In-vehicle camera system and image processing apparatus
Automatic exposure control of an in-vehicle camera is performed under dark driving environments such as at night. An in-vehicle camera system includes a vehicle camera mounted in a vehicle configured to capture surroundings of the vehicle, and control circuitry that controls an exposure level of an image captured by the vehicle camera, the control of the exposure level being based on brightness information of a detection area set within the image, the detection area being a portion of the captured image and configured to output the image having exposure control performed thereon to a display.
1. An image processing apparatus, comprising:
control circuitry configured to:
receive an image of surroundings of a first vehicle, wherein the image processing apparatus is in the first vehicle;
determine an evaluation value based on a maximum value in a brightness horizontal profile and a local minimum value in the brightness horizontal profile;
detect lights of a second vehicle within a portion of the received image based on an interval between two adjacent local maximum values and an average of the two adjacent local maximum values, wherein the average is larger than the local minimum value; and
execute, based on the determined evaluation value, at least one of exposure time control or gain control, wherein
the local minimum value is between the two adjacent local maximum values in the brightness horizontal profile,
the brightness horizontal profile is based on the portion of the received image,
the second vehicle is different from the first vehicle, and
the lights of the second vehicle are displayed separately on a display screen.
2. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to:
detect the lights of the second vehicle within the portion of the received image; and
execute, based on a presence of the lights of the second vehicle within the portion of the received image, the at least one of the exposure time control or the gain control.
3. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to detect, based on the local minimum value between the two adjacent local maximum values in the brightness horizontal profile, the lights of the second vehicle within the portion of the received image.
4. The image processing apparatus according to claim 1 , wherein
the control circuitry is further configured to set the portion of the received image based on a relation of a position of a vanishing point with a reference point in the received image, and
the vanishing point is a point on a road at which ridge lines of the road cross.
5. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to execute the at least one of the exposure time control or the gain control based on a distance of peaks of two adjacent maximum values in the brightness horizontal profile.
6. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to execute the at least one of the exposure time control or the gain control based on environmental conditions associated with the surroundings of the first vehicle.
7. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to execute the at least one of the exposure time control or the gain control based on a type of a road on which the first vehicle is driven.
8. The image processing apparatus according to claim 7 , wherein the control circuitry is further configured to detect the type of the road based on position information of the first vehicle.
9. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to execute the at least one of the exposure time control or the gain control based on an average vehicle velocity on a road on which the first vehicle is driven.
10. The image processing apparatus according to claim 1 , wherein
in the exposure time control, the control circuitry is further configured to control an exposure time of an imaging sensor based on the determined evaluation value, and
in the gain control, the control circuitry is further configured to control a gain of the imaging sensor based on the determined evaluation value.
11. The image processing apparatus according to claim 1 , wherein
in the at least one of the exposure time control or the gain control, the control circuitry is further configured to notify a driver with an alarm.
12. The image processing apparatus according to claim 1 , wherein the control circuitry is further configured to execute, based on a shape of the brightness horizontal profile, the at least one of the exposure time control or the gain control.
13. An image processing method, comprising:
receiving an image of surroundings of a first vehicle;
determining an evaluation value based on a maximum value in a brightness horizontal profile and a local minimum value in the brightness horizontal profile;
detecting lights of a second vehicle within a portion of the received image based on an interval between two adjacent local maximum values and an average of the two adjacent local maximum values, wherein the average is larger than the local minimum value; and
executing, based on the determined evaluation value, at least one of exposure time control or gain control, wherein
the local minimum value is between the two adjacent local maximum values in the brightness horizontal profile,
the brightness horizontal profile is based on the portion of the received image,
the second vehicle is different from the first vehicle, and
the lights of the second vehicle are displayed separately on a display screen.