1. A method of refocusing a light field image in response to user input, the method comprising: receiving a light field image comprising light field data; digitally refocusing the light field image to generate a plurality of refocused images, each having a focus depth; storing the generated plurality of refocused images in a storage device; for each of a plurality of two-dimensional positions in the light field image: determining which of the plurality of refocused images is in focus at the two-dimensional position; and storing, in a look-up table, an index entry associating the two-dimensional position with the identified refocused image; displaying one of the refocused images, the displayed image having a first focus depth; receiving user input to select a two-dimensional position within the displayed image; and in response to the received input: retrieving, from the look-up table, an index entry identifying a stored refocused image corresponding to the selected two-dimensional position, the stored refocused image having a second focus depth different from the first focus depth; retrieving the identified refocused image from the storage device; and displaying the retrieved refocused image having the second focus depth.