With unlimited data plans becoming increasingly expensive, or subscribers being forced to ditch their unlimited data due to overuse, anything that can reduce the amount of data we download is welcome. This is especially true for media including images or video, and Google just delivered a major gain when it comes to viewing images online.
The clever scientists at Google Research have come up with a new technique for keeping image size to an absolute minimum without sacrificing quality. So good is this new technique that it promises to reduce the size of an image on disk by as much as 75 percent.
The new technique is called RAISR, which stands for “Rapid and Accurate Image Super-Resolution.” Typically, reducing the size of an image means lowering its quality or resolution. RAISR works by taking a low-resolution image and upsampling it, which basically means enhancing the detail using filtering. Anyone who’s ever tried to do this manually knows that the end result looks a little blurred. RAISR avoids that thanks to machine learning.
The eyes image above is a great example, as is the horse head below. In both cases, the lower resolution is the data being worked with, and the higher resolution version being what RAISR produces after filtering. The quality gain is clear to see:
By showing RAISR a low quality image, it can intelligently upscale it to look like a high quality equivalent. Just as importantly, it does this on your device after the data-saving low resolution image has been downloaded, with the conversion happening in real-time even on mobile devices.
RAISR has been trained using low and high quality versions of images. Machine learning allows the system to figure out the best filters to recreate the high quality image using only the low quality version. What you end up with after lots of training is a system that can do the same high quality upsampling on most images without needing the high quality version for reference.
Anyone visiting Google+ since November has probably already seen images that have been tweaked by RAISR. It’s currently handling over a billion images a week and saving an enormous amount of bandwidth for end users. Over the coming weeks, Google will quietly start using it “more broadly” across its services.