Subject Re: [IBO] OT: Barcode Recognition Components
Author Lester Caine
> We have a high speed flatbed scanner scanning delivery docs printed out by
> my app, as such i can print any type of barcode on the document. What i
> need is something that i can pass a bitmap, jpg, etc to that will scan the
> image for any barcode and return the data read.

I run that sort of stuff out via FastReport, but they only
get used with hand scanners in the distribution chain :)
So you know 'where' the barcode should be, and can capture
that area on the 'return' scan, and then process it.

> The documents can be a bit dirty but are generally good quality.

This can be a problem in use, however since you have a two
dimentional bitmap, you can 'compress' the data vertically,
and build a single line, ignoring the 'holes' and 'marks'.
If the majority of the vertical pixel line is white, output
is white, if the majority is black ... This also takes care
of a slightly twisted scan. The you just need to 'run length
code' the resulting line and you have the 'barcode' and can
decode it based on the format you used to create it.

The only dificult bit is ensuring that the barcode is in a
location that you can allow for 'lax' placment on the
scanner. i.e. allow a largish border around it.

I have to admit to cheating in a few places, just using wide
and narrow bars for 1 and 0 and droping a 24 bit number on
the page - crude but quite efficient when you 'scan' using a
slide through scanner rather than flat bed.

The only package I did find ( other than complete OCR apps )
but I have not found out an actual price for it, as I have
been cheating and using ABBYY FineReader that comes with the
flatbed scanners we have been using - the barcode bit of
that comes at a price, so I just use a large font and numbers ;)

Lester Caine
L.S.Caine Electronic Services