Is there reference code for implementing light field photography?

Question

Many of us here at photo SE have read about light field photography and related cameras from Lytro and Raytrix.

A few of the advantages it allows are post-capture software focus, scene perspective changing and manipulation, and 3D video.

Are there any reference software implementations or available demo code of lightfield imaging for the above features and the related algorithms? (I read that FFT/IFFT is the tool used in obtaining software-focussed images, but I do not understand the full details of this.)

I've heard rumors that Nvidia Cuda has some thing for it, but I need more details if anyone has them.

Answer

I'm not sure about reference code; this is relatively new, and mostly what I can find are papers, not implementations with open code. A key paper is Fourier Slice Photography, by Ren Ng at Stanford University — now, not surprisingly, at Lytro. There's an abstract of the paper here, with a few nice pictures.

This doesn't give you something that you can take and just drop into place, but it gives you some technical, mathy details of how to go from the output of a plenoptic camera to a usable result. Of course, that's not all: for more, take a look at Ng's 200+-page PhD thesis on the topic.

You will probably also find the materials for MIT's MAS.531 / MAS.131 Computational Camera and Photography helpful. Thanks to the OpenCourseWare initiative, you can download and go through all the course materials yourself (including audio from the lectures).

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