How to identify whether UPC-E or EAN-8

[vaughnd(Legacy Member)]

Hi, I'm struggling with recognising whether a barcode is UPC-E or EAN-8 in software I'm writing in South Africa.

I receive barcodes in many different formats from a number of files and need to reduce them to their basic form without check digits, i.e.
00000000123013 => 123013
01230137 => 123013

00000000565121 => 565121
05651214 => 565121

00000002201029 => 220102

00000002200321 => 220032
02200321 => 220032

All of these work fine, and I think they're UPC-E, but the one below has a check digit of 4 so I end up with 1000931 instead of 100093 as I should. I think it's because it isn't a proper UPC-E barcode, but even if it's a EAN-8 they must be adding a bad check digit?

00000001000931 => 100093
01000931 => 100093

Any help or pointers on recognising bad barcodes or identifiying whether a barcode is EAN-8 or UPC-E will be appreciated.

Vaughn

[glitch (legacy member)]

There is no conversion from EAN-13 to EAN-8. It is likely that the number is a UPC-E with wrong checksum.

http://www.morovia.com/education/symbology/ean-8.asp