Feeds

Google boffins beat own Captchas

The StreetView numbers game

Intelligent flash storage arrays

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”. ®

Top 5 reasons to deploy VMware with Tegile

Whitepapers

Choosing cloud Backup services
Demystify how you can address your data protection needs in your small- to medium-sized business and select the best online backup service to meet your needs.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.