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Devote a small section of printed railway timetables to 2d barcodes, which hold the same information as the printed timetable.
Passengers could then photograph the timetable on their mobile phone, which would detect the bardcode, decode it and place into your calendar program.
Included a link to
show an example 2d bar codes.
Commerical product using 2d barcodes
http://www.cognex.c...ions/id/default.asp
[monojohnny, Jul 27 2006]
Wikipedia Info
http://en.wikipedia.org/wiki/Barcode
[monojohnny, Jul 27 2006]
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Annotation:
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I was thinking OCR software wouldn't be as reliable as reading from the barcode... |
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The information density of a 2D barcode can be much greater than that of text. With suitable software, a half-megapixel (640x480) camera photographing a really big 2D barcode could reliably capture more than 4Kbytes of usable data--possibly 8Kbytes or more (16K would probably be achievable, though image compression would be a no-no). Getting even 4K worth of data using OCR, assuming 6 bits per character, would mean each character would be represented by about 64 pixels. Not a problem if the camera is perfectly aligned, but if anything isn't perfect OCR under such cases will be difficult at best. |
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Incidentally, many newer barcode readers--including 2D readers for anything but PDF-814 format--don't use lasers except as an indicator for the user for where to place the barcode to be scanned. PDF-814 is designed so that a scanner can read bits and pieces and assemble them all together; its information density is reduced considerably by that feature. Modern scanners use a CCD camera to photograph an entire barcode at once and then use some digital magic to determine whether there's an interesting-looking barcode in the picture. |
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Sounds reminiscent of VCR-Plus, in which some sequence of digits translated into a start time, end time and channel number. I assume these bar codes translate into a departure time and place, arrival time and place. Is this translation via an algorithm (preferred?) or a database? |
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