发明公开
EP0783160A3 A clock free two-dimensional barcode and method for printing and reading the same
失效
无时钟信号和用于印刷方法和读出码的二维条形码
- 专利标题: A clock free two-dimensional barcode and method for printing and reading the same
- 专利标题(中): 无时钟信号和用于印刷方法和读出码的二维条形码
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申请号: EP96308846.3申请日: 1996-12-05
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公开(公告)号: EP0783160A3公开(公告)日: 2001-07-11
- 发明人: Lopresti, Daniel , Esakov, Jeffrey , Zhou, Jiangying
- 申请人: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
- 申请人地址: 1006, Ohaza Kadoma Kadoma-shi, Osaka 571-8501 JP
- 专利权人: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
- 当前专利权人: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
- 当前专利权人地址: 1006, Ohaza Kadoma Kadoma-shi, Osaka 571-8501 JP
- 代理机构: Dixon, Donald Cossar
- 优先权: US569280 19951208
- 主分类号: G06K19/06
- IPC分类号: G06K19/06 ; G06K1/12 ; G06K7/14
摘要:
Inventive two-dimensional barcodes, each having encoded digital information in a bitmap (15) representing preferably randomized encoded data bits or pixels (17), are printed onto a printed medium (10-12). The bitmap (15) may further include a plurality of block identifiers (21-24), spaced a predetermined number of encoded data bits apart, which are used to make corrections for missing or added data bits when the barcode is decoded. Upon decoding a barcode printed on the printed media, the digital information is scanned and the number of horizontal (73,74) and vertical (75,76) edges in each respective column and row of the barcode are determined. An edge is determined by selecting a pixel and determining if the two pixels adjacent to the selected pixel are of different colors. After all of the edges are counted, selected groups of columns and rows are analyzed to determine local minimas in the number of counted horizontal and vertical edges in each selected group which provide the column and row center line for each selected group. Thereafter, the binary data located at the intersection of each column and row center line are read out to produce a signal representative of the encoded digital information in the printed barcode.
公开/授权文献
- EP0783160B1 Method for reading a clock free two-dimensional barcode 公开/授权日:2005-11-30
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