Using CameraServer
Grabbing Frames from CameraServer
The WPILibPi image comes with all the necessary libraries to make your own vision processing system. In order to get the current frame from the camera, you can use the CameraServer library. For information about CameraServer, the Read and Process Video: CameraServer Class.
from cscore import CameraServer
import cv2
import numpy as np
CameraServer.enableLogging()
camera = CameraServer.startAutomaticCapture()
camera.setResolution(width, height)
sink = cs.getVideo()
while True:
time, input_img = cvSink.grabFrame(input_img)
if time == 0: # There is an error
continue
הערה
OpenCV reads in the image as BGR, not RGB for historical reasons. Use cv2.cvtColor
if you want to change it to RGB.
Below is an example of an image that might be grabbed from CameraServer.
Sending frames to CameraServer
Sometimes, you may want to send processed video frames back to the CameraServer instance for debugging purposes, or viewing in a dashboard application like Shuffleboard.
#
# CameraServer initialization code here
#
output = cs.putVideo("Name", width, height)
while True:
time, input_img = cvSink.grabFrame(input_img)
if time == 0: # There is an error
output.notifyError(sink.getError())
continue
#
# Insert processing code here
#
output.putFrame(processed_img)
As an example, the processing code could outline the target in red, and show the corners in yellow for debugging purposes.
Below is an example of a fully processed image that would be sent back to CameraServer and displayed on the Driver Station computer.