Single-pixel camera uses digital multimirror to compress image

[Martin]

this has clear diagrams and sample images:

http://www.dsp.ece.rice.edu/cscamera/

 

the camera uses a DMD (digital micromirror device) as explained here

http://www.aip.org/pnu/2006/split/797-2.html?source=rsspnu

 

here is wiki about DMD

http://en.wikipedia.org/wiki/Digital_micromirror_device

 

here is a rough paraphrase:

conventional digital cameras do a fourier transform numerically to compress a million numbers down to 10,000 (image is then stored as 10,000)

but first they have to store the million numbers.

 

this new concept of camera does the fourier transform data compression FIRST before storing anything, in a kind of analog way using a DMD

so it never has to store the million numbers, only the 10,000

 

===quote===

...The new approach aims to confront one of the basic dilemmas of digital imaging, namely the huge waste factor.

 

Consider that a megapixel camera will, when you take the picture, capture and momentarily store a million numbers (the light levels from the pixels). No camera can store that much information for hundreds of pictures, so an immediate data compression takes place right there inside the camera. A tiny microprocessor performs a Fourier transform; that is, it converts the digital image into a weighted sum of many sinusoid waves. Instead of a million numbers, the representation of the image can now been compressed into something like 10,000 numbers, corresponding to the most important coefficients from the mathematical transformation. These are the numbers actually retained for later processing into pictures.

 

The Rice camera saves space and energy by eliminating the first step. It gets rid of the million pixels. Instead, it goes right to a transformed version (about 10,000 numbers rather than a million) by viewing the scene prismatically with a single pixel....

===endquote===