US 9,811,747 B2
Traffic light detecting device and traffic light detecting method
Takahiko Oki, Kanagawa (JP); and Hidekazu Nishiuchi, Kanagawa (JP)
Assigned to Nissan Motor Co., Ltd., Yokohama-shi, Kanagawa (JP)
Appl. No. 15/122,549
Filed by Nissan Motor Co., Ltd., Yokohama-Shi, Kanagawa (JP)
PCT Filed Mar. 10, 2014, PCT No. PCT/JP2014/056196
§ 371(c)(1), (2) Date Aug. 30, 2016,
PCT Pub. No. WO2015/136602, PCT Pub. Date Sep. 17, 2015.
Prior Publication US 2017/0103274 A1, Apr. 13, 2017
Int. Cl. H04N 7/18 (2006.01); G06K 9/00 (2006.01)
CPC G06K 9/00825 (2013.01) [H04N 7/183 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A traffic light detecting device comprising:
a camera mounted on a vehicle and configured to capture an image of surroundings of the vehicle; and
a traffic light detecting circuit configured to detect a traffic light from the image, wherein
the traffic light detecting circuit includes:
a reference signal generating unit configured to set reference signals the number of which is a multiple of three, and phases of which are shifted each other by a time obtained by dividing a cycle of an alternating current power supplied to the traffic light by the multiple of three,
a phase adjusting unit configured to select, from the reference signals the number of which is the multiple of three, a reference signal having a phase closest to a phase of the alternating current power, and adjust the phase of the reference signal to the phase of the alternating current power,
a synchronized pixel extracting unit configured to extract from the image a synchronized pixel with a luminance which varies in synchronization with the reference signal having the phase adjusted to the phase of the alternating current power, and
a traffic light judging unit configured to judge from the synchronized pixel whether or not the traffic light is present.