2335: Photo Deposit

Explain xkcd: It's 'cause you're dumb.
Jump to: navigation, search
Photo Deposit
It's okay, they scan the serial numbers and make sure you can't deposit the same bill more than once.
Title text: It's okay, they scan the serial numbers and make sure you can't deposit the same bill more than once.


Ambox notice.png This explanation may be incomplete or incorrect: Created by a BANKNOTE PHOTOCOPIER. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

Some mobile banking apps allow users to deposit checks through the app, by photographing the check and entering the relevant information. The comic parodies this imagining a bank that allowed you to "deposit" banknotes via a mobile app. The caption implies that this attempt is predictably disastrous, as it's shut down within six hours.

Checks are essentially documents instructing a bank to disburse funds from a given account to a specified recipient, hence electronic transfers make sense: the recipient's bank can transfer the image to the depositor's bank and the funds can be transferred between the two. The check could only be deposited by the recipient, and any attempt to deposit the check repeatedly would be refused (and potentially subject the recipient to legal action). By contrast, cash functions as a bearer instrument, where physical possession of the banknotes effectively constitutes possession of the funds. Hence, depositing cash electronically would make little sense, as the depositor would still have the notes (and therefore the money), and the bank would not. Such a transaction would enrich the depositor at the expense of the bank.

The title text states that the app recognizes the serial numbers on the bills and prevents users from depositing them multiple times. However, this would not solve the fundamental problem. Clients could still deposit all of their cash and retain ownership of it. And they could then exchange those bills for different ones and deposit the new bills, repeating the process indefinitely (which explains Cueball's comment about "a lucrative six hours"). It is possible that Megan and Cueball are deliberately depositing the same bills to each of their accounts, given their close proximity.

The only way such a system could work is if every entity that accepted cash payments or deposits operated from a common database, functioning in real-time, which kept track of each transaction, and disallowed any further use of that specific bill. This would have the ultimate impact of making cash virtually useless, as once every bill had been spent once, all future transactions would need to be electronic (unless there were a system in place to physically distribute the appropriate bills to the appropriate people, which would defeat the entire point). Such a system is essentially the basis for Cryptocurrency, which uses a crowd-sourced system to track the movement of money. But such a system would require virtually universal acceptance in a given country, and could not be implemented by a single bank.

In addition, the system would be highly vulnerable to counterfeiting. Common anti-counterfeiting measures include using distinctive materials and fine details, both of which are difficult to duplicate well enough to fool a human. Smartphone cameras, on the other hand, can't distinguish texture and may not have sufficient resolution to make out that level of detail. Counterfeiters could produce and deposit an almost unlimited number of bills, then destroy them, leaving little evidence of their crime.

As a result, this system would be inherently unworkable, and the party that would suffer from it would be the bank that implemented it in the first place. Which makes it realistic that, if a bank were to implement such a scheme, they'd very quickly realize their error and put an end to it. This is why the bank took down this system.


[Megan is holding a banknote up in one hand, while she is taking a picture of it with her smartphone held in the other hand. A starburst near the phone indicates the sound this makes. She is standing with her back to Cueball, who faces away from her. He is holding a banknote down by his side in one hand, while he is looking at his smartphone which he holds up in the other hand. From Cueball's phone there is a starburst from which a line goes up above him to indicate what is on the screen.]
Megan's phone: Click
Cueball's phone: Deposit accepted!
[Caption below panel:]
After a lucrative six hours for us, our bank removed the new feature in their app that let you deposit cash by taking a picture of it.

comment.png add a comment! ⋅ comment.png add a topic (use sparingly)! ⋅ Icons-mini-action refresh blue.gif refresh comments!


Depositing cash through a smartphone app was one of the silliest and most useful features in GTA V. Unfortunately, depositing money would not duplicate it. Presumably the characters in the game are very honest and trustworthy, destroying any cash instantly after scanning it in. This honesty is to be expected from thieving killers such as these.

You can also withdraw cash via the app. How that works is beyond me.

--NeatNit (talk) 23:38, 20 July 2020 (UTC)

A frequent joke in "The Goon Show" on 1950s British radio was the offer of a printed photograph of usually a small sum of money, treated as the photograph actually having value itself. Sometimes it's a phonograph disc. And sometimes the money represented turns out to be a forgery. In a less silly context, the photograph might be considered as an I.O.U., as evidence that the money exists and will be paid... which is what a banknote is, really. But in practice someone influencing you with pictures of money might be dishonest. Bank advertising for instance.

Wikipedia's article on "The Goon Show running jokes" (!) doesn't mention money photographs, although there is a reference to handing out pictures of Queen Victoria, especially in historical stories. Pictures of Queen Victoria may be on older money, but these ones don't seem to be.

Robert Carnegie [email protected] 08:18, 21 July 2020 (UTC)

Search for "photo"(graph) in http://www.thegoonshow.net/scripts_show.asp?title=s06e07_foiled_by_president_fred for the instant(s) that came straight to my mind, being recently broadcast. (I assume you're familiar with LSD?) 09:38, 21 July 2020 (UTC)

"Other nations ... have started introducing plastic banknotes" Lol. Australia had *finished* introducing plastic bank notes 30 years ago. [1] Boatster (talk) 01:43, 21 July 2020 (UTC)

Hmm. How much money would that be? Say each photo is 4MB and your upload speed is 25 or so Mb/s. Each upload would take about 1.3 secs. We'll round up to 1.5. To keep it simple, we'll say that they have a stack of bills, and are able to scan each new bill within those 1.5 seconds. Now, if the bank allows you to upload $100 bills, without any rate limiting, you'd be able to make $400/min (the same as the what if article, weird). Which means that in six hours, they could make $144,000 dollars! Of course, this is mostly guesswork, but it should be somewhere in the ballpark. Could be a little more: Smaller photos, better network. Or a lot less: Most people don't have $144,000 in cash ready at a moment's notice, and scanning could take more than 1.5 secs. Of course, if this was a feature that was announced, and they had time to prepare.... 04:11, 21 July 2020 (UTC)

$100*(60/1.5)sec = $4000 per min, or $1.44 million in 6 hours. You forgot that there are 2 phones, so double that. Also, you wouldn't need ALL the money, you (or an assistant) can take the money already scanned to another bank and swap it for new cash, repeat. 17:57, 22 July 2020 (UTC)

The feature of depositing check is this new or old... Is it something from before or after the Corona outbreak? It is a smart feature to avoid visits to banks during the pandemic - also the money thing, which of course is not realistic irl. --Kynde (talk) 09:19, 21 July 2020 (UTC)

depositing checks by smartphone is old, going back to 2018 if not earlier, and the depositing of currency could be realistic if bills used blockchain ledger entries instead of easily guessed serial numbers and everyone verified every currency transaction against the blockchain every time (this would end counterfeiting as a side effect). 09:53, 21 July 2020 (UTC)
Yes but that entirely defeats the purpose of cash, if you have to verify every transaction against a database. Also blockchain is entirely unnecessary. Probably not Douglas Hofstadter (talk) 06:11, 22 July 2020 (UTC)
The Chase app started allowing deposits ten years ago. See this article from ten years ago today: https://phys.org/news/2010-07-banking-deposit-smart-phone-photo.html Orion205 (talk) 03:44, 22 July 2020 (UTC)

Is it by the way illegal to even take a picture of banknote? I know printing one out is... Even if only one side and not very good quality. --Kynde (talk) 09:27, 21 July 2020 (UTC)

if taking pictures of banknotes is illegal then bank security cameras (and security cameras in many retail establishments and casinos) are routinely breaking the law. Also, aren’t change machines taking a picture as part of their anti-counterfeiting circuits? 09:58, 21 July 2020 (UTC)
Even printing banknote is legal if you follow some rules. I read that you need to make it bigger than 150% or smaller than 75% of real size, although details may vary depending on country. Of course, doesn't change the fact that your graphics program might refuse to work with that image and your printer may refuse to print it. -- Hkmaly (talk) 23:39, 21 July 2020 (UTC)
Not to mention that the act of depositing a check over a smartphone has been a thing for several years, so all the banks that offer this feature would be breaking the law as well. 23:12, 1 August 2020 (UTC)

I know it's acceptable in the 'colonial' idiom, but seeing "cheques" spelt as "checks" always confuses me for a micromoment. As well as imagining a test/verification being somehow a bartered service, I'm only just getting past it also being a bill-of-fare (in the UK we may pay a bill with a cheque, over there you can pay a check with a bill). But carry on carrying on! I'll get my coat. (If I can find the coat-check.) 10:01, 21 July 2020 (UTC)

Yes, we need to spell it as "chex" 17:46, 22 July 2020 (UTC)

Why is cryptocurrency in there, it seems tangential at best? Djbrasier (talk) 19:01, 21 July 2020 (UTC)

The more paranoid (or stand-offish for their own good reasons) Crypto users might not even connect bitwallets electronically but pass a transaction-code by other means (retyped from hardcopy, or rescan an on-screen generated QR, depending on requirements) and then rely upon the decentralised 'audit book' checking and authorising that transaction with minimal[citation needed] risk of subsequent tracing-and-linking-together by The Man/whoever. I think it's both far too paranoid and not paranoid enough, in equal measure, if you're trying to keep your associations off-grid, but it seems there are those who seem to like doing it that way. 20:35, 21 July 2020 (UTC)
cryptocurrency seems relevant, as the subject is about transmitting currency electronically and 'crypto' is about the closest thing you can get to real electronic cash 15:21, 23 July 2020 (UTC) Sam

The explanation seems excessive, given how obvious the joke is. Gvanrossum (talk) 04:58, 22 July 2020 (UTC)

Curse my memory over ~10-15years! I vaguely remember a traveler focused bank that accepted cash deposits. They'd add the amount to your account, you could spend it and they'd cover the costs, and if you didn't have the bills submitted to one of their locations across the globe within a certain amount of time they'd rip you a new one in fees. The photos had to be perfect, and even then they were up for review and could be rejected by a human who didn't like the background it was sitting on. I remember my parents only ever used it once and needed my help understanding it so it was just right. 18:50, 22 July 2020 (UTC)

This reminds me of that time Domino's allowed you to earn points to a free pizza by taking pictures of pizza. 22:34, 22 July 2020 (UTC)

When you got your free Pepperoni from that, did they put the slices on in the EURion pattern? ;) 23:03, 22 July 2020 (UTC)
I didn't actually do that. I'd rather eat somewhere else. 19:06, 25 July 2020 (UTC)

I wonder if Randall is subtly responding to the current coin shortage in the US, and the following wave of conspiracy theorists call it as a sign of an oncoming "cashless society" 15:21, 23 July 2020 (UTC) Sam

I hadn't heard about that, what states or news agencies are talking about that? 18:02, 24 July 2020 (UTC)