Pedestrian detection apparatus and pedestrian detection method
A target pedestrian who is present within a range of a predetermined distance from a roadway is detected. Whether or not the target pedestrian has gazed at a crossing destination and whether or not the target pedestrian has performed a safety confirmation regarding vehicles traveling on the roadway are determined based on a gaze direction of the target pedestrian. As a result, when the target pedestrian has performed one action of either of gazing at the crossing destination and the safety confirmation, and then performed the other action within a predetermined amount of time, the target pedestrian is detected as a pre-crossing pedestrian who has an intention to cross the roadway. Consequently, a pedestrian who is attempting to cross the roadway can be accurately detected at a stage before the pedestrian actually starts crossing.
1. A pedestrian detection apparatus that analyzes a captured image acquired from an onboard camera and thereby detects a pedestrian who appears in the captured image, the pedestrian detection apparatus comprising:
a roadway detecting unit that detects, using one or more processors, a roadway in the captured image;
a target pedestrian detecting unit that detects, using at least one of the one or more processors, a pedestrian who is present within a range of a predetermined distance in both side directions from the roadway in the captured image as a target pedestrian;
a gaze direction acquiring unit that acquires, using at least one of the one or more processors, information on a gaze direction of the target pedestrian;
a gaze determining unit that determines, using at least one of the one or more processors, that the target pedestrian has gazed at a crossing destination that is present on an other side of the roadway, when a condition in which the gaze direction of the target pedestrian is fixed in a direction of the crossing destination that is present on the other side of the roadway is continued for a predetermined gaze time;
a safety confirmation determining unit that determines, using at least one of the one or more processors, whether the target pedestrian has performed a safety confirmation regarding vehicles traveling on the roadway, based on the gaze direction of the target pedestrian; and
a pre-crossing pedestrian detecting unit that detects, using at least one of the one or more processors, the target pedestrian who has performed one action of either of gazing at the crossing destination that is present on the other side of the roadway and the safety confirmation, and then performed the other action within a predetermined amount of time as a pre-crossing pedestrian who has an intention to cross the roadway.
2. The pedestrian detection apparatus according to claim 1 , wherein:
the pre-crossing pedestrian detecting unit detects, as the pre-crossing pedestrian, the target pedestrian who has performed the safety confirmation within a first predetermined amount of time after gazing at the crossing destination or has gazed at the crossing destination with a second predetermined amount of time that is shorter than the first predetermined amount of time after performing the safety confirmation.
3. The pedestrian detection apparatus according to claim 2 , wherein:
the gaze direction acquiring unit acquires the information on the gaze direction of the target pedestrian by analyzing an image of the target pedestrian appearing in the captured image.
4. The pedestrian detection apparatus according to claim 1 , wherein:
the gaze determining unit determines that the target pedestrian is not gazing at the crossing destination when the gaze direction of the target pedestrian is not within an angular range that is within 45 degrees from a direction perpendicular to the roadway.
5. The pedestrian detection apparatus according to claim 4 , wherein:
the gaze determining unit determines that the target pedestrian is not gazing at the crossing destination when the gaze direction of the target pedestrian is facing upward at a predetermined upper-limit angle or greater in relation to a horizontal direction.
6. The pedestrian detection apparatus according to claim 5 , wherein:
the gaze determining unit determines that the target pedestrian is not gazing at the crossing destination when the gaze direction of the target pedestrian is facing downward at a predetermined lower-limit angle or greater in relation to a horizontal direction.
7. The pedestrian detection apparatus according to claim 6 , wherein:
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction of the target pedestrian moves in one direction along a side of the roadway in relation to the target pedestrian over a predetermined angle or greater within a predetermined movement speed range.
8. The pedestrian detection apparatus according to claim 7 , further comprising:
a vehicle detecting unit that detects a vehicle that is traveling on the roadway, wherein
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding the vehicle when the gaze direction of the target pedestrian moves together with a movement of the vehicle that is traveling on the roadway.
9. The pedestrian detection apparatus according to claim 8 , wherein
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction of the target pedestrian moves in one direction of either of left and right when facing the roadway and subsequently moves in the other direction.
10. The pedestrian detection apparatus according to claim 9 , wherein:
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction when the gaze direction of the target pedestrian faces one of either of the left and right and the gaze direction when the gaze direction faces the other are separated by 90 degrees or greater.
11. The pedestrian detection apparatus according to claim 10 , wherein:
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction of the target pedestrian moves from a direction along the roadway to a direction no longer orthogonal to the roadway, via the direction orthogonal to the roadway.
12. The pedestrian detection apparatus according to claim 1 , wherein:
the gaze direction acquiring unit acquires the information on the gaze direction of the target pedestrian by analyzing an image of the target pedestrian appearing in the captured image.
13. The pedestrian detection apparatus according to claim 4 , wherein:
the gaze determining unit determines that the target pedestrian is not gazing at the crossing destination when the gaze direction of the target pedestrian is facing upward at a predetermined upper-limit angle or greater in relation to a horizontal direction.
14. The pedestrian detection apparatus according to claim 4 , wherein:
the gaze determining unit determines that the target pedestrian is not gazing at the crossing destination when the gaze direction of the target pedestrian is facing downward at a predetermined lower-limit angle or greater in relation to a horizontal direction.
15. The pedestrian detection apparatus according to claim 1 , wherein:
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction of the target pedestrian moves in one direction along a side of the roadway in relation to the target pedestrian over a predetermined angle or greater within a predetermined movement speed range.
16. The pedestrian detection apparatus according to claim 1 , wherein
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction of the target pedestrian moves in one direction of either of left and right when facing the roadway and subsequently moves in the other direction.
17. The pedestrian detection apparatus according to claim 1 , wherein:
the safety confirmation determining unit determines that the target pedestrian has performed the safety confirmation regarding vehicles traveling on the roadway when the gaze direction of the target pedestrian moves from a direction along the roadway to a direction no longer orthogonal to the roadway, via the direction orthogonal to the roadway.
18. A pedestrian detection method for analyzing a captured image acquired from an onboard camera and thereby detecting a pedestrian who appears in the captured image, the pedestrian detection method comprising:
detecting a roadway in the captured image;
detecting a pedestrian who is present within a range of a predetermined distance in both side directions from the roadway in the captured image as a target pedestrian;
acquiring information on a gaze direction of the target pedestrian;
determining that the target pedestrian has gazed at a crossing destination that is present on an other side of the roadway, when a condition in which the gaze direction of the target pedestrian is fixed in a direction of the crossing destination that is present on the other side of the roadway is continued for a predetermined gaze time;
determining whether the target pedestrian has performed a safety confirmation regarding vehicles traveling on the roadway, based on the gaze direction of the target pedestrian; and
detecting the target pedestrian who has performed one action of either of gazing at the crossing destination that is present on the other side of the roadway and the safety confirmation, and then performed the other action within a predetermined amount of time as a pre-crossing pedestrian who has an intention to cross the roadway.