Wikipedia:Reference desk/Archives/Computing/2014 March 25

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March 25

Does makeup confuse modern facial recognition systems?

Can they automatically tell sunken eyes from eyeshadowed eyes, for instance? Or do our face wrinkles have "fingerprints" that foundation might obscure? Any other such stuff? InedibleHulk (talk) 03:26, 25 March 2014 (UTC)

I believe that most systems build a model of the face and use distances between features. There is speculation in a recent new scientist that avant-guarde high-contrast makeup could fool facial recognition by making it hard to detect the measurement points, though normal makeup probably wouldn't help. -- Q Chris (talk) 08:48, 25 March 2014 (UTC)

There are a variety of different approaches out there - some use video footage rather than a single still image. The varying viewpoint allows them to extract three-dimensional information. Others use two cameras to capture a stereo view for the same reason - or employ "structured light" (kinda like the "Kinect" gadget) to achieve the same basic result. Knowing the three-dimensional shape of the face makes it much harder to disguise with makeup. So I suspect that these clever makup tricks could confuse simpler systems, but if large numbers of people started employing these tricks, the technology could easily evolve to fix that. Of course wearing big sunglasses and a false moustache works pretty well too! You might be interested in our Eigenface and Active shape model articles that cover some of the techniques. SteveBaker (talk) 14:15, 25 March 2014 (UTC)

Thanks, I'd have never thought to find those articles. I'm mainly thinking of 2D "#nomakeupselfies". They seem otherwise pointless. Of course, planking was also rather pointless, and generally harmless. Maybe I'm paranoid. InedibleHulk (talk) 16:50, 25 March 2014 (UTC)

You also might be able to confuse them by being dark skinned. Matt Deres (talk) 11:13, 27 March 2014 (UTC)

Cracked told me about the HP ones doing that. May not prove racism, but it does suggest they don't hire black testers. InedibleHulk (talk) 03:04, 28 March 2014 (UTC)

How are commands entered into a Game Boy Advance running UNIX?

How are commands entered at the shell prompt of a Game Boy Advance running UNIX as shown here? 20.137.2.50 (talk) 17:20, 25 March 2014 (UTC)

From the page you linked: "gbaunix does not have an input mechanism currently. You can only execute a canned sequence of UNIX shell commands. The sequence must be specified at compile-time as an array of strings in gba/gba_kbd.h in the source. While UNIX is running, pressing the START button feeds the next command line into the TTY's input buffer." - Cucumber Mike (talk) 17:25, 25 March 2014 (UTC)

Thanks. You don't happen to see there how one actually gets one's gbaunix physically onto a real cartridge, do you? 20.137.2.50 (talk) 18:01, 25 March 2014 (UTC)

Nevermind, I assume it would be using a Flash Cartridge. 20.137.2.50 (talk) 18:14, 25 March 2014 (UTC)

No MX or A records for nauta.cu

If I were to receive the following message on an email returned to me, could the casue be the monthly data limit was reached? Is some other cause likely?

---

Sorry, we were unable to deliver your message to the following address.

<name redacted@nauta.cu>: No MX or A records for nauta.cu

---

Thanks. μηδείς (talk) 19:26, 25 March 2014 (UTC)

If you're talking about the data limit for the entire nauta.cu domain, then there's a remote chance if the mail server provider intentionally removes the MX or A records presuming they have that control when the quota runs out to reduce the amount of traffic they receive. Since they seem to also control the nameservers, they probably do in this case. I've never actually heard of anyone doing this, but I'm not that familiar with mail server hosting practices, even less in Cuba.

There's no chance this could happen for simply one email account in the domain under any resonable circumstances regardless of whether it exceeded the quote limit, your email tripped some censorship filter or whatever. More specifically, some mailserver involved (I don't know from what you quoted what mailserver sent this although I would expect it to be the mail server you used or another controlled by the same company) would need to be seriously (most likely intentionally) misconfigured to do this as they are basically lying about the cause of the failure and in a way that makes no sense.

The more likely explaination is some temporary misconfiguration or mistake. When I did a nslookup just now [1], I did find multiple MX records (no A but that may be normal, it sounds like the domain is only used for email). So I would try the email right now. If it still doesn't work give it another 3 days or so (you can probably try every day or less without risk) for the intermediate mail server DNS caching to catch up with the DNS update.

If it still doesn't work after 3 days and there is still a MX record then there may be a problem with some mail server involved, so try using a different service. (The other possibility is the name server keeps adding and removing the MX record and you mail server gets it at the wrong time and you get it at the right time. I guess it's also possible the name server is refusing to provide an MX record to whichever name server is requesting it for your mail server.)

Nil Einne (talk) 21:18, 25 March 2014 (UTC)

Thanks. What has been going on from my end is a user at that domain has been requesting files of 1-2 MB on average, but requested one last night that I did not realize was 27MB. According to press reports, these files cost about $1 per MB, while the average monthly income is $20. I fear what I have sent may cost several month's wages. I am wondering if I can compensate from my ownend, and hoping there's noting worse I have done than what I imagine. μηδείς (talk) 21:59, 25 March 2014 (UTC)

I have been able to send two messages but received no response, and gotten two inquiries aking if there's a problem, but no response to me answer to those inquiries. μηδείς (talk) 13:44, 26 March 2014 (UTC)

So far this seems to be some sort of problem with Yahoo. For two days prior Yahoo wouldn't upload attachments even bore you had the email addressed or tried sending them. Using a new gmail account I have been able to get through to the nauta.cu address. I just sent another text file through yahoo which hasn't come back yet. (I'd use gmail exclusively, but the format seems harder to read.) I was wondering if there was any reporting on this in the media. I remember when it became possible to make direct phone calls a decade ago. They cost an enormous amount of money (like $5/min) and where of terrible quality, with the US carriers pocketing a good amount of the money. Any links to news on the relevant issues would be helpful. Thanks. μηδείς (talk) 19:07, 26 March 2014 (UTC)

To follow up on this, in case anyone else is in the same predicament, I have not had problems with gmail going through for the last two days, although at first there was a "box is full" message. Yahoo will not go through at all at this point, whether it's a short text email or has an attachment, I still get the original "No MX or A Records" error message. μηδείς (talk) 04:20, 29 March 2014 (UTC)