Technical Information
Barcode properties
text property the text text property represents the barcode data in a human readable format 2d barcodes (pdf417, qr, datamatrix) may contain both textual data in various languages as well as binary data to recover the most accurate and relevant barcode values from the barcode in the text property clearimage readers employ a combination of several techniques detect eci and unicode indicators to derive the language specific text make xml data stored in the barcode more readable with the appropriate level of indentation present the data from driver licenses and id cards cards in a uniform xml format decompress data that was previously compressed by adobe® livecycle® ( trademarks of adobe systems incorporated) data property the data data property returns a byte array with the original, unprocessed binary data stored in the barcode as with any binary file, the application must be aware of the stored data format to properly interpret the data structured append / macro pdf417 structured append (or sa ) mode is a special mode defined by pdf417, datamatrix, and qr standards to encode a large amount of text or binary data into multiple barcodes ( sa segments ) in pdf417 standard, this mode is called macro pdf417 clearimage processes sa segments according to the corresponding standards and aim eci standards https //aimglobal site ym com/store/viewproduct aspx?id=1413330\&hhsearchterms=%22extended+and+channel+and+interpretations in buffered and unbuffered modes buffered mode in buffered mode a single barcode value reconstructed from multiple consecutive sa segments barcode’s metadata contains details about individual sa segment information note if not all sa segments are present or some segments failed to read, then a partial barcode value is reconstructed from consecutive sa segments to obtain barcode values in buffered mode com and java api use find(0) find(0) method read barcodes on a page net api set barcodereader maxbarcodes = 0 barcodereader maxbarcodes = 0 (note zero is a default value no need to initialize explicitly) use barcodereader read (filename, page) barcodereader read (filename, page) to reconstruct sa value from the sa segments on a single page use barcodereader read (filename) barcodereader read (filename) to reconstruct sa value from the sa segments on all pages in a file unbuffered mode in unbuffered mode each sa segment’s barcode value is returned separately as required by standards, both text and data properties start with the following symbology identifier 3 characters sequence starting with ] character macro control block sequence starting with \mi and ending \my barcodes’s metadata contains the sa information for this segment note each segment is decoded separately therefore eci encoding that starts in a previous segment would not be applied to the current segment to obtain barcode values in unbuffered mode com and java api use firstbarcode () firstbarcode () / nextbarcode () nextbarcode () methods use find (maxbarcodes) find (maxbarcodes) where maxbarcodes is not 0 net api set barcodereader maxbarcodes = n; barcodereader maxbarcodes = n; where n > 0 use one of the barcodereader read (…) method metadata metadata is the information in xml format that describes various properties of barcode, such as pdf417 rows/columns/ecc level, language specific code pages, eci codes, and structured append information to obtain metadata string smeta = obarcode decode((barcodedecoding)102);std wstring wsmeta = objcibarcode >getinfo(l"meta"); other barcode properties other elements of the information associated with the barcode are available to the user application property description type type barcode symbology this value is typically used to filter the barcode of interest when multiple barcodes are present on a page or in the file length length a number of bytes representing barcode value in data data property rectangle rectangle location of barcode on a page this value is typically used to filter barcodes of interest when multiple barcodes are present on a page rotation rotation barcode rotation is relative to the page image this value may identify page scanning orientation for example, if you know that the barcode is printed horizontally on the page, then an “upside down” barcode rotation indicates that the page was scanned upside down you can use the clearimage rotate rotate method to correct the image topleft topleft , topright topright , bottomleft bottomleft , bottomright bottomright location of barcode corners on a page modulesize modulesize average width (in pixels) of the barcode modules this value is important for tuning the barcode creation and scanning process to optimize performance, it is recommended that for 1d barcodes and pdf417, this value be in the range of 3 to 10 pixels, while for datamatrix and qr, from 5 to 15 pixels file file name of the file containing barcode ( net api only) page page page number containing barcode ( net api only)