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0 pointsmoremetadata3y ago0 comments

> It looks like it went through the automated letter sorter, too

I understand the mail sorting depots can x-ray scan and read the contents of letters up to 4 pages of a4 folded, but that could have been hackers feeding me fake info in order to stop me writing letters.

An example of the technique https://www.theguardian.com/books/2021/mar/02/researchers-re...

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jcrawfordor3y ago

I'm not aware of any postal service that uses a method other then optical imaging for address reading. Further, in some countries such as the US, it is not legal for the postal service to "look inside" mail pieces without a warrant.

While this type of 3D X-Ray technique is indeed possible it requires expensive specialized equipment and a great deal of effort, thus it being a major achievement for this university group. Or in other words, if a research group puts out a press release lauding a first, it is not likely to be a technology in use in thousands of sorting centers for millions of mail pieces daily.

tialaramex3y ago

The Royal Mail in the UK is definitely allowed to open mail as a last resort to figure out where it should be returned to, the National Returns Centre undertakes this work. If the contents turn out to be something that isn't returned (e.g. a newspaper or magazine) it's destroyed, if it's a letter the NRC will try to figure out where it came from and send it back there.

Most commercial mail carries an return address written on the reverse to avoid the need for this, and of course letters you write by hand should also provide a return address in principle although you're much less likely to send stuff to the wrong address than a commercial operation - when I heard my cousin had moved just before Xmas I didn't send her a card, because there's no point sending it to the wrong place and hoping it gets forwarded eventually, it's just an Xmas card.

moremetadataOP3y ago

> I'm not aware of any postal service that uses a method other then optical imaging for address reading. Further, in some countries such as the US, it is not legal for the postal service to "look inside" mail pieces without a warrant.

It could be hackers exploiting my lack of knowledge to social engineer me for their own criminal gain then. They even mentioned some of the old postal machines were for sale on ebay.co.uk, so when I looked there were 2nd hand postal xray machines for sale.

jcrawfordor3y ago

X-ray is not that unusual to check for contraband at customs, although it depends on the country whether or not it is a routine practice or requires suspicion. Perhaps the UK does so on domestic mail as well but that would be surprising to me, it's pretty high cost to do at large volume. These X-ray machines are the same type used at airports and usually produce either a synthetic isometric 3D-type image or two 2D images at 90 degree offset. The resolution and sensitivity are both nowhere near high enough to read text on documents, they're primarily oriented at recognizing firearms and very dense objects typical of drug smuggling. Much of the data modern X-ray parcel scanners produce is synthetic as well, based on machine vision and multi-exposure methods, so the display tends to suggest that the data they collect is of higher resolution than it actually is.

You would struggle to determine whether a page is folded A4 or A8 with one of these machines, reading text is far beyond their capabilities.

Symbiote3y ago

There's a difference between spotting a bomb in a parcel and reading the instruction manual.

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jcrawfordor3y ago

tialaramex3y ago

moremetadataOP3y ago

jcrawfordor3y ago

You would struggle to determine whether a page is folded A4 or A8 with one of these machines, reading text is far beyond their capabilities.

Symbiote3y ago

There's a difference between spotting a bomb in a parcel and reading the instruction manual.

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j / k navigate · click thread line to collapse