Exterior environment recognition device and exterior environment recognition method

1. An exterior environment recognition device comprising semiconductor circuitry configured to:

obtain an image in a detection area;

generate a portion group by grouping, based on a first relative relationship between or among portions, multiple portions in an area extending from a plane corresponding to a road surface to a predetermined height in the obtained image; and

divide the portion group into two in a horizontal direction of the image, and determines, based on a second relative relationship between two divided portion groups, whether the portion group is a first person candidate which is a candidate of a person, wherein

the second relative relationship is whether or not each central line angle formed by a vertical line and a central line of each of the two divided portion groups is included in a predetermined first angle range.

2. The exterior environment recognition device according to claim 1 , wherein the first relative relationship is any one of a relative position relationship, a difference of luminance, or continuity in an edge direction.

3. The exterior environment recognition device according to claim 1 , wherein the second relative relationship is one or more relationships selected from a group including a shape, a size of area, symmetry, and luminance.

4. The exterior environment recognition device according to claim 1 , wherein the semiconductor circuitry is further configured to:

divide, into multiple areas in a height direction, the area extending from the plane corresponding to the road surface to the predetermined height in the image, and groups multiple portions in each of the areas divided; and

determine the first person candidate when the second relative relationship between the two divided portion groups is satisfied and a difference angle between central lines of the grouped portion groups adjacent to each other in the height direction is equal to or more than a predetermined second angle range.

5. The exterior environment recognition device according to claim 4 , wherein when a difference angle formed by any one of the areas in the height direction is determined not to be equal to or more than the predetermined second angle range, the semiconductor circuitry is configured not to execute determination of the first person candidate concerning the remaining areas.

6. The exterior environment recognition device according to claim 1 , wherein the semiconductor circuitry is further configured to change the first angle range according to a relative distance between a subject vehicle and the portion group.

7. The exterior environment recognition device according to claim 1 , wherein the semiconductor circuitry includes a processor and a memory storing a program for the processor.

8. An exterior environment recognition device comprising semiconductor circuitry configured to:

obtain an image in a detection area;

generate a portion group by grouping, based on a first relative relationship between or among portions, multiple portions in an area extending from a plane corresponding to a road surface to a predetermined height in the obtained image; and

divide the portion group into two in a horizontal direction of the image, and determines, based on a second relative relationship between two divided portion groups, whether the portion group is a first person candidate which is a candidate of a person;

track the portion group determined to be the first person candidate;

measure a number of times of reverses when it is determined that the portion group tracked is the first person candidate and has not been the first person candidate; and

specify the first person candidate as a second person candidate when the number of times of reverses is determined to be equal to or more than the predetermined range of the number of times.

9. An exterior environment recognition device comprising semiconductor circuitry configured to:

obtain an image in a detection area;

generate a portion group by grouping, based on a first relative relationship between or among portions, multiple portions in an area extending from a plane corresponding to a road surface to a predetermined height in the obtained image; and

divide the portion group into two in a horizontal direction of the image, and determines, based on a second relative relationship between two divided portion groups, whether the portion group is a first person candidate which is a candidate of a person;

track the portion group determined to be the first person candidate;

measure a reverse cycle when is determined that the portion group tracked is the first person candidate and has not been the first person candidate; and

determine that the first person candidate is moving when a reverse cycle is determined to be equal to or more than a predetermined cycle range.