Systems and methods for encoding image files containing depth maps stored as metadata

• US 9,864,921 B2
• Filed: 03/24/2015
• Issued: 01/09/2018
• Est. Priority Date: 09/28/2011
• Status: Active Grant

• Current Assignee: FotoNation Limited (Adeia Inc.)
• Original Assignee: Fotonation Cayman Limited
• Inventors: Venkataraman, Kartik, Nisenzon, Semyon, Lelescu, Dan
• Primary Examiner(s): Dang, Duy M
• Application Number:
  US14/667,503
• Publication Number:
  US 20150199794A1
• Time in Patent Office: 1,022 Days
• CPC Class Codes: G06T 15/08 Volume rendering
• CPC Class Codes: G06T 2207/10052 Images from lightfield camera
• CPC Class Codes: G06T 3/4007 based on interpolation, e.g. bilinear interpolation image demosaicing G06T3/4015; edge-driven or edge-based scaling G06T3/403
• CPC Class Codes: G06T 3/4053 based on super-resolution, i.e. the output image resolution being higher than the sensor resolution
• CPC Class Codes: G06T 7/50 Depth or shape recovery
• CPC Class Codes: G06T 7/596 from three or more stereo images
• CPC Class Codes: G06T 9/00 Image coding bandwidth or redundancy reduction for static pictures H04N1/41; coding or decoding of static colour picture signals H04N1/64; methods or arrangements for coding, decoding, compressing or decompressing digital video signals H04N19/00
• CPC Class Codes: G06T 9/20 Contour coding, e.g. using detection of edges
• CPC Class Codes: H04N 13/128 Adjusting depth or disparity
• CPC Class Codes: H04N 13/139 Format conversion, e.g. of frame-rate or size
• CPC Class Codes: H04N 13/161 Encoding, multiplexing or demultiplexing different image signal components for multi-view video sequence encoding H04N19/597
• CPC Class Codes: H04N 13/178 Metadata, e.g. disparity information
• CPC Class Codes: H04N 13/243 using three or more 2D image sensors
• CPC Class Codes: H04N 13/271 wherein the generated image signals comprise depth maps or disparity maps
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/593 involving spatial prediction techniques
• CPC Class Codes: H04N 19/597 specially adapted for multi-view video sequence encoding
• CPC Class Codes: H04N 19/625 using discrete cosine transform [DCT]
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/85 using pre-processing or post-processing specially adapted for video compression
• CPC Class Codes: H04N 2013/0081 : Depth or disparity estimation from stereoscopic image signals

Abstract

Systems and methods for storing images synthesized from light field image data and metadata describing the images in electronic files 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, the low resolution images, and metadata including the depth map.

Claims

1. An image processing system, comprising:

a processor; and

memory containing an encoding application;

wherein the encoding application directs the processor to;

obtain image data, where the image data comprises a plurality of images of a scene captured from different viewpoints;

create a depth map that specifies depths for pixels in a reference image using at least a portion of the image data; and

store an image file including the reference image, and the depth map stored as metadata within the image file in the memory.

2. The system of claim 1, wherein the encoding application directs the processor to encode the depth map.

3. The system of claim 1, wherein the encoding application directs the processor to:

identify pixels in the plurality of images of the scene that are occluded in the reference image; and

the metadata 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 1, wherein the encoding application directs the processor to:

create 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 further includes the confidence map.

6. The system of claim 5, wherein the encoding application directs the processor to encode the confidence map.

7. The system of claim 1, wherein:

the encoding application directs the processor to generate an edge map that indicates pixels in the reference image that lie on a discontinuity; and

the metadata further 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 directs the processor to encode the edge map.

11. The system of claim 1, wherein:

the encoding application directs the processor to generate a missing pixel map that indicates pixels in the reference image that do not correspond to a pixel from the plurality of images of the scene; and

the metadata further includes the missing pixels map.

12. The system of claim 11, wherein the encoding application directs the processor to encode the missing pixels map.

13. The system of claim 1, wherein at least one of the plurality of images is captured from a viewpoint that is separate and distinct from a viewpoint of the reference image.

14. The system of claim 1, wherein the image file conforms to the JPEG File Interchange Format (JFIF) standard.

15. The system of claim 14, wherein the reference 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 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 directs 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 image processing system of claim 1, wherein the encoding application further directs the processor to synthesize the reference image of the scene from the reference viewpoint using the image data and synthesizing the image includes creating the depth map.

20. The image processing system of claim 19, wherein the encoding application further directs the processor to store at least one of the plurality of images of a scene captured from different viewpoints as metadata in the image file.

21. The image processing system of claim 19, wherein the encoding application further directs the processor to store the plurality of images of a scene captured from different viewpoints in the image file.

22. The image processing system of claim 19, wherein the plurality of images of a scene captured from different viewpoints comprises a stereo pair of images captured by an array camera.

23. The image processing system of claim 19, wherein synthesizing the image applies an effect selected from the group consisting of blur, focus, and zoom.

24. The image processing system of claim 19, wherein the encoding application further directs the processor to synthesize the reference image by applying a blur to refocus a previous version of the reference image.

25. The image processing system of claim 19, wherein the encoding application further directs the processor to synthesize the reference image by applying a depth based effect to a previous version of the reference image using the depth map.

26. The image processing system of claim 19, wherein in the encoding application further directs the processor to encode the reference image.

27. The image processing system of claim 26, wherein the image file is stored in the memory of the image processing system.

28. The image processing system of claim 27, wherein the image file is moved to a different location within the memory of the image processing system.

29. The image processing system of claim 27, wherein the encoding application further directs the processor to transfer the image file to a rendering device.

30. The image processing system of claim 29, wherein the rendering device is capable of rendering the reference image using the image file.

31. The image processing system of claim 29, wherein:

the encoding application further directs the processor to store the plurality of images of a scene captured from different viewpoints in the image file; and

the second rendering device comprises;

a second processor; and

and a second memory containing a rendering application;

wherein the rendering application directs the second processor to synthesize a new image of the scene from;

image data contained in the image file including the plurality of images of the scene captured from different viewpoints; and

the depth map.

32. The image processing system of claim 31, wherein the rendering application directs the second processor to apply an effect to the new synthesized image using the depth map in the image file.

33. A method for encoding image data as an image file, comprising:

synthesizing an 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 image data, where the image data comprises a plurality of images of a scene captured from different viewpoints and synthesizing the image includes creating a depth map that specifies depths from the reference viewpoint for pixels in the image;

encoding the the synthesized image using the encoding device; and

creating an image file including the encoded image, and metadata describing the encoded image using the encoding device, where the metadata includes the depth map.

34. The method of claim 33, further comprising encoding the depth map using the encoding device.

35. The method of claim 33, wherein the image file conforms to the JPEG File Interchange Format (JFIF) standard.

36. The method of claim 35, wherein the reference image is encoded in accordance with the JPEG standard.

37. The method of claim 33, wherein the metadata is located within an application marker segment within the image file.

38. The method of claim 37, wherein the application marker segment is identified using an APP9 marker.

39. The method of claim 33, wherein:

the depth map is encoded in accordance with the JPEG standard using lossless compression; and

the encoded depth map is stored within the application marker segment containing the metadata.

40. The method of claim 33, further comprising using the encoding device to store at least one of the plurality of images of a scene captured from different viewpoints as metadata in the image file.

41. The method of claim 33, further comprising using the encoding device to store the plurality of images of a scene captured from different viewpoints in the image file.

42. The method of claim 33, wherein the plurality of images of a scene captured from different viewpoints comprises a stereo pair of images captured by an array camera.

43. The method of claim 33, wherein synthesizing the synthesized image comprises applying an effect selected from the group consisting of blur, focus, and zoom.

44. The method of claim 33, wherein synthesizing the synthesized image further comprises applying a blur to refocus a previous version of the reference image.

45. The method of claim 33, wherein synthesizing the synthesize image comprises applying a depth based effect to a previous version of the reference image using the depth map.

46. The method of claim 33, further comprising transmitting the image file to a rendering device capable of rendering the reference image using the image file.

47. The method of claim 46, further comprising:

using the encoding device to store the plurality of images of a scene captured from different viewpoints in the image file; and

synthesize a new image of the scene using the rendering device based upon;

image data including the plurality of images of the scene in the image file captured from different viewpoints;

and the depth map.

48. The method of claim 47, further comprising applying an effect to the new synthesized image based upon the depth map in the image file using the rendering device.

49. The method of claim 48, wherein:

the encoding device comprises a processor and memory containing an encoding application; and

the rendering device comprises a processor and memory containing a rendering application.

50. 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 an image of a scene from a reference viewpoint using light field image data, where the image data comprises a plurality of images of a scene captured from different viewpoints and synthesizing the image includes creating a depth map that specifies depths from the reference viewpoint for pixels in the image;

encoding the synthesized image; and

creating an image file including the encoded image, and metadata describing the encoded image, where the metadata includes the depth map.