Feeds

Google boffins beat own Captchas

The StreetView numbers game

Providing a secure and efficient Helpdesk

A group of Google scientists working on extracting numbers from StreetView images has discovered that their technology can also match humans at solving captchas.

The aim, according to their research paper (at Arxiv, here), was to automatically extract accurate street number data from StreetView images so as to improve Google Maps location information.

Prior work, the researchers write, had worked on extracting individual numbers from an image, identifying each number, and then reassembling the whole street number. This, however, is inefficient, so the group let by Ian Goodfellow focussed on taking an entire image and identifying all the numbers in it.

Testing their model on Google's StreetView House Numbers dataset (which contains 200,000 numbers), the researchers found they were able to match human accuracy of 98 per cent with “95.64 per cent coverage”.

To achieve that accuracy, the researchers spent six days training Google's DistBelief neural network modelling framework. That training was then applied to all the house numbers Google holds – well into the tens of millions. The less constrained dataset reduced coverage down to 89 per cent while holding accuracy at the 98 per cent “equal to a human” threshold.

Google's Street View number recognition

Getting numbers out of images is easy, says Google

The same model was then tested against Google's reCAPTCHA puzzle, achieving 99.8 per cent accuracy. The researchers write that while this doesn't render Captchas useless, “the utility of distorted text as a reverse turing test by itself is significantly diminished”.

As Google's Vinay Shet writes in this blog post, “the act of typing in the answer to a distorted image should not be the only factor when it comes to determining a human versus a machine”, and Google itself is reducing its “dependence on text distortions as the main differentiator between human and machine,” using Captchas instead to “perform advanced risk analysis”. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
SMASH the Bash bug! Apple and Red Hat scramble for patch batches
'Applying multiple security updates is extremely difficult'
Shellshock: 'Larger scale attack' on its way, warn securo-bods
Not just web servers under threat - though TENS of THOUSANDS have been hit
Apple's new iPhone 6 vulnerable to last year's TouchID fingerprint hack
But unsophisticated thieves need not attempt this trick
Hackers thrash Bash Shellshock bug: World races to cover hole
Update your gear now to avoid early attacks hitting the web
Oracle SHELLSHOCKER - data titan lists unpatchables
Database kingpin lists 32 products that can't be patched (yet) as GNU fixes second vuln
Who.is does the Harlem Shake
Blame it on LOLing XSS terroristas
Researchers tell black hats: 'YOU'RE SOOO PREDICTABLE'
Want to register that domain? We're way ahead of you.
Stunned by Shellshock Bash bug? Patch all you can – or be punished
UK data watchdog rolls up its sleeves, polishes truncheon
prev story

Whitepapers

A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.