Systems and methods for encoding light field image files
Systems and methods configured to store images synthesized from light field image data and metadata describing the images in electronic files and render images using the stored image and the metadata in accordance with embodiments of the invention are disclosed. One embodiment includes a processor and memory containing an encoding application and light field image data, where the light field image data comprises a plurality of low resolution images of a scene captured from different viewpoints. In addition, the encoding application configures the processor to: synthesize a higher resolution image of the scene from a reference viewpoint using the low resolution images, where synthesizing the higher resolution image involves creating a depth map that specifies depths from the reference viewpoint for pixels in the higher resolution image; encode the higher resolution image; and create a light field image file including the encoded image and metadata including the depth map.
1. A system for encoding light field image data as a light field image file, comprising:
a processor; and
memory containing an encoding application and light field image data, where the light field image data comprises a plurality of low resolution images of a scene captured from different viewpoints;
wherein the encoding application configures the processor to:
synthesize a higher resolution image of the scene from a reference viewpoint using the low resolution images, where synthesizing the higher resolution image involves creating a depth map that specifies depths from the reference viewpoint for pixels in the higher resolution image and the higher resolution image has a higher resolution than the low resolution images;
encode the higher resolution image; and
create a light field image file including the encoded image and metadata describing the encoded image, where the metadata includes the depth map.
2. The system of claim 1 , wherein the encoding application configures the processor to encode the depth map and the depth map included in the metadata describing the encoded image is the encoded depth map.
3. The system of claim 1 , wherein:
synthesizing the higher resolution image involves identifying pixels in the plurality of low resolution images of the scene that are occluded in the reference viewpoint; and
the metadata describing the encoded image in the light field image file includes descriptions of the occluded pixels.
4. The system of claim 3 , wherein the descriptions of the occluded pixels include colors, locations, and depths of the occluded pixels.
5. The system of claim 3 , wherein:
synthesizing the higher resolution image involves creating a confidence map for the depth map, where the confidence map indicates the reliability of the depth value for a pixel in the depth map; and
the metadata describing the encoded image in the light field image file includes the confidence map.
6. The system of claim 5 , wherein the encoding application configures the processor to encode the confidence map.
7. The system of claim 3 , wherein:
the encoding application configures the processor to generate an edge map that indicates pixels in the synthesized image that lie on a discontinuity; and
the metadata describing the encoded image in the light field image file includes the edge map.
8. The system of claim 7 , wherein the edge map identifies whether a pixel lies on an intensity discontinuity.
9. The system of claim 7 , wherein the edge map identifies whether a pixel lies on an intensity and depth discontinuity.
10. The system of claim 7 , wherein the encoding application configures the processor to encode the edge map.
11. The system of claim 3 , wherein:
the encoding application configures the processor to generate a missing pixel map that indicates pixels in the synthesized image that do not correspond to a pixel from the plurality of low resolution images of the scene and that are generated by interpolating pixel values from adjacent pixels in the synthesized image; and
the metadata describing the encoded image in the light field image file includes the missing pixels map.
12. The system of claim 11 , wherein the encoding application configures the processor to encode the missing pixels map.
13. The system of claim 1 , wherein the metadata also includes a focal plane.
14. The system of claim 1 , wherein the light field image file conforms to the JPEG File Interchange Format (JFIF) standard.
15. The system of claim 14 , wherein the high resolution image is encoded in accordance with the JPEG standard.
16. The system of claim 15 , wherein the metadata is located within an application marker segment within the light field image file.
17. The system of claim 16 , wherein the application marker segment is identified using an APP9 marker.
18. The system of claim 16 , wherein the encoding application configures the processor to encode the depth map in accordance with the JPEG standard using lossless compression and the encoded depth map is stored within the application marker segment containing the metadata.
19. The system of claim 18 , wherein:
synthesizing the higher resolution images involves identifying pixels from the plurality of low resolution images of the scene that are occluded in the reference viewpoint; and
descriptions of the occluded pixels are stored within the application marker segment containing the metadata.
20. The system of claim 19 , wherein the descriptions of the occluded pixels include colors, locations, and depths of the occluded pixels.
21. The system of claim 16 , wherein:
synthesizing the higher resolution image involves creating a confidence map for the depth map, where the confidence map indicates the reliability of the depth value for a pixel in the depth map; and
the confidence map is stored within the application marker segment containing the metadata.
22. The system of claim 21 , wherein the encoding application configures the processor to encode the confidence map in accordance with the JPEG standard using lossless compression.
23. The system of claim 16 , wherein:
the encoding application configures the processor to generate an edge map that indicates pixels in the synthesized image that lie on a discontinuity; and
the edge map is stored within the Application marker segment containing the metadata.
24. The system of claim 23 , wherein the edge map identifies whether a pixel lies on an intensity discontinuity.
25. The system of claim 23 , wherein the edge map identifies whether a pixel lies on an intensity and depth discontinuity.
26. The system of claim 23 , wherein the encoding application configures the processor to encode the edge map in accordance with the JPEG standard using lossless compression.
27. The system of claim 16 , wherein:
the encoding application configures the processor to generate a missing pixel map that indicates pixels in the synthesized image that do not correspond to a pixel from the plurality of low resolution images of the scene and that are generated by interpolating pixel values from adjacent pixels in the synthesized image; and
the missing pixel map is stored within the Application marker segment containing the metadata.
28. The system of claim 27 , wherein the encoding application configures the processor to encode the missing pixels map in accordance with the JPEG standard using lossless compression.
29. A method for encoding light field image data as a light field image file, comprising:
synthesize a higher resolution image of a scene from a reference viewpoint and a depth map that describes depths of pixels in the synthesized image using an encoding device and light field image data, where the light field image data comprises a plurality of low resolution images of a scene captured from different viewpoints and synthesizing the higher resolution image includes creating a depth map that specifies depths from the reference viewpoint for pixels in the higher resolution image;
encoding the higher resolution image using the encoding device, where the higher resolution image has a higher resolution than the low resolution images; and
creating a light field image file including the encoded image and metadata describing the encoded image using the encoding device, where the metadata includes the depth map.
30. A non-transitory machine readable medium containing processor instructions, where execution of the instructions by a processor causes the processor to perform a process comprising:
synthesizing a higher resolution image of a scene from a reference viewpoint using light field image data, where the light field image data comprises a plurality of low resolution images of a scene captured from different viewpoints and synthesizing the higher resolution image includes creating a depth map that specifies depths from the reference viewpoint for pixels in the higher resolution image;
encoding the higher resolution image, where the higher resolution image has a higher resolution than the low resolution images; and
creating a light field image file including the encoded image and metadata describing the encoded image, where the metadata includes the depth map.