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by frankiejr 3886 days ago
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.
2 comments
amluto 3886 days ago
Huh, guess I'm out of date here.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.

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dwaxe 3885 days ago
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

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catbird 3885 days ago
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...

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aaronsnoswell 3885 days ago
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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