Projection transformations for depth estimation

Patent metadata

Field	Value
Publication number	US-2016245641-A1
Application number	US-201514626018-A
Country	US
Kind code	A1
Filing date	Feb 19, 2015
Priority date	Feb 19, 2015
Publication date	Aug 25, 2016
Grant date	—

Abstract

An active rangefinder system disclosed herein parameterizes a set of transformations predicting different possible appearances of a projection feature projected into a three-dimensional scene. A matching module matches an image of the projected projection feature with one of the transformations, and a depth estimation module estimates a distance to an object reflecting the projection feature based on the transformation identified by the matching module.

First claim

What is claimed is:

1 . A system for estimating distance, the system comprising:
an imaging device to capture an image of a projection feature to be projected by a projector and reflected from a surface in a three-dimensional image space; an appearance transformer to parameterize a set of transformations, the transformations predicting different possible appearances of the projection feature projected onto the surface; a prediction matcher to match the captured image of the projected projection feature with a select one of the transformations; and a depth estimator to generate an estimation of distance between a projector and a surface in a three-dimensional space based at least on the select one of the transformations.

2 . The system of claim 1 wherein each transformation in the set of transformations introduces a different two-dimensional skew modeling an orientation variation of an imaging surface.

3 . The system of claim 1 wherein each transformation in the set of transformations introduces a random disparity modeling a depth variation of an imaging surface.

4 . The system of claim 1 wherein the appearance transformer applies the set of transformations to a patch of the reference image including the projection feature.

5 . The system of claim 1 wherein the prediction matcher compares the patch of the reference image to a number of patches of the captured image aligned along a same axis.

6 . The system of claim 1 wherein each transformation in the set of transformations models a different depth of an imaging surface relative to the projector.

7 . The system of claim 1 wherein the prediction matcher matches a pixel in the captured image with a pixel in a reference image, the reference image transformed by one of the transformations of the appearance transformer.

8 . A method of estimating distance, the method comprising:
parameterizing a set of transformations predicting an appearance of a projection feature projected into the image space; projecting, with the projector, the projection feature into the image space; capturing an image of the projected projection feature reflected on a surface in the image space; matching the captured image of the projected projection feature with a select one of the set of transformations; and generating an estimation of distance between a projector and a surface in a three-dimensional space based on the select one of the transformations.

9 . The method of claim 8 wherein each transformation in the set of transformations introduces a different two-dimensional skew modeling an orientation variation of an imaging surface.

10 . The method of claim 8 further comprising:
applying the set of transformations to a reference image including the projection feature.

11 . The method of claim 10 , wherein each transformation in the set of transformations models a different depth of an imaging surface relative to the projector.

12 . The method of claim 8 , wherein matching the captured image with a select one of the transformations further comprises:
matching a patch of the reference image to a number of patches of the captured image aligned along a same axis.

13 . The method of claim 8 , wherein matching the captured image of the projected projection feature with one of the transformations further includes:
matching a pixel in the captured image with a pixel in a reference image transformed by one of the transformations.

14 . The method of claim 8 , wherein each transformation in the set of transformations induces a two-dimensional skew angle to a patch in a reference image.

15 . The method of claim 8 , further comprising:
applying the set of transformations to each of a number of patches of a reference image, each of the patches including one or more different projection features; projecting the different projection features into the image space; and estimating a distance to each of the different projection features by comparing patches of the captured image to the transformed patches of the reference image.

16 . A system for estimating distance, the system comprising:
one or more processors; an appearance transformer to be executed by the one or more processors that parameterizes a set of transformations, the transformations predicting different possible appearances of the projection feature of an image projected onto a surface; a prediction matcher to be executed by the one or more processors that matches the image of the projected projection feature with a select one of the transformations; and a depth estimator to be executed by the one or more processors that generates an estimation of distance between a projector of the image and a surface in a three-dimensional space based on the select one of the transformations.

17 . The system of claim 16 wherein each transformation in the set of transformations introduces a different two-dimensional skew modeling an orientation variation of an imaging surface.

18 . The system of claim 16 wherein each transformation in the set of transformations introduces a random disparity modeling a depth variation of an imaging surface.

19 . The system of claim 16 wherein the appearance transformer applies the set of transformations to a patch of the reference image including the projection feature.

20 . The system of claim 16 wherein the prediction matcher compares the patch of the reference image to a number of patches of the image aligned along a same axis.

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Kowdle Adarsh Prakash Murthy
• Kirk Adam Garnet
• Canton Ferrer Cristian
• Whyte Oliver
• Kang Sing Bing

Classifications

• G06T2207/10048

  Infrared image · CPC title

• G06T7/0075

  Physics · mapped topic

• G01B11/026 Primary

  by measuring distance between sensor and object (G01B11/0608 takes precedence) · CPC title

• G06T7/74 Primary

  involving reference images or patches · CPC title

• G06T2207/20021

  Dividing image into blocks, subimages or windows · CPC title