October 12, 2006

Hardware and software scheme avoids JPEG compression, could allow 10 times better resolution for cameras

When a multi-megapixel digital camera snaps a shot, most of the information doesn't even make it into the final photo file. About 90 percent of information is lost during the compression process that creates a JPEG file. hey've built and tested the hardware and software for a camera that collects just enough information to recreate a picture, while avoiding the traditional compression process. Incorporating these algorithms into commercial cameras could allow a two-megapixel camera to snap 20-megapixel photos.

In a prototype, the researchers used an array of tiny mirrors--a technology developed by Texas Instruments that's already used in high-definition projection televisions. The micromirror array takes in a small amount of information, and directs it onto a single sensor. Then algorithms are used to reconstruct the image. Since the prototype has only one sensor, in effect it's a single-pixel camera. However, the algorithm recreates an image with 100 times the resolution of what would traditionally be captured in a single pixel.

Baraniuk and his team recognized that an emerging field of information theory, called "compressive sensing," offered an alternative approach to conventional image acquisition and compression.

The researcher's camera has a long way to go before it's in a commercialized form, though, notes Baraniuk. Right now, the setup spans an optical table in a lab, and the researchers' algorithms are slow compared with the compression in commercial cameras. The group is working to make its algorithms faster, and, Baraniuk adds, the hardware continues to improve as more micromirrors are being added to smaller arrays, and their flipping speed increases.

Baraniuk expects that the first application for the new camera could be in terahertz imaging systems--systems that use terahertz-frequency radiation to see through objects and detect small amounts of chemicals. Currently, it's expensive to build the large sensors needed for these systems, he says, so a single-sensor camera like the one the group developed would be ideal.

I would predict that within 6-10 years this will reach commercial cameras. Then digital cameras that are at 20 to 500 megapixels will get a ten times boost in resolution.

This relates to a computing prediction that I made at the beginning of this year
Gigapixel cameras common 2009-2015

Currently we are almost at expensive gigapixel cameras using backplane technology which has slow image capture

Related info:
111 megapixel CCD on a single chip This chip combined with the system that was just developed would provide gigapixel cameras.

Imaging with 50 times less power and other efficiency improvements