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Facial Recognition Failed in Boston Bombing

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Re: Facial Recognition Failed in Boston Bombing

#11

Post by UnoriginalGuy »

bsenftner wrote: post #3

My big questions is why were the suspects faces in the database? Why would a 19 year old, never done anything face be in the facial recognition database?

Everyone who enters the US is photographed and fingerprinted (e.g. tourists, visitors, etc).

Everyone who applies for a US visa is additionally photographed and fingerprinted.

Everyone who applies for naturalisation is additionally photographed and fingerprinted.

The suspects did all three of these things. The US government has almost every foreigner legally on American soil in a database.

Plus then you have the DNV on top of that and or passport office.

Re: Facial Recognition Failed in Boston Bombing

#12

Post by jhonovich »

I am the author of the referenced article. The problem is matching surveillance camera images (like from Lord & Taylor's) is impossible because of the steep down tilt angle of the cameras plus their low resolution. Smartphone images could be a little better as the angle is more head on and the resolution is higher. However, even those images tended to be in a wide field of view which means low pixel density, hurting matching performance. Last, but not least, the caps and sunglasses hurt recognition as well.

Re: Facial Recognition Failed in Boston Bombing

#13

Post by marknutter »

How hard would it be to throw off facial recognition by simply wearing very high quality makeup and prosthetics to alter your facial appearance (ala hollywood movies)? If I were the boston bombers, I would have first learned how to make myself look completely different. It's unbelievable to me that these guys didn't realize they'd be captured on tons of cameras that day.

Re: Facial Recognition Failed in Boston Bombing

#14

Post by sy_r0y »

aashaykumar92 wrote: post #2

When the FBI released the photos of the two suspects, I kept wondering, "Why do they need the publics help when I'm sure there is facial recognition software to help match the suspects' faces?" Well I guess this article somewhat answers this, but I am still in disbelief that our government does not have better software. For how long it took to discover their names, the two suspects had TOO much time to escape. They h…

I get what you mean when you say these guys had way too much time to make some kind of an escape and I agree then that there is an absolute need for a much better software. Having said that, I do not think it would be wise for government to build and use an "image crawler" to search and store images of citizens...it would provoke widespread criticism concerning privacy of millions of citizens. On top of that in this particular instance, the police commissioner points out that "both Tsarnaevs’ images exist in official databases"..the software failed to make a match.

Re: Facial Recognition Failed in Boston Bombing

#15

Post by nwh »

marknutter wrote: post #13

How hard would it be to throw off facial recognition by simply wearing very high quality makeup and prosthetics to alter your facial appearance (ala hollywood movies)? If I were the boston bombers, I would have first learned how to make myself look completely different. It's unbelievable to me that these guys didn't realize they'd be captured on tons of cameras that day.

If you wore Mission Impossible style masks, there's no reason why the facial recognition would be able to pick you up from underneath. You might alert the suspicion of people around you more though, as they don't ever seem to be perfect.

Re: Facial Recognition Failed in Boston Bombing

#16

Post by jere »

I watched this lecture recently http://youtu.be/-IUe3ce_29I which talked about how hard it is to do image recognition at low resolution. One solution is a "fovea" system that scans an area for interesting items and zooms in on them with a high resolution camera automatically to get better recognition.

I wonder if this would help in similar instances. A system that uses facial detection to isolate faces and then zoom in on them very quickly seems feasible. I'm assuming it would be overwhelmed in a scenario like a marathon of course, but perhaps it would help in other situations.

Re: Facial Recognition Failed in Boston Bombing

#17

Post by nwh »

ics wrote: post #10
bsenftner wrote: post #3

My big questions is why were the suspects faces in the database? Why would a 19 year old, never done anything face be in the facial recognition database?

I'm going to venture to guess that either a) the officer was talking out of his ass to make a quick point or b) someone, somewhere massively scraped every social network they could think of for anyone with ties to the area or the event. That being said, I don't really like the sound of it either, regardless of how true it is. --pre-submit thought: perhaps it was the older brother? Our background is rather limited but…

> massively scraped every social network

Funnily enough, if you download your information using Facebook's tools, you get a copy of your facial recognition data too. Presumably US law enforcement has access to that for their own uses.

Re: Facial Recognition Failed in Boston Bombing

#18

Post by eksith »

Bottom line is that it's nearly impossible to exactly match facial features to anyone beyond a set distance when there's too much ambiguity between distances and rubbish quality CCTV video.

Matching gait may be a more effective means of identification at a distance (and, in this and many other cases, at odd angles).

http://www.am.sanken.osaka-u.ac.jp/~sagawa/pdf/accv06.pdf (PDF)

Re: Facial Recognition Failed in Boston Bombing

#19

Post by xfs »

jhonovich wrote: post #12

I am the author of the referenced article. The problem is matching surveillance camera images (like from Lord & Taylor's) is impossible because of the steep down tilt angle of the cameras plus their low resolution. Smartphone images could be a little better as the angle is more head on and the resolution is higher. However, even those images tended to be in a wide field of view which means low pixel density, hurting…

Matching surveillance camera images is always possible no matter how bad the image quality is. The only matter is how many false positives show up.

Facial recognition algorithms always give their best matching candidates, with thresholds to skip those not quite matching ones. Your article makes it sound like no such results were produced at all, which is unlikely how recognition is supposed to work.

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