MIT uses algorithm to banish window reflections in pics

The software can automatically remove reflections when photographing through windows

Researchers at MIT have developed an algorithm that can automatically separate window reflections from a digital image (left) and remove them (top right).

Researchers at MIT have developed an algorithm that can automatically separate window reflections from a digital image (left) and remove them (top right).

You've got the perfect shot of a cityscape from your hotel room -- if it weren't for those pesky reflections in the window.

Photographers are often stymied by their own reflection or that of their camera when shooting through glass, but researchers at MIT and Google Research have developed a method to remove them automatically.

The technique finds glass reflections in photos by using the fact that they're usually made up of two reflections, one slightly offset from the other.

The two reflections can be caused by double panes in windows or even a single, thick pane, resulting in a double or "ghosted" reflection. Since the second reflection is a set distance from the first, the researchers used an algorithm to distinguish the reflections from all the other data in the image.

The algorithm, using a technique developed by MIT's Daniel Zoran and Yair Weiss of Hebrew University of Jerusalem, separates images into 8-by-8-pixel squares. It uses statistics related to the pixels to first detect the separation between the two reflections and then remove the reflections.

The algorithm was trained using tens of thousands of images in databases, and the researchers say it can work in most situations.

Sample images distributed by MIT and in the researchers' paper on the topic showed a variety of results.

In one, the original image shows a fire-escape staircase shot through a window, with the photographer's reflection clearly visible. After processing with the algorithm, the reflection is nearly all gone from the photo, but faint traces of the person's face are visible in the wall by the fire escape.

With refinements, such image-processing software could be useful in smartphones and digital cameras. It could also help machines that use computer vision, such as robots and self-driving cars, make sense of environments where reflections are present.

"The work has potential in improving degraded pictures due to window reflection, like when window shopping," graduate student YiChang Shih from MIT's Computer Science and Artificial Intelligence Laboratory said via email.

Shih said he wants to make the algorithm's ability to detect reflections more robust, but he wouldn't say if or when the research could be commercialized.

The research is to be presented at the Computer Vision and Pattern Recognition conference in Boston in June.

Tim Hornyak covers Japan and emerging technologies for The IDG News Service. Follow Tim on Twitter at @robotopia.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

Tags Googleconsumer electronicsdigital camerasMassachusetts Institute of TechnologyGoogle research

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Tim Hornyak

IDG News Service
Show Comments

Cool Tech

Toys for Boys

Family Friendly

Stocking Stuffer

SmartLens - Clip on Phone Camera Lens Set of 3

Learn more >

Logitech Ultimate Ears Wonderboom Bluetooth Speaker

Learn more >

Christmas Gift Guide

Click for more ›

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Maryellen Rose George

Brother PT-P750W

It’s useful for office tasks as well as pragmatic labelling of equipment and storage – just don’t get too excited and label everything in sight!

Cathy Giles

Brother MFC-L8900CDW

The Brother MFC-L8900CDW is an absolute stand out. I struggle to fault it.

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Andrew Teoh

Brother MFC-L9570CDW Multifunction Printer

Touch screen visibility and operation was great and easy to navigate. Each menu and sub-menu was in an understandable order and category

Featured Content

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?