Multiple operating modes to expand dynamic range
Example embodiments relate to multiple operating modes to expand dynamic range. An example embodiment includes a camera system. The camera system may include a first image sensor having a first dynamic range corresponding to a first range of luminance levels in a scene. The system may also include a second image sensor having a second dynamic range corresponding to a second range of luminance levels in the scene. The camera system may further include a processor coupled to the first image sensor and the second image sensor. The processor may be configured to execute instructions to identify objects of a first type in a first image of the scene captured by the first image sensor and identify objects of a second object type in a second image of the scene captured by the second image sensor.
1. A camera system, comprising:
a first image sensor having a first dynamic range corresponding to a first range of luminance levels in a scene;
a second image sensor having a second dynamic range corresponding to a second range of luminance levels in the scene, wherein the second range of luminance levels includes luminance levels that are higher than the first range of luminance levels;
a third image sensor having a third dynamic range corresponding to a third range of luminance levels in the scene, wherein the third range of luminance levels includes at least one luminance level that is lower than the first range of luminance levels; and
a processor coupled to the first image sensor, the second image sensor, and the third image sensor, wherein the processor is configured to execute instructions to identify an object based on a first image of the scene captured by the first image sensor, a second image of the scene captured by the second image sensor, and a third image of the scene captured by the third image sensor.
2. The camera system of claim 1 ,
wherein the first image sensor has a variable exposure that is adjusted by a controller executing instructions based on illuminance, and
wherein the second image sensor has a fixed exposure.
3. The camera system of claim 2 , wherein adjusting the variable exposure based on luminance comprises adjusting an exposure duration, an aperture size, a gain level, or an ISO sensitivity of the first image sensor.
4. The camera system of claim 2 ,
wherein the variable exposure is adjusted by modifying a shutter speed or gain associated with a shutter on the first image sensor.
5. The camera system of claim 1 , wherein the second image sensor receives light from the scene via a neutral-density filter.
6. The camera system of claim 1 , wherein the third image sensor has a variable exposure that is adjusted by a controller executing instructions based on illuminance.
7. The camera system of claim 6 , wherein adjusting the variable exposure based on luminance comprises adjusting an exposure duration, shutter speed, an aperture size, or an ISO sensitivity of the third image sensor.
8. The camera system of claim 1 , further comprising:
a fourth image sensor having the first dynamic range; and
a fifth image sensor having the second dynamic range,
wherein the processor is coupled to the fourth image sensor and the fifth image sensor, and
wherein the processor is further configured to execute instructions to:
identify objects of a first object type in a fourth image of a separate perspective of the scene captured by the fourth image sensor, wherein the first object type has an expected luminance within the first range of luminance levels; and
identify objects of a second object type in a fifth image of the separate perspective of the scene captured by the fifth image sensor, wherein the second object type has an expected luminance within the second range of luminance levels.
9. The camera system of claim 1 , further comprising:
a fourth image sensor having the first dynamic range; and
a fifth image sensor having the second dynamic range,
wherein the processor is coupled to the fourth image sensor and the fifth image sensor, and
wherein the processor is further configured to execute instructions to identify the object based on a fourth image captured by the fourth image sensor and a fifth image captured by the fifth image sensor.
10. The camera system of claim 9 ,
wherein the fourth image sensor has a variable exposure that is adjusted by a controller executing instructions based on luminance, and
wherein the fifth image sensor has a fixed exposure.
11. The camera system of claim 10 , wherein adjusting the variable exposure based on luminance comprises adjusting an exposure duration, an aperture size, or an ISO sensitivity of the fourth image sensor.
12. The camera system of claim 1 , further comprising:
a first lens optically coupled to the first image sensor and having a first focal length; and
a second lens optically coupled to the second image sensor and having a second focal length,
wherein the first focal length is different than the second focal length, and
wherein, correspondingly, the first image of the scene and the second image of the scene are captured at different focal lengths.
13. The camera system of claim 1 , further comprising:
a first lens optically coupled to the first image sensor and having a first focal length; and
a second lens optically coupled to the second image sensor and having a second focal length,
wherein the first focal length is different than the second focal length,
wherein, correspondingly, the first image of the scene and the second image of the scene are captured at different focal lengths, and
wherein the processor is further configured to execute instructions to
determine a distance of the object based on:
the first focal length;
the second focal length;
a focus of the object in the first image of the scene; and
a focus of the object in the second image of the scene.
14. The camera system of claim 1 , wherein the first image and the second image are captured substantially simultaneously.
15. The camera system of claim 1 , wherein the first image sensor and the second image sensor are vertically aligned.
16. The camera system of claim 1 , wherein the camera system is mounted on an autonomous vehicle and used for object detection and avoidance.
17. A method, comprising:
capturing, by a first image sensor having a first dynamic range corresponding to a first range of luminance levels in a scene, a first image of the scene;
capturing, by a second image sensor having a second dynamic range corresponding to a second range of luminance levels in the scene, a second image of the scene, wherein the second range of luminance levels includes luminance levels that are higher than the first range of luminance levels;
capturing, by a third image sensor having a third dynamic range corresponding to a third range of luminance levels in the scene, a third image of the scene, wherein the third range of luminance levels includes at least one luminance level that is lower than the first range of luminance levels; and
identifying, by a processor coupled to the first image sensor, the second image sensor, and the third image sensor, an object based on the first image of the scene, the second image of the scene, and the third image of the scene.
18. The method of claim 17 , wherein the second image sensor receives light from the scene via a neutral-density filter.
19. A camera system comprising:
a first image sensor having a first dynamic range corresponding to a first range of luminance levels in a scene;
a second image sensor having a second dynamic range corresponding to a second range of luminance levels in the scene, wherein the second range of luminance levels includes luminance levels that are higher than the first range of luminance levels;
a third image sensor having the first dynamic range;
a fourth image sensor having the second dynamic range; and
a processor coupled to the first image sensor, the second image sensor, the third image sensor, and the fourth image sensor, wherein the processor is configured to execute instructions to identify an object based on a first image of the scene captured by the first image sensor, a second image of the scene captured by the second image sensor, a third image of the scene captured by the third image sensor, and a fourth image of the scene captured by the fourth image sensor.
20. The camera system of claim 19 , wherein the second image sensor receives light from the scene via a neutral-density filter.