Supported Bar Code TypesWhen designing a Capture system that employs special bar code features, ensure that all parts of the system — from the scanner to the storage repository — can support the features adequately.
Consider the following to ensure adequate support by Capture:
• Your scanner, scanner interface card, or doc processing software might support bar code types that are not listed in this document. Conversely, your scanner might not support some of the bar code types supported by Capture.
• Some bar code types supported by Capture might provide features (support for control
characters, for example) that are not supported in other Capture components.
• Some bar code types might contain more characters than Capture features (such as index fields) can accommodate. For example, some wo-dimensional bar code symbols support up to 2000 characters in a single bar code. However, your index fields, configured on the server, might not be able to accept that number of characters and truncate the data.
NOTE FileNet added support for two-dimensional bar codes in Capture release 4.0. If you are using an earlier release, you must upgrade to Capture 4.0 to use the two-dimensional bar codes.
General ConsiderationsUsing bar codes for quality assurance, batch separation, and automatic indexing can reduce cost, increase system throughput, and reduce errors. A bar code contains information – account numbers, part numbers, customer addresses, etc. - that usually corresponds to properties that are associated with the documents you are scanning.
When using bar codes, you need to determine if you are using hardware or software bar code processing. If your scanner or scanner interface board supports doc processing, you use hardware bar code processing. Hardware bar code detection takes place as you scan your documents. The scanner passes the image to the processor on the board that interprets the bar code based on configuration settings in the Scan component. The interpreted information is stored as properties of the image.
If you have optional Doc Processing (Kofax Adrenaline) software installed you use software bar code processing. This processing is performed by the DocProcessing component. Software bar code processing takes place as a separate step, after you have scanned or imported your document. Software bar code processing locates the bar code in the image and extracts the embedded information. You configure the bar code settings for post-scan software bar code detection through the DocProcessing component.
Specific characteristics of bar codes include height, width, ratio, bar code length (minimum chars per bar code setting), max bar codes per line, max bar codes per page, search direction, bar code type, quality, edge noise, quiet zone, speckling, and skew. All of these characteristics can be adjusted to maximize bar code detection
There are a number of symbologies, or bar code alphabets, available. Each symbology varies in the number of characters contained in its alphabet. For example, Code 3 of 9 includes 43 characters including letters, digits and some punctuation.
Bar Code Quality AdjustmentsThe quality of the bar code on the page to be scanned (or imported) will affect whether or not the bar code can be read and decoded accurately. Both hardware and software bar code detection methods may fail if the bar codes on the original images are distorted or poorly reproduced. The following suggestions apply to the bar codes on the source documents that you are scanning or importing:
• The density of the lines of the bar code can be made darker or lighter to improve detection. Increase the resolution used to print the bar code to increase crispness of the bar code and hence the reading accuracy rate. A slight adjustment in dpi can make a significant difference. Please note that increasing the dpi resolution may also create noise. You must determine the best procedure for your unique conditions.
• Print the bar code directly onto a page.
• Never affix bar codes to a page using tape. Tape interferes with the scanner’s ability to detect the bar code.
• Larger bar codes are read more accurately and tolerate skew better
• Photocopies can show speckles that can interfere with bar code detection. Use a bar code that is printed with a laser printer to ensure a crisp copy. Improving Bar Code Reading Accuracy Adjusting your scanner can improve the success and accuracy of bar code detection. Check your scanner manual for tips to improve quality. The following conditions contribute to the accuracy reading rate and speed of detection of bar codes. By adjusting these parameters, you may control the accuracy and detection speed of bar codes.
Bar Code Height SettingThe Height setting is the distance between the top of the bar code and the bottom of the bar code. The minimum bar code height (of the entire bar code) is approximately 0.15 inch, and the maximum is 1.25 inch. However, a taller bar code has a better chance of being successfully read. By increasing the search height, the speed increases while reading accuracy decreases. By decreasing the search height, the speed decreases while the reading accuracy increases.
Bar Code Length SettingThe Bar Code Length is the minimum number of bar code characters that must be found before the bar code is processed. You specify the bar code length in the Min. Chars per bar code field. Bar Code Length applies to the following bar code types:
• Codabar
• Code 128
• Code 93
• Interleaved 2 of 5
• Code 39 (Code 3 of 9)
• Linear 2 of 5
A bar code is read more accurately and quickly if it has fewer characters. As the number of characters increases, there is a higher chance for error.
For example, a 3-character Code 3 of 9 bar code contains 50 elements, while a 10-character Code 3 of 9 bar code contains 120 elements. The 3-character Code 3 of 9 bar code has a higher probability of being read successfully and quickly. The following bar codes are fixed-length bar codes. Any value in the Min. chars per bar code field
is ignored.
• UPC-A
• UPC-E
• EAN
• Postnet
• Maxi code
Bar Codes with Thin Bars When the width of the smallest element is composed of 3 or less pixels, the detail may not be distinguished.
Width SettingThe Width is the physical width of the smallest element within the bar code. You can alter width settings slightly to work with other bar code settings. Adjust the width setting from a minimum of 0.010 inch to a maximum of 0.050 inch. Most bar code widths fall within the following ranges:
Because the larger elements of the bar code are calculated from the smallest using the ratio value. it may be necessary to adjust the ratio value as well.
Note that when the width of the smallest element is composed of 3 pixels or less, the detail may not be distinguishable. For the best accuracy rates, set the width of the barcode as close as possible to the actual width.
RatioRatio is the ratio of the sizes of the large elements to the small elements of the bar code. When the ratio is large, the bar code is easiest to read. The ideal ratio is 3:1, indicating that the width of the largest element is three times larger than the narrowest element. Because the bars in a bar code can lose pixels during the scan process, smaller ratio bar codes, such as 2:1, are harder to detect. When using the ratio setting, you must also consider the Width parameter.
For example, if the width of the narrowest bar is 0.020 inch, the width of the largest bars would be 0.040 for a 2:1 ratio or 0.060 for a 3:1 ratio. You must decide which ratio and bar code width would give you the desired result based on all your operating conditions.
By default, many bar code types use a ratio of 3:1. The option to select a ratio of 2:1 is available for some bar code types. The following bar code types can make use of the ratio setting:
• Codabar
• Code 39
• Code 93
• Linear 2 of 5
• Interleaved 2 of 5
Maximum Bar Codes per lineThe Maximum bar codes per line controls the maximum number of bar codes that appears along the same axis (row or column). The search continues along the same axis until the edge of the image is detected or the specified number of bar codes is encountered. The best performance is obtained when you use only one bar code per line, thus minimizing the duration of the search performed.
Maximum Bar Codes per pageThe Maximum bar codes per page should always be set to the number of bar codes that may actually appear on your documents. Because the scanner or software searches the entire page, the system slows down if you specify a large number of barcodes. You may use a maximum of 64 bar codes per page.
Search DirectionThe Search Direction determines which directions are used to search for bar codes. Select only the orientation directions that are required. With the minimum number of directions set, a faster search occurs because there are fewer directions to search. If you choose to search all four directions for bar codes, there is a large performance degradation.
Bar Code TypesThe Bar Code Type determines what type of bar code to search for. You can select more than one bar code type, but you should select only the bar code types that you actually use. The more bar code types you select, the longer it takes to process each page. Some bar code types are mutually incompatible, and you cannot select their types together. The incompatible combinations are:
• Interleaved 2 of 5 and Linear 2 of 5
• UPC-A and EAN
• UPC-A and UPC-E
• Postnet and any other type
QualityIf you are processing bar codes that are smooth and free of noise, set the Quality to Good. Bar codes that are of lesser quality require the Normal or Poor setting. The Quality setting and the Height setting determine the number of searches for bar codes that are made within an area or page. For instance, increasing the bar code height and a lower quality setting causes the bar code driver to perform more searches for bar codes. The following conditions also contribute to increasing the accuracy reading rate and speed of detection of bar codes:
Edge NoiseEdge noise describes bar codes containing bars that have rough edges. This occurs when the bars acquire or drop pixels, causing a blurred bar. If the ratio setting is small, and the elements gain or lose a pixel during scanning, the ratio setting may decrease further making the bar code difficult to read. It is best to minimize Edge Noise by improving the quality of the bar code image you are using, for instance by increasing print resolution (dpi) when you print bar codes.
Quiet ZonesA quiet zone is the area immediately preceding the start character and following the stop character, which should contain no marking. A bar code must be surrounded by a noise-free quiet zone of at least 1/10 inch; a 1/4 inch area is best. A quiet zone provides a period in which no lightto- dark or dark-to-light transitions occur, making it easy to differentiate a bar code from other information. Position bar codes away from the edge of an image, making sure there are no extraneous marks within the quiet zone. Clean quiet zones, also called margins, improve the readability of the bar code image.
SpecklingSpeckling refers to small pixels around the bar code region. This problem becomes serious when the pixels near a bar code interfere with the detection of quiet zones. Use the Despeckle function, if available, before you start searching for barcodes to eliminate extraneous pixels in the bar code area. You can also reduce the interference that is caused by debris on the scanner glass by cleaning it prior to scanning the bar code.
SkewEven though scanners are capable of reading skewed bar codes, there are more detection
problems with heavily skewed bar codes. It is best to apply the bar code to the page correctly. However, you may also apply the Deskew function, if available, before you start searching for bar codes.
Paper FeedEnsure that the page is feeding correctly into the scanner to minimize skewing. Also keep in mind that it takes longer to search along the longer side of a piece of paper for bar codes than to search the shorter side.
Using Bar Codes with FaxesIt is possible to process bar codes on inbound fax images using Capture. Note that the resolution and overall quality of the fax image must be very good. The originating and receiving fax machines must be configured carefully. Additionally, you must install DocProcessing on the receiving Capture workstation. You will need to try different settings when configuring your fax machine and Capture to ensure best results.
Fax Machine SettingsEnsure that the sensitivity of the sending fax machine is set on the most sensitive setting. For some fax machines, this may be called Details. For others, the designation may be Fine or Superfine.
Capture Bar Code SettingsBecause the faxed bar code is entered into Capture as a TIFF image, the DocProcessing
component is responsible for processing the bar code information. As a result, you must configure the bar code parameters in the Bar Code tab of the Doc Processing Properties dialog box. Set the Quality setting to Poor and make sure that the remaining settings for the bar code you are using are correct.
Using Bar Codes In CaptureIn Capture, bar codes can be used to optically acquire such information as account numbers,Invoice numbers, and dates. Bar codes can also be used to trigger events, in much the same way as patch codes are used.
Bar Code DatesData fields obtained from bar codes are stored as strings. You can use string selection in the Index component of Capture to change a string date collected from a bar code into a date field against which computations can be performed. When bar codes are used for auto indexing, the date mask format of the bar code must be the same as the format in the date field. When preparing bar codes for autoindexing, use bar code date formats that are supported by Capture, and consider using one of Capture’s four-digit year formats.
If a two-digit year format is used in a bar code, the century selected for the date field applies to the date. This is true whether the century is the default current century or the stated century. Capture cannot obtain the century from the scanned date since the scanned date is stored as a string, not a true date. To create bar codes from which dates can be read:
• Match the date formats of the bar codes to the formats supported in Capture.
• Use a four-digit year format in the bar code. This action will make sure that the Capture uses
the correct century.
Supported Bar CodesThe following examples of bar codes are for definition and clarification only. Note that these example bar codes are not to scale and are unsuitable to use as test samples.
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Standard (One-Dimensional) Bar Codes-----------------------------------------------
The following bar codes are supported in all Capture releases.
CodabarCodabar is a self-checking, variable-length bar code that can encode sixteen data characters (0 through 9, plus six special characters). Each character is represented by seven elements within the bar code (four bars and three intervening spaces). An intercharacter gap separates each character within the bar code. Codabar symbols can vary in length. Codabar is useful for encoding dollar quantities and mathematical figures.
Code 3 of 9 (39)Code 3 of 9 is an alphanumeric, self-checking, variable-length bar code that uses five black bars and four white bars to define a character. Three bars are wide and six are narrow. A character is represented by nine elements. An intercharacter gap separates each character. Start and stop characters are depicted as asterisks (*) and are used to delineate the bar code. The bar code is preceded and followed by quiet zones. A check character is optional. Code 3 of 9 supports 26 uppercase letters, 10 digits, and 7 special characters which include:
- . $ / + % (space)
Code 93Code 93 is a variable-length bar code that encodes 47 characters. Each character is composed of nine elements arranged into three bars with their adjacent spaces. Code 93 is a compressed version of Code 3 of 9.
Code 128Code 128 is an alphanumeric, high-density, compact, variable-length bar code that can encode the full 128-ASCII character set. Each data character is represented by six elements. There must be an even number of black elements and an odd number of white elements.
EANEAN is used for products that are required to be identified by their country of origin. It is a fixed length bar code that can encode 13 characters. The first two characters identify the country of origin, the next 10 are data characters, and the last character is the checksum. It is a superset of the UPC-A character set. EAN is incompatible with UPC-A.
Interleaved 2 of 5Interleaved 2 of 5 is a high-density, self-checking numeric bar code that uses five black bars and five white bars to define a character. Two digits are encoded in every character—one in the black bars and one in the white bars. Two of the black bars and two of the white bars are wide. The other bars are narrow. Each Interleaved 2 of 5 bar code must contain an even number of encoded digits and must be of a fixed length. A check character is optional.
-78/43
AA7777
PostnetPostnet is the Zip+4 postal bar code that is placed on envelopes or postcards to expedite delivery. Each code may consist of five, six, nine, or twelve digits plus a correction code. Note that the Postnet bar code is not compatible with other bar code types and there may be only one per page.
UPC-AUPC-A is a bar code that encodes a twelve-digit number. The first digit is the number system character. The next ten digits are data characters. The last digit is the checksum. This is the standard bar code used on merchandise to identify the product and manufacturer. UPC-A is incompatible with EAN.
UPC-EUPC-E is a bar code that is a zero-suppressed version of UPC-A. The data characters and checksum are compressed into six characters. The original ten data characters must have at least four zeros and the number system must be zero.
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