Talk:OneCode

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[edit] Illustration

An example would be very informative. -- Beland 15:52, 21 June 2007 (UTC)

It is true that examples might prove very informative. However, having downloaded and taken a look at the PDF of the technical specifications of it, any example would honestly be fairly difficult to understand, other than generally identifying what one of these codes looks like. There are a lot of bitwise operations that go on, as well as a CRC that is generated. There are lookup tables which translate bit patterns to character codes. The CRC is "applied" to the barcode by bitwise taking the CRC and either keeping (CRC bit is a 0) or bitwise inverting (CRC bit is a 1) the string that goes into formulating the barcode. At least with PostNET, it's easy to see the transformation from a digit string to a 2-of-5 bit code from weights of 7, 4, 2, 1, and 0.

To describe overall what it looks like, I'd have to say something like this:

The "four state" concept comes from the idea of some base bar height and (X, Y) position (call it a 0 representation), then a bar is extended either above, below, or both above and below the X axis. In the literature, they call the "zero" bar a "tracker," as it helps to track the progress of a scanner proceeding in the +X direction. Then they talk about "ascender" (+Y), "descender" (-Y), and "full" (both + and - Y) bars.

Under the PostNET Wikipedia entry, you can get an idea of the approximate look of the bars; they figured out some UTF-8 (I think) characters that look like a PostNET code. Imagine instead the long and short bars on that page being centered vertically, but then some bars align on the tops and others align on the bottoms.

Joe 22:49, 3 September 2007 (UTC)

[edit] Name

According to USPS-B-3200E specification,

“

1.1. Scope of the Intelligent Mail® Barcode – This specification covers the Intelligent Mail® barcode used in the USPS mailstream. It is also known as the USPS OneCode Solution or USPS 4-State Customer Barcode (abbreviated 4CB, 4-CB, or USPS4CB).

”

So OneCode and IMB are actually one and the same thing.