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Comment by frankiejr | Hacker News Reader

Lytro switched away from Flash to a JPEG/JavaScript player in 2013, then to a WebGL player in late 2014. There were some open source player controls floating around last year but I can't recall the name. There were also some open source tools to extract the JPEG stack from the .LFP file as well, which you could use to build a player of your own. I worked at Lytro from 2012-2015 and we'd see occasional updates from those tools.

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Huh, guess I'm out of date here.

Is it really a JPEG stack? I had assumed there was more magic (i.e. math and clever compression) than that. Or is a JPEG stack with extra fanciness?

I'd love to read up on how this stuff actually works. I know how to calculate the theoretical information capacity in a light field (hint: very very dense) but basically nothing about how people manage to munge it into something compact and useful.

At its core, the viewer works by just averaging the JPEG stack at varying offsets as described in this student project: https://inst.eecs.berkeley.edu/~cs194-26/fa14/upload/files/p...

I haven't looked into how they make everything efficient, but the source code for their flash viewer is here http://lightfield.stanford.edu/aperture.html

Well, the raw picture (light field) from the camera looks like something from an insect's eye - a hexagonal grid of tiny pictures saved into one giant jpeg [1]. The Lytro software processes that data into a stack of jpegs of reconstructed views at varying focal lengths when you first import the image.

[1] see for example http://lightfield-forum.com/2012/07/lytro-hack-how-to-extrac...

The Light Field Toolbox by Donald Dansereau allows you to view and modify Lytro Light fields and is open source, I've used it before.

http://www.mathworks.com/matlabcentral/fileexchange/49683-li...

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