Use of a Reference Image to Detect a Road Obstacle

Abstract

Methods and systems for use of a reference image to detect a road obstacle are described. A computing device configured to control a vehicle, may be configured to receive, from an image-capture device, an image of a road on which the vehicle is travelling. The computing device may be configured to compare the image to a reference image; and identify a difference between the image and the reference image. Further, the computing device may be configured to determine a level of confidence for identification of the difference. Based on the difference and the level of confidence, the computing device may be configured to modify a control strategy associated with a driving behavior of the vehicle; and control the vehicle based on the modified control strategy.

1 . A method, comprising:
 capturing a first image of a road from a first camera pose, wherein the first image includes background objects including at least one of: a traffic sign, a building, or a lane marker;   capturing, by a camera system of a vehicle, a second image of the road from a second camera pose, wherein the second image is captured while the camera system is moving;   comparing the first image to the second image to determine one or more foreground objects, wherein the one or more foreground objects comprise at least one of: a moving object, an obstacle, or a road change; and   based on the comparing, controlling the vehicle to navigate around the foreground object.   
     
     
         2 . The method of  claim 1 , wherein the first camera pose and second camera pose differ based on a movement of the vehicle. 
     
     
         3 . The method of  claim 1 , wherein the first image is captured by a camera on a first vehicle and the second image is captured by a camera on a second vehicle. 
     
     
         4 . The method of  claim 1 , wherein controlling the vehicle to navigate around the foreground object comprises at least one of: causing the vehicle to reduce speed, causing the vehicle to change lanes, causing the vehicle to change lanes, or causing the vehicle to follow another vehicle while keeping a predetermined safe distance. 
     
     
         5 . The method of  claim 1 , wherein controlling the vehicle comprises selecting or modifying a desired control strategy from a plurality of possible control strategies. 
     
     
         6 . The method of  claim 5 , wherein the plurality of possible control strategies comprise sets of rules that relate to various driving contexts. 
     
     
         7 . The method of  claim 5 , wherein the plurality of possible control strategies comprises a default driving mode and a defensive driving mode, wherein the defensive driving mode comprises at least one of:
 controlling the speed of the vehicle so as to follow another vehicle at a predetermined safe distance;   turning-on lights; or   stopping the vehicle.   
     
     
         8 . The method of  claim 5 , wherein the plurality of possible control strategies comprise a continuum of driving modes or states based on a difference between the first image and the second image, wherein selecting or modifying the desired control strategy comprises selecting or modifying the desired control strategy so as to cause a smooth transition from a first set of driving rules to a second set of driving rules. 
     
     
         9 . The method of  claim 8 , wherein the smooth transition is configured so as to not be perceivable by a passenger in the vehicle. 
     
     
         10 . A method comprising:
 receiving, at a computing device, an image of a road from a camera coupled to a vehicle, wherein the vehicle is navigating a path proximate to the road;   based on a current location of the vehicle, obtaining a reference image from storage, wherein the reference image depicts one or more background objects associated with the road;   aligning the image relative to the reference image;   based on aligning the image relative to the reference image, performing a comparison between the image and the reference image;   based on the comparison, determining one or more foreground objects including at least one of a moving object, an obstacle or a road change; and   controlling the vehicle based on the one or more foreground objects.   
     
     
         11 . The method of  claim 10 , wherein the storage is positioned remotely from the vehicle. 
     
     
         12 . The method of  claim 10 , wherein controlling the vehicle based on the one or more foreground objects comprises at least one of: causing the vehicle to reduce speed, causing the vehicle to change lanes, causing the vehicle to change lanes, or causing the vehicle to follow another vehicle while keeping a predetermined safe distance. 
     
     
         13 . The method of  claim 10 , wherein controlling the vehicle based on the one or more foreground objects comprises selecting or modifying a desired control strategy from a plurality of possible control strategies. 
     
     
         14 . The method of  claim 10 , wherein the plurality of possible control strategies comprise sets of rules that relate to various driving contexts. 
     
     
         15 . The method of  claim 10 , wherein the plurality of possible control strategies comprises a default driving mode and a defensive driving mode, wherein the defensive driving mode comprises at least one of:
 controlling the speed of the vehicle so as to follow another vehicle at a predetermined safe distance;   turning-on lights; or   stopping the vehicle.   
     
     
         16 . The method of  claim 13 , wherein the plurality of possible control strategies comprise a continuum of driving modes or states based on the difference between the image and the reference image, wherein selecting or modifying the desired control strategy comprises selecting or modifying the desired control strategy so as to cause a smooth transition from a first set of driving rules to a second set of driving rules. 
     
     
         17 . The method of  claim 16 , wherein the smooth transition is configured so as to not be perceivable by a passenger in the vehicle. 
     
     
         18 . A method comprising:
 displaying on a user interface of a vehicle a plurality of images, wherein the plurality of images comprises a reference image depicting one or more background objects on a road or in a vicinity of the road, wherein the reference image is formed by identifying the one or more background objects based on common features in a plurality of source images, wherein the one or more background objects includes at least one of: a traffic sign, a building, or a lane marker;   capturing an image from a current location of the vehicle; and   determining, by a computing device of the vehicle, foreground objects wherein determining the foreground objects comprises subtracting from the image the one or more background objects depicted in the reference image, wherein the foreground objects comprise at least one of: a moving object, an obstacle, or a road change.   
     
     
         19 . The method of  claim 18 , wherein the reference image is stored remotely from the vehicle. 
     
     
         20 . The method of  claim 18 , wherein displaying the plurality of images comprises displaying an image of the vehicle relative to the one or more background objects on the user interface.