Stereo viewing

Patent metadata

Field	Value
Publication number	US-10455221-B2
Application number	US-201515302123-A
Country	US
Kind code	B2
Filing date	Mar 19, 2015
Priority date	Apr 7, 2014
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

The invention relates to creating and viewing stereo images, for example stereo video images, also called 3D video. At least three camera sources with overlapping fields of view are used to capture a scene so that an area of the scene is covered by at least three cameras. At the viewer, a camera pair is chosen from the multiple cameras to create a stereo camera pair that best matches the location of the eyes of the user if they were located at the place of the camera sources. That is, a camera pair is chosen so that the disparity created by the camera sources resembles the disparity that the user's eyes would have at that location. If the user tilts his head, or the view orientation is otherwise altered, a new pair can be formed, for example by switching the other camera. The viewer device then forms the images of the video frames for the left and right eyes by picking the best sources for each area of each image for realistic stereo disparity.

First claim

The invention claimed is:

1. A method, comprising:
decoding both active and passive source video signals that have been differently encoded according to a viewing angle of a user with a visible region that was captured by one or more active image sources being encoded in higher quality than one or more regions not currently visible that were captured by one or more passive image sources,
determining head orientation of a user to obtain a first head orientation,
selecting a first image source, a second image source and a third image source, from three or more image sources, based on said first head orientation, said first and second image source forming a stereo image source,
rendering a first target image for one eye of the user using decoded video signals from said first image source and a second target image for another eye of the user using decoded video signals from said second image source,
determining head orientation of said user to obtain a second head orientation,
selecting said second image source and the third image source based on said second head orientation, said second and third image source forming a stereo image source,
rendering a third target image for one eye of the user using decoded video signals from said second image source and a fourth target image for another eye of the user using decoded video signals from said third image source,
stitching at least a part of an image from the third image source with at least one of the first target image and the second target image, and
stitching at least a part of an image from the third image source with at least one of the third target image and the fourth target image.

2. An apparatus comprising at least one processor, and memory including computer program code, the memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least:
decode both active and passive source video signals that have been differently encoded according to a viewing angle of a user with a visible region that was captured by one or more active image sources being encoded in higher quality than one or more regions not currently visible that were captured by one or more passive image sources,
determine head orientation of a user to obtain a first head orientation,
select a first image source, a second image source and a third image source, from three or more image sources, based on said first head orientation, said first and second image source forming a stereo image source,
render a first target image for one eye of the user using decoded video signals from said first image source and a second target image for another eye of the user using decoded video signals from said second image source,
determine head orientation of said user to obtain a second head orientation,
select said second image source and the third image source based on said second head orientation, said second and third image source forming a stereo image source,
render a third target image for one eye of the user using decoded video signals from said second image source and a fourth target image for another eye of the user using decoded video signals from said third image source,
stitch at least a part of an image from the third image source with at least one of the first target image and the second target image, and
stitch at least a part of an image from the third image source with at least one of the third target image and the fourth target image.

3. An apparatus according to claim 2 , comprising computer program code to cause the apparatus to:
form color values of a first region of pixels corresponding to a first region of a scene using said first image source, said color values of said first region of pixels being used for forming said first target image for displaying to a first eye,
form color values of a second region of pixels corresponding to said first region of a scene using said second image source, said color values of said second region of pixels being used for forming said second target image for displaying to a second eye,
form color values of a third region of pixels corresponding to said first region of a scene using said third image source, said color values of said third region of pixels being used for forming said third target image for displaying to said first eye,
form color values of a fourth region of pixels corresponding to said first region of a scene using said second image source, said color values of said fourth region of pixels being used for forming said fourth target image for displaying to said second eye.

4. An apparatus according to claim 3 , comprising computer program code to cause the apparatus to:
determine locations of a first and a second virtual eye corresponding to said eyes of the user in a coordinate system using said head orientations,
select said image sources based on said locations of said virtual eyes with respect to image source locations in said coordinate system.

5. An apparatus according to claim 4 , comprising computer program code to cause the apparatus to:
determine an image source for a pixel of an image for a first eye of the user to be a close image source that satisfies a closeness criterion to a virtual eye corresponding to said first eye, where said close image source captures the scene portion corresponding to the pixel, and
determine an image source for a pixel of an image for said first eye of the user to be another source than the close image source to said virtual eye corresponding to said first eye, where the close image source does not capture the scene portion corresponding to the pixel.

6. An apparatus according to claim 2 , comprising computer program code to cause the apparatus to:
render regions of an image for an eye so that the regions correspond to image sources, wherein the regions are rendered in order of closeness of the image sources to a virtual eye corresponding to said eye in image source coordinate system.

7. An apparatus according to claim 6 , comprising computer program code to cause the apparatus to:
combine the regions of said image together at their edges by using an image stitching technique.

8. An apparatus according to claim 7 , comprising computer program code to cause the apparatus to:
combine said regions of said images by blending the edge areas of the regions.

9. An apparatus according to claim 2 , comprising computer program code to cause the apparatus to:
blend a temporal transition from said image formed using said first image source and said image using said third image source.

10. An apparatus according to claim 9 , comprising computer program code to cause the apparatus to:
adjust the duration of the temporal transition blending by using information on head movement speed.

11. An apparatus according to claim 2 , comprising computer program code to cause the apparatus to:
determine audio information for the left ear and audio information for the right ear using said head orientation information to modify audio information from two or more audio sources using a head-related transfer function.

12. An apparatus according to claim 2 , comprising computer program code to cause the apparatus to:
determine source orientation information for said image sources, and
use said source orientation information together with said head orientation information for selecting said image sources.

13. An apparatus according to claim 11 , comprising computer program code to cause the apparatus to:
determine source orientation information for said audio sources, and
use said source orientation information together with said head orientation information for modifying audio i

Assignees

• Nokia Technologies Oy

Inventors

• Gronholm Kim
• Baldwin Andrew Robert

Classifications

• G02B30/34

  Stereoscopes providing a stereoscopic pair of separated images corresponding to parallactically displaced views of the same object, e.g. three-dimensional [3D] slide viewers · CPC title

• H04N19/17

  the unit being an image region, e.g. an object · CPC title

• H04N19/162

  User input · CPC title

• H04N13/383

  for tracking with gaze detection, i.e. detecting the lines of sight of the viewer's eyes · CPC title

• G03B37/04

  with cameras or projectors providing touching or overlapping fields of view · CPC title