OBJECT DETECTION DEVICE

• US 20120027258A1
• Filed: 04/22/2010
• Published: 02/02/2012
• Est. Priority Date: 04/23/2009
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Uchida, Naohide, Shiraishi, Tatsuya, Nishijima, Masakazu, Nanami, Takeshi, Goto, Hiroki
• Granted Patent: US 9,053,554 B2
• Time in Patent Office: Days
• US Class Current: 382/103
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30261 Obstacle
• 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: G06V 20/58 Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads

Abstract

An object detection device including: an imaging unit (11) carried on a movable body; a first calculation unit (21; 22; 23) that calculate an observed value of an image displacement among a plurality of images captured by the imaging unit (11) at respective different timings; a first object detection unit (10, 21; 10, 22; 10, 23) that detects an object candidate and acquires information of the object candidate; a second calculation unit (21, 22, 23) that calculates a theoretic value of the image displacement on the basis of the information of the object candidate; and a second object detection unit (21; 22; 23) that compares the observed value of the image displacement and the theoretic value of the image displacement and determines whether the object candidate is an object on the basis of the comparison result.

Claims

1. An object detection device comprising:

an imaging unit carried on a movable body;

a first calculation unit that calculate an observed value of an image displacement among a plurality of images captured by the imaging unit at respective different timings;

a first object detection unit that detects an object candidate and acquires information of the object candidate;

a second calculation unit that calculates a theoretic value of the image displacement on the basis of the information of the object candidate; and

a second object detection unit that compares the observed value of the image displacement and the theoretic value of the image displacement and determines whether the object candidate is an object on the basis of the comparison result.

2. The object detection device according to claim 1, wherein

the information of the object candidate is at least one of a distance between the object candidate and the movable body and a relative velocity of the object candidate with respect to the movable body.

3. The object detection device according to claim 1, wherein

the second calculation unit calculates the theoretic value of the image displacement corresponding to the object candidate.

4. The object detection device according to claim 3, wherein

the second calculation unit calculates the theoretic value of the image displacement of a point that is located at a distance equal to a distance between the object candidate and the movable body.

5. The object detection device according to claim 1, wherein

the second object detection unit calculates a difference value between the observed value of the image displacement and the theoretic value of the image displacement for each of a plurality of segments on the image and determines whether the object candidate is the object on the basis of a segment for which the difference value is equal to or less than a first threshold.

6. The object detection device according to claim 5, wherein

the second object detection unit determines that the object candidate is the object if a ratio of the segment for which the difference value is equal to or less than the first threshold is equal to or greater than a predetermined ratio.

7. The object detection device according to claim 1, wherein

the second object detection unit calculates a difference value between the observed value of the image displacement and the theoretic value of the image displacement for each of a plurality of segments on the image, calculates an average value of the difference values of the plurality of segments, and determines whether the object candidate is the object on the basis of the difference value and the average value of the difference values.

8. The object detection device according to claim 7, wherein

the second object detection unit calculates a corrected difference value by subtracting the average value from the difference value and determines whether the object candidate is the object on the basis of a segment for which the corrected difference value is equal to or less than a second threshold.

9. The object detection device according to claim 1, wherein

the second object detection unit calculates difference values between the observed value of the image displacement and the theoretic value of the image displacement for each of a plurality of segments on the image and determines whether the object candidate is the object on the basis of a degree of change, with respect to change of positions on the image, of the difference values for each of the plurality of segments.

10. The object detection device according to claim 9, wherein

the degree of change is a slope of a straight line that fits to the difference values.

11. The object detection device according to claim 10, wherein

the second object detection unit determines that the object candidate is the object if an absolute value of the slope of the straight line is equal to or less than the third threshold.

12. The object detection device according to claim 1, further comprising:

a turning state detection unit that detects a turning state of the movable body; and

a correction unit that corrects the theoretic value of the image displacement on the basis of the turning state of the movable body, wherein

the second detection unit compares, for each of a plurality of segments on the image, the observed value of the image displacement with a corrected theoretic value of the image displacement, which has been corrected by the correction unit, and determines whether the object candidate is the object on the basis of the comparison result.

13. The object detection device according to claim 5, wherein the segment corresponds to a feature point.

14. The object detection device according to claim 5, wherein the plurality of segments is included in a processing region that is set in accordance with a position of the object candidate.

15. The object detection device according to claim 7, wherein the segment corresponds to a feature point.

16. The object detection device according to claim 7, wherein the plurality of segments is included in a processing region that is set in accordance with a position of the object candidate.

17. The object detection device according to claim 9, wherein the segment corresponds to a feature point.

18. The object detection device according to claim 9, wherein the plurality of segments is included in a processing region that is set in accordance with a position of the object candidate.