Ever taken a digital photograph and then found out you had missed the fine details that made the scene so impressive visually? Applying a Photoshop sharpen filter may make the photo appear sharper, but such filters are lossy – they actually reduce the amount of fine detail in the image. Until recently, there was very little you could do to improve the image after the shot. Researchers at the Weizmann Institute of Science have now developed a super-resolution process which pulls unseen details from the nooks and crannies of a single digital photograph. Their process can capture true detail which cannot be seen in the original image – the next “killer app”?
Super-resolution is a set of image processing techniques that extract a high-resolution image from multiple low-resolution images of the same subject. A high-resolution image retrieves image details not visible in any single low-resolution image, even in principle.
When you convert an optical image into a digital image, unavoidable errors occur through conversion of a continuously varying light intensity into a set of pixels each measuring (roughly) the average amount of light on the small area of each pixel. The digital image does an excellent job of reproducing images whose optical intensity varies slowly. However, if the image contains features that vary rapidly (edges, corners, zig-zags), these features will be altered by aliasing – for example by introduction of Moire fringes onto the image. Via Impressive new approach to super-resolution processing developed.