AAMVA), which has approved and published PDF417 for a broad range of driver and motor vehicle applications.

• The Automotive Industry Action Group (AIAG) 2-D Applications Committee, which has selected PDF417 for its key 2-D production and logistics applications, is completing their B-10 standard for shipping and receiving.

• The Telecommunication Industry Forum (TCIF) is reviewing PDF417 as the 2-D standard for product marking.

In addition, the U.S. Department of Defense, Office of Personnel and Readiness, has issued millions of military identification cards with PDF417 symbols for use on a global basis.

Verified in Independent Testing

Not only is PDF417 technology hard at work in a wide range of important applications, it has also been proven in independent testing. In reliability testing by the Ohio University Center for Automatic Identification, 32 million PDF417 characters were read without an error. Tests at the University of Pittsburgh proved PDF417 compatibility in high-speed overhead scanning and its readability even when symbols were damaged.

Technology that's Proven in Diverse Applications

Just about everyone in the private and public sectors is in the business of information, communication, identification and data management. PDF417 symbology serves all of these needs and has been proven in a highly diverse range of end user applications.

PDF: Expanding on Your Bar Code Capabilities

The two-dimensional benefits of PDF417 symbols are ideal for applications that are limited by the natural constraints of 1-D bar codes. The amounts of data needed as well as the environment it exists in are key deciding factors when choosing to implement a system using 2-D symbols. A single scan of a PDF417 symbol can easily replace multiple 1-D bar codes while delivering more information more quickly.

QUALITY CONTROL AND VERIFICATION

Barcode verifiers are primarily used by businesses that print and use barcodes. Any trading partner in the supply chain can test barcode quality. It is important to "grade" a barcode to ensure that any reader in the supply chain can successfully interpret a bar code with a low error rate. Retailers levy large penalties for non-compliant barcodes.

Barcode verifiers work like a reader, but instead of simply decoding a barcode, a verifier performs a series of eight tests. Each test is graded from 0.0 to 4.0 (F to A). The lowest of the 8 grades is the scan grade. For most applications a 2.5 (C) is the minimum acceptable grade.

Compared with a reader, a verifier measures a barcode. The measurement must be repeatable and consistent. Doing so requires constant conditions such as distance, illumination angle, sensor angle and verifier aperture. In comparison, a reader must interpret a barcode as reliably as possible over a wide range of conditions.

Barcode verifier standards

• Barcode verifiers should comply with the ISO/IEC 15426-1 (linear) or ISO/IEC 15426-2 (2D).

• This standard defines the measuring accuracy of a bar code verifier.

• The current international barcode quality specification is ISO/IEC 15416 (linear) and ISO/IEC 15415 (2D). The European Standard EN 1635 has been withdrawn and replaced by ISO/IEC 15416. The original U.S. barcode quality specification was ANSI X3.182. (UPCs used in the US—ANSI/UCC5).

• This standard defines the quality requirements for barcodes and Matrix Codes (also called Optical Codes).

• As of 2011 the ISO workgroup JTC1 SC31 was developing a DPM quality standard: ISO/IEC TR 29158.[16]

• International standards are available from the International Organisation for Standardization (ISO).

• These standards are also available from local/national standardization organizations, such as ANSI, BSI, DIN, NEN and others.

CHOOSING THE BEST BARCODE TYPE FOR PRINTING

Once it is determined which product to use for the printing of barcodes, the following suggestions may help in selecting the barcode symbology:

When using Barcode Components or Applications for printing, the following is suggested:

• When encoding uppercase and/or lowercase letters, numbers, punctuation, any letter or symbol appearing on the standard U.S. keyboard and lower ASCII functions such as returns and tabs, up to about 40 digits, use Code128. All of IDAutomation's barcode components and applications support Code 128 as the default barcode type.

• When encoding several lines of data of any type over 40 characters, it is suggested to use the PDF417 or Data Matrix barcodes.

When using Barcode Fonts, the following is suggested:

• When encoding only numbers, up to about 30 digits, choose Codabar Barcode Fonts. Codabar is the most dense, self-checking (easy-to-use) symbology.

• When encoding uppercase letters, numbers and these symbols (- . $ / + %), up to about 20 digits, choose Code 39 Barcode Fonts. Code 39 is also a dense self-checking (easy-to-use) alpha-numeric symbology.

• When it is necessary to encode uppercase and lowercase letters, numbers, punctuation and ASCII functions such as returns and tabs, up to about 40 digits, use Code 128 Barcode Fonts or the Universal Barcode Fonts.

• When encoding any data of any type over 40 characters, use the PDF417 or Data Matrix barcodes.

When barcodes are sent via fax machine or are used in a low-resolution environment, the following is suggested:

• After evaluating several popular barcodes, the Data Matrix barcode is the most dependable in a faxing environment. Data Matrix is one of the smallest and most dependable barcode symbologies. Compared to other barcode types, Data Matrix is approximately 30 times smaller than a Code 39 barcode representing the same data. This comparison may be seen visually in the Barcode Symbology Evaluation and Test Sheet.

• If the DataMatrix barcode cannot be implemented, it is suggested to print the chosen barcode at the largest X Dimension (or size) as possible, which will usually allow the symbol to be read by a scanner.

• When printing to thermal 203 DPI printers, special care must be taken to create accurate barcodes. Several knowledge base articles exist for the proper use of thermal printers:

▪ Printing to 203 dpi thermal printers with Barcode Fonts

▪ Using low resolution printers with Web Products

When Barcode Applications are used, the following is suggested:

• To create barcode images individually, save the images to a file or easily paste barcodes into other Windows applications, consider IDAutomation's Barcode Image Generator. This application is commonly used to create barcode image files for PhotoShop, Paint Shop Pro, Quark, CorelDraw, Word and other word processor and graphic applications where a single image can be printed several times without change.

• To print barcode labels dynamically from a database or list with a label design application compatible with Windows, consider IDAutomation's Barcode Label Software.

When encoding photos, arrays, binary data, Unicode, international or double-byte characters, the following is suggested:

A two-dimensional symbology (2D barcode) such as the PDF417 or Data Matrix barcode should be used to encode this type of data. 2D barcodes encode this type of data when the encoding mode is set to BASE256 or BINARY, which encodes all data, byte-by-byte. When scanning the data, the barcode scanner must be able to read all 256 bits of each byte. This usually means using the serial interface option (data bits have to be 8N) on the scanner, serial emulation over USB or another type of connection that allows all 256 bits of each byte to be transferred to the necessary application. Normally, keyboard wedge and USB barcode scanners (that emulate a keyboard) do not support extended characters above ASCII 128, and they only read characters that are actually on the keyboard. The scanner manual or vendor may need to be consulted for this type of implementation. Alternatively, the data may be converted to Base64 when encoded in the barcode and then back again when read. However, this requires additional programming and will create a symbol that is about four times larger then it would be with BASE256 or BINARY encoding.

When creating PDF documents, the following is suggested:

IDAutomation barcode fonts may be used to integrate barcodes into PDF documents, thus creating virus-free portable data files that can be viewed on all operating systems with a PDF viewer. The fonts have been tested and work with the following PDF conversion products:

• Adobe Distiller Server works well with all of IDAutomation's MICR, OCR and barcode fonts including symbol-encoded fonts.

• Crystal Reports version 9 and above can create PDF documents with IDAutomation's Barcode Fonts.

• PDFLib is a library for generating PDF "on the fly" for programmers only. Runs on Mac, Windows and several Unix platforms in addition to EBCDIC-based platforms, such as IBM eServer iSeries 400 and zSeries S/390. PDFlib is especially well-suited for generating PDF on a Web server. PDFlib can generate PDF data directly in memory (instead of on file), resulting in better performance and avoiding the need for temporary files. This product was implemented by a client using IDAutomation's PostScript Interleaved 2 of 5 Barcode Fonts with Redhat Linux 6.2.

• PDF Machine is a simple print driver that permits the creation of a PDF document from any printable source. Version 6.2 supports printing the barcode font at small point sizes.

READING BARCODE

One of the most common tools for reading barcodes is the hand-held barcode scanner. The barcode scanners recommended and sold by IDAutomation all have built-in decoders that can read several different barcode symbologies. There are a few low-priced scanners on the market, but they require complicated decoders. In the long run, after ordering and programming a decoder, more time will be spent using the decoder than if ordering a scanner with a built-in decoder.

Most of the barcode scanners sold by IDAutomation receive their power from the PC keyboard or USB port so no external power supply is required. When a barcode is scanned, the data is sent to the PC as if typed on the keyboard. To learn more about scanning barcodes, review how to scan barcode data into applications.

Most barcode scanners can read common linear symbologies such as Code 39, UPC, EAN, Code 128 and Codabar by default. Some scanner manufacturers’ ship new barcode scanners with most symbologies disabled, therefore, if a particular barcode cannot be read, make sure it is enabled in the scanner's firmware. Not all scanners read barcodes that are printed at small X dimensions (the x dimension is the width of the narrow bar in the code,) so it is advisable to check the barcode scanner manual to make sure the scanner can read the small X dimensions.

The low-priced IDAutomation Plug 'n Play USB Barcode Scanner performs like a laser scanner and reads very small barcodes. Barcodes of 4 to 32 mils in size and up to 4.2" in width are easily read from a distance of 4 to 8 inches with this scanner.

Barcode Accuracy & Misreads

The accuracy and amount of misreads of several different barcode symbologies were evaluated in a study at Ohio University Center for Automatic Identification. Studies indicate that a well-trained data entry operator will usually make a data entry error once every 300 keystrokes. Therefore, implementing even the least accurate barcode symbology is a huge step forward to increasing production and reducing data entry errors.

|Barcode Type |Worst Case Accuracy |Best Case Accuracy |

|DataMatrix |1 error in 10.5 million |1 error in 612.9 million |

|PDF417 |1 error in 10.5 million |1 error in 612.4 million |

|Code 128 |1 error in 2.8million |1 error in 37 million |

|Code 39 |1 error in 1.7 million |1 error in 4.5 million |

|UPC |1 error in 394 thousand |1 error in 800 thousand |

BENEFITS

In point-of-sale management, barcode systems can provide detailed up-to-date information on the business, accelerating decisions and with more confidence. For example:

Fast-selling items can be identified quickly and automatically reordered.

Slow-selling items can be identified, preventing inventory build-up.

The effects of merchandising changes can be monitored, allowing fast-moving, more profitable items to occupy the best space,

Historical data can be used to predict seasonal fluctuations very accurately.

Items may be repriced on the shelf to reflect both sale prices and price increases.

This technology also enables the profiling of individual consumers, typically through a voluntary registration of discount cards. While pitched as a benefit to the consumer, this practice is considered to be potentially dangerous by privacy advocates.

Besides sales and inventory tracking, barcodes are very useful in logistics.

When a manufacturer packs a box for shipment, a Unique Identifying Number (UID) can be assigned to the box.

A database can link the UID to relevant information about the box; such as order number, items packed, qty packed, destination, etc.

The information can be transmitted through a communication system such as Electronic Data Interchange (EDI) so the retailer has the information about a shipment before it arrives.

Shipments that are sent to a Distribution Center (DC) are tracked before forwarding. When the shipment reaches its final destination, the UID gets scanned, so the store knows the shipment's source, contents, and cost.

SOME BARCODE IMAGES

| |[pic] |[pic] |

| |Shotcode |High capacity color barcode |

|[pic] | | |

|Codablock | | |

|[pic] | [pic] | |

|Datamatrix 2D |EZ code | |

| | |[pic] |

| | |PDF 417 |

Home Depot starts barcode shopping from smartphones

The Home Depot announced Tuesday it will roll out its first mobile barcode program in a national print campaign featuring Martha Steward Living kitchens. By taking a picture of a 2-D barcode known as a QR code, shoppers can instantly watch product videos, read product reviews and purchase items directly from their smartphones.

The do-it-yourself retail giant plans to use the QR codes both outside their stores in print and online as well as on shelves within stores.

[pic]All of your contact information can be store in scannable QR code.

"We know our customers are already using their mobile device to assist in the purchasing process, and now Home Depot is embracing this technology to more closely connect our stores and customers to our digital content," Tom Sweeney, senior director of online strategy for , said in a statement. The company will also use the codes to offer promotions and discounts on featured Home Depot products along with a one-button option to buy.

The QR code technology is provided by ScanBuy, a pioneer in the barcode field. Home Depot’s codes can be scanned using the ScanLife app and customers without a scanning app can download the ScanLife app at scan or they can text HDscan to 43588.

There are roughly 25 million people in the United States who already have barcode scanning technology from their mobile device and the number is growing rapidly, according to ScanBuy. All it takes is a phone with a camera and an Internet connection, but people with big-display, video-ready devices like the iPhone, HTC Evo 4 and ThunderBolt will get the bigger benefit from Home Depot.

Bar-code technology for documenting administration of large-volume intravenous solutions.

The failure to properly document dispensing, administration, charging, and crediting of large-volume plain i.v. solutions in a hospital, along with the potential for using bar-code technology to reduce documentation discrepancies, was investigated. Portable bar-code scanners and preprinted bar-code labels were employed to identify large-volume plain i.v. solutions administered on two selected nursing units of a 1000-bed, private, not-for-profit hospital. Inservice training sessions were conducted to instruct hospital personnel in the use of the scanning equipment. Comparisons of patient statements and medication administration records for large-volume plain i.v. solutions established the level of documentation errors in the study hospital. The causes of these errors were traced to three primary sources:

failure to document administration of a solution to a patient (38%),

failure to credit patients for i.v. solutions returned to the pharmacy (37%), and

administration of a solution to a patient other than the patient for whom the solution was dispensed (25%).

Accountability for large-volume plain i.v. solution charges to patients was improved by 19% using bar-code technology. The pharmacy manager desiring to employ bar-code technology should determine convenient methods for applying bar-code labels to solutions and for scanning the bar codes, as well as provide programming that can compensate for erroneous scans.

IMPORTANCE OF BARCODE TECHNOLOGY IN MANUFACTURING INDUSTRY

A large amount is involved in manufacturing and inventory management. In this there is no waiting time. Manufacturers should have the system tools to manage the inventory and coordinate supply chain.

Using barcode system has greatly helped the manufacturing sector to achieve success by improving the efficiency, quality and delivery in their business. Barcodes and barcode labels are used as tools in the efficient and error free tracking of manufacturing inputs or raw materials and product identification.

Barcodes labels are important to run the business in an efficient way. There are different uses of barcode technology in manufacturing industry. Barcodes are read by barcode scanners. Barcode scanners, printers and labels all come under barcode technology.

Usage of barcode technology helps in reducing manufacturing costs and increases profits. Barcodes also help the regulatory authorities to find out the fakes or counterfeits. This system could not be successful without an accurate and efficient method of product identification, inventory management, delivery tracking.

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