Lightweight cross reality device with passive depth extraction
A wearable display system including multiple cameras and a processor is disclosed. A greyscale camera and a color camera can be arranged to provide a central view field associated with both cameras and a peripheral view field associated with one of the two cameras. One or more of the two cameras may be a plenoptic camera. The wearable display system may acquire light field information using the at least one plenoptic camera and create a world model using the first light field information and first depth information stereoscopically determined from images acquired by the greyscale camera and the color camera. The wearable display system can track head pose using the at least one plenoptic camera and the world model. The wearable display system can track objects in the central view field and the peripheral view fields using the one or two plenoptic cameras, when the objects satisfy a depth criterion.
1. A wearable display system, the wearable display system comprising:
a headset comprising one first camera with a global shutter and one second camera with a rolling shutter, the first camera and the second camera positioned so as to provide overlapping views of a central view field; and
a processor operatively coupled to the first camera and the second camera and configured to:
perform a compensation routine to adjust images acquired using the second camera for rolling shutter image distortion;
create a world model using, in part, depth information stereoscopically determined from images acquired using the first camera and the adjusted images; and
disable the second camera or modulate a frame rate of the second camera based on at least one of a power conservation criterion or a world model completeness criterion.
2. The wearable display system of claim 1 , wherein the first camera and the second camera are asymmetrically angled inward.
3. The wearable display system of claim 2 , wherein a field of view of the first camera is larger than a field of view of the second camera.
4. The wearable display system of claim 2 , wherein the first camera is angled inwards between 20 and 40 degrees and the second camera is angled inwards between 1 and 20 degrees.
5. The wearable display system of claim 1 , wherein the first camera has an angular pixel resolution between 1 and 5 arcminutes per pixel.
6. The wearable display system of claim 1 , wherein the processor is further configured to perform a size reduction routine to adjust images acquired using the second camera.
7. The wearable display system of claim 6 , wherein the size reduction routine includes generating reduced size images by binning pixels in the images acquired by the second camera.
8. The wearable display system of claim 1 , wherein:
the compensation routine comprises:
comparing a first image acquired using the first camera to a second image acquired using the second camera to detect a skew in at least part of the second image; and
adjusting the at least part of the second image to compensate for the detected skew.
9. The wearable display system of claim 8 , wherein:
comparing the first image acquired using the first camera to the second image acquired using the second camera comprises performing a line-by-line comparison between a first image obtained by the first camera and a second image obtained by the second camera.
10. The wearable display system of claim 1 , wherein:
the processor is further configured to:
maintain the second camera in a disabled or modulated frame rate state until the processor detects a condition indicating that the world model is to be updated.
11. The wearable display system of claim 1 , wherein:
at least one of the first camera or the second camera comprises a plenoptic camera; and
the processor is further configured to:
create a world model using, in part, light field information acquired by the at least one of the first camera or the second camera.
12. The wearable display system of claim 1 , wherein:
the first camera comprises a plenoptic camera; and
the processor is further configured to:
perform a world model update routine using depth information acquired using the plenoptic camera.
13. The wearable display system of claim 1 , wherein the processor is mechanically coupled to the headset.
14. The wearable display system of claim 1 , wherein the headset comprises a display device mechanically coupled to the processor.
15. The wearable display system of claim 1 , wherein a local data processing module comprises the processor, the local data processing module operatively coupled to a display device through a communication link, and wherein the headset comprises the display device.
16. A method of creating a world model using a wearable display system, the wearable display system comprising:
a headset comprising one first camera with a global shutter and one second camera with a rolling shutter, the first camera and the second camera positioned so as to provide overlapping views of a central view field; and
a processor operatively coupled to the first camera and the second camera;
wherein the method comprises using the processor to:
perform a compensation routine to adjust images acquired using the second camera for rolling shutter image distortion;
create the world model using, in part, depth information stereoscopically determined from images acquired using the first camera and the adjusted images; and
disable the second camera or modulate a frame rate of the second camera based on at least one of a power conservation criterion or a world model completeness criterion.
17. The method of claim 16 , wherein the method comprises using the processor to perform a size reduction routine to adjust images acquired using the second camera.
18. The method of claim 17 , wherein the size reduction routine includes generating reduced size images by binning pixels in the images acquired by the second camera.
19. The method of claim 16 , wherein:
the compensation routine comprises:
comparing a first image acquired using the first camera to a second image acquired using the second camera to detect a skew in at least part of the second image; and
adjusting the at least part of the second image to compensate for the detected skew.
20. The method of claim 19 , wherein:
comparing the first image acquired using the first camera to the second image acquired using the second camera comprises performing a line-by-line comparison between a first image obtained by the first camera and a second image obtained by the second camera. the second camera.