Comment by sam1714
3 hours ago
It's not as complicated as it seems from a technical perspective. Stamps have been UV-tagged since the 1960s as an anti-counterfeiting/automated detection measure. In the analog era, you shine UV light on a letter and if it it glows enough, it's got a stamp.
Modern processing machines (AFCS) capture both a visible and UV image of the mailpiece, so it's fundamentally changing the image processing software to have it look for the barcode on the UV side if it can't find one on visible. The downstream DBCS sorters already read secondary barcodes that are applied by the AFCS which happen to be in UV ink.
Further, USPS benefits from the same idea to hide a barcode for marketing (junk) mail. When combined with a handwriting-like typeface, it makes letters look personal and gets people to open them more. Same psychology where mailers apply a bulk-rate stamp instead of using a permit imprint.
It's a very Steve Jobs/Apple case where it sounds like a minor detail that requires crazy advances, but under the covers, it's very technically feasible, and importantly, can exploit economies of scale.
What’s the latest on the roomful of people who read nearly-impossible-to-read addresses? Was dwindling last I heard—mad respect to them. You see some of those envelopes, complete chickenscratch or water damage, and somehow they get them to their destination.
In the 50s, when they started to use machines to sort mail, there were keyers at every facility that sorted mail. I believe there are still are still some local keyers on parcel sorters, where it's harder to "lift" the image of the address on a large box.
For letter encoding, they used to have 55 centers, in 2014 it became one, in Utah. A large part of it is OCR getting better and deciphering most handwritten addresses.
Another part of it is simple consolidation: it's trivial to send images over networks, and due to how mail has to be sorted together for dispatch, the demand tended to be peaky. Consolidation lets you exploit different timezones. (Slowing down the mail also gives a big benefit because you can spread the load over the whole day)