Package org.wpilib.vision.process

package org.wpilib.vision.process

Classes in the org.wpilib.vision.process package are designed to simplify using OpenCV vision processing code from a robot program.

An example use case for grabbing a yellow tote from 2015 in autonomous:

public class Robot extends TimedRobot
    implements VisionRunner.Listener<MyFindTotePipeline> {

     // A USB camera connected to the roboRIO.
     private VideoSource usbCamera;

     // A vision pipeline. This could be handwritten or generated by GRIP.
     // This has to implement VisionPipeline.
     // For this example, assume that it's perfect and will always see the tote.
     private MyFindTotePipeline findTotePipeline;
     private VisionThread findToteThread;

     // The object to synchronize on to make sure the vision thread doesn't
     // write to variables the main thread is using.
     private final Object visionLock = new Object();

     // The pipeline outputs we want
     private boolean pipelineRan = false; // lets us know when the pipeline has actually run
     private double angleToTote = 0;
     private double distanceToTote = 0;

     public Robot() {
         usbCamera = CameraServer.startAutomaticCapture(0);
         findTotePipeline = new MyFindTotePipeline();
         findToteThread = new VisionThread(usbCamera, findTotePipeline, this);
     }

    @Override
     public void copyPipelineOutputs(MyFindTotePipeline pipeline) {
         synchronized (visionLock) {
             // Take a snapshot of the pipeline's output because
             // it may have changed the next time this method is called!
             this.pipelineRan = true;
             this.angleToTote = pipeline.getAngleToTote();
             this.distanceToTote = pipeline.getDistanceToTote();
         }
     }

    @Override
     public void autonomousInit() {
         findToteThread.start();
     }

    @Override
     public void autonomousPeriodic() {
         double angle;
         double distance;
         synchronized (visionLock) {
             if (!pipelineRan) {
                 // Wait until the pipeline has run
                 return;
             }
             // Copy the outputs to make sure they're all from the same run
             angle = this.angleToTote;
             distance = this.distanceToTote;
         }
         if (!aimedAtTote()) {
             turnToAngle(angle);
         } else if (!droveToTote()) {
             driveDistance(distance);
         } else if (!grabbedTote()) {
             grabTote();
         } else {
             // Tote was grabbed and we're done!
             return;
         }
     }

}

Class	Description
VisionPipeline	A vision pipeline is responsible for running a group of OpenCV algorithms to extract data from an image.
VisionRunner<P extends VisionPipeline>	A vision runner is a convenient wrapper object to make it easy to run vision pipelines from robot code.
VisionRunner.Listener<P extends VisionPipeline>	Listener interface for a callback that should run after a pipeline has processed its input.
VisionThread	A vision thread is a special thread that runs a vision pipeline.