Blending depth images obtained with multiple exposures
AssigneeAnalog Devices, Inc.
InventorRick Haltmaier
Life of this patent
Estimating the term…
Abstract
To extend dynamic range, a depth imager can expose a scene with two different exposures to obtain two depths. The two different exposures are selected to have respective depth ranges that overlap each other. The two depths can be combined by taking into account the difference in exposures and where the two depths are located with respect to boundaries of an overlapping range of the two depth ranges. The combination of the two depths in this manner can help avoid image artifacts such as contouring.
Claims23
A method for extending dynamic range of a depth imager through multiple exposures, the method comprising:
- determining a first depth obtained from a first exposure of a scene;
- determining a second depth obtained from a second exposure of the scene, wherein the second exposure is different from the first exposure;
- computing an estimated depth based on the first depth, the second depth, and a relationship between the first exposure and the second exposure;
- and
- computing an adjusted depth based on the estimated depth, the relationship between the first exposure and the second exposure, a saturation distance of the second exposure, and a noise tolerance distance of the first exposure.
A depth imager with extended dynamic range, the depth imager comprising:
- a time-of-flight controller to control a light source and one or more sensors to make a first measurement based on a first exposure of a scene and a second measurement based on a second exposure of the scene different from the first exposure;
- a depth calculator to calculate a first depth based on the first measurement and a second depth based on the second measurement;
- and
- a blender to:
- compute an estimated depth based on the first depth and the second depth;
- and
- output an adjusted depth based on the first depth, the second depth, an exposure weight relating the first exposure and the second exposure, and an interpolation weight computed based on the estimated depth.
A depth imager with extended dynamic range, the depth imager comprising:
- means for making a first measurement from exposing a scene with a first number of light pulses and a second measurement from exposing the scene with a second number of light pulses;
- means for determining a first depth from the first measurement and a second depth from the second measurement;
- means for determining an estimated depth based on the first depth and the second depth;
- and
- means for outputting an adjusted depth by blending the first depth and the second depth with a combination of (1) an exposure weight relating the first number of light pulses and the second number of light pulses, and (2) an interpolation weight, wherein the interpolation weight is determined based on the estimated depth.
Dependencies are inferred from the claim text.