METHOD FOR ESTIMATING EGO MOTION OF AN OBJECT

• US 20150086078A1
• Filed: 08/15/2014
• Published: 03/26/2015
• Est. Priority Date: 09/20/2013
• Status: Active Grant

• Current Assignee: Application Solutions (Electronics And Vision) Limited (Continental AG)
• Original Assignee: Application Solutions (Electronics And Vision) Limited (Continental AG)
• Inventors: Sibiryakov, Alexander
• Granted Patent: US 9,158,977 B2
• Time in Patent Office: Days
• US Class Current: 382/104
• CPC Class Codes: G06F 18/22 Matching criteria, e.g. proximity measures
• CPC Class Codes: G06T 11/60 Editing figures and text; Combining figures or text
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20056 Discrete and fast Fourier transform, [DFT, FFT]
• CPC Class Codes: G06T 2207/20068 Projection on vertical or horizontal image axis
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 3/4038 Image mosaicing, e.g. composing plane images from plane sub-images
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: G06T 7/223 using block-matching
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: G06T 7/262 using transform domain methods, e.g. Fourier domain methods
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle

Abstract

A method for estimating ego motion of an object moving on a surface, the method including generating at least two composite top view images of the surface on the basis of video frames provided by at least one onboard video camera of the object moving on the surface; performing a region matching between consecutive top view images to extract global motion parameters of the moving object; calculating the ego motion of the moving object from the extracted global motion parameters of the moving object.

Claims

1. A method for estimating ego motion of an object moving on a surface,

the method comprising:

(a) generating at least two composite top view images of the surface on the basis of video frames provided by at least one onboard video camera of said object moving on said surface;

(b) performing a region matching between consecutive top view images to extract global motion parameters of said moving object;

(c) calculating the ego motion of said moving object from the extracted global motion parameters of said moving object.

2. The method according to claim 1,

wherein said region matching between consecutive top view images comprises feature matching or block matching.

3. The method according to claim 1,

wherein the top view images are processed by performing a 1D integral transformation to provide 1D integral images used for the region matching.

4. The method according to claim 1,

wherein the extracted global motion parameters of said moving object comprise a translation and a rotation of the moving object.

5. The method according to claim 1,

wherein a motion of a feature on a top view image is decomposed into a sum of a global translation vector estimated from a large top view region and a local translation vector estimated from a small region around the respective feature.

6. The method according to claim 1,

wherein the top view image is formed by a metric top view image of the surface constructed by a regular grid with a predetermined distance between samples on the surface and by projecting each sample into a camera image to obtain a pixel value.

7. The method according to claim 1,

wherein the global motion parameters are computed from a set of inliers provided by said region matching and selected by an estimator.

8. The method according to claim 1,

wherein the object is formed by a vehicle moving on a flat surface.

9. An apparatus for estimation of ego motion of an object moving on a surface comprising

at least one onboard video camera attached to said object adapted to provide video frames of the surface;

a generation unit adapted to generate composite top view images of the surface on the basis of video frames;

a region matching unit adapted to perform a region matching between consecutive top view images to extract global motion parameters of said moving object; and

a calculation unit adapted to calculate the ego motion of said moving object from the extracted global motion parameters of said moving object.

10. The apparatus according to claim 9 further comprising a transformation unit adapted to perform a 1D integral transformation of the top view images to provide 1D integral images stored in a buffer to be used for the region matching by said region matching unit.

11. The apparatus according to claim 9,

wherein the global motion parameters are computed from a set of inliers provided by said region matching performed by said region matching unit and selected by an estimator.

12. The apparatus according to claim 11,

wherein the estimator is a RANSAC estimator.

13. The apparatus according to claim 9,

wherein the onboard video cameras are monocular cameras.

14. A vehicle moveable on a surface comprising an apparatus according to claim 9.

15. The vehicle according to claim 14,

wherein the vehicle comprises a car moving on a road surface or a robot moving on a flat surface.