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Python OpenCV 3.3 NVIDIA Jetson TX example for built-in camera; L4T 28.1
#!/usr/bin/env python
# MIT License
# Copyright (c) 2017 Jetsonhacks
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import sys
import cv2
import numpy as np
def read_cam():
# On versions of L4T previous to L4T 28.1, flip-method=2
# Use the Jetson onboard camera
cap = cv2.VideoCapture("nvcamerasrc ! video/x-raw(memory:NVMM), width=(int)1280, height=(int)720,format=(string)I420, framerate=(fraction)30/1 ! nvvidconv flip-method=0 ! video/x-raw, format=(string)BGRx ! videoconvert ! video/x-raw, format=(string)BGR ! appsink")
if cap.isOpened():
windowName = "CannyDemo"
cv2.namedWindow(windowName, cv2.WINDOW_NORMAL)
cv2.resizeWindow(windowName,1280,720)
cv2.moveWindow(windowName,0,0)
cv2.setWindowTitle(windowName,"Canny Edge Detection")
showWindow=3 # Show all stages
showHelp = True
font = cv2.FONT_HERSHEY_PLAIN
helpText="'Esc' to Quit, '1' for Camera Feed, '2' for Canny Detection, '3' for All Stages. '4' to hide help"
edgeThreshold=40
showFullScreen = False
while True:
if cv2.getWindowProperty(windowName, 0) < 0: # Check to see if the user closed the window
# This will fail if the user closed the window; Nasties get printed to the console
break;
ret_val, frame = cap.read();
hsv=cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
blur=cv2.GaussianBlur(hsv,(7,7),1.5)
edges=cv2.Canny(blur,0,edgeThreshold)
if showWindow == 3: # Need to show the 4 stages
# Composite the 2x2 window
# Feed from the camera is RGB, the others gray
# To composite, convert gray images to color.
# All images must be of the same type to display in a window
frameRs=cv2.resize(frame, (640,360))
hsvRs=cv2.resize(hsv,(640,360))
vidBuf = np.concatenate((frameRs, cv2.cvtColor(hsvRs,cv2.COLOR_GRAY2BGR)), axis=1)
blurRs=cv2.resize(blur,(640,360))
edgesRs=cv2.resize(edges,(640,360))
vidBuf1 = np.concatenate( (cv2.cvtColor(blurRs,cv2.COLOR_GRAY2BGR),cv2.cvtColor(edgesRs,cv2.COLOR_GRAY2BGR)), axis=1)
vidBuf = np.concatenate( (vidBuf, vidBuf1), axis=0)
if showWindow==1: # Show Camera Frame
displayBuf = frame
elif showWindow == 2: # Show Canny Edge Detection
displayBuf = edges
elif showWindow == 3: # Show All Stages
displayBuf = vidBuf
if showHelp == True:
cv2.putText(displayBuf, helpText, (11,20), font, 1.0, (32,32,32), 4, cv2.LINE_AA)
cv2.putText(displayBuf, helpText, (10,20), font, 1.0, (240,240,240), 1, cv2.LINE_AA)
cv2.imshow(windowName,displayBuf)
key=cv2.waitKey(10)
if key == 27: # Check for ESC key
cv2.destroyAllWindows()
break ;
elif key==49: # 1 key, show frame
cv2.setWindowTitle(windowName,"Camera Feed")
showWindow=1
elif key==50: # 2 key, show Canny
cv2.setWindowTitle(windowName,"Canny Edge Detection")
showWindow=2
elif key==51: # 3 key, show Stages
cv2.setWindowTitle(windowName,"Camera, Gray scale, Gaussian Blur, Canny Edge Detection")
showWindow=3
elif key==52: # 4 key, toggle help
showHelp = not showHelp
elif key==44: # , lower canny edge threshold
edgeThreshold=max(0,edgeThreshold-1)
print 'Canny Edge Threshold Maximum: ',edgeThreshold
elif key==46: # , raise canny edge threshold
edgeThreshold=edgeThreshold+1
print 'Canny Edge Threshold Maximum: ', edgeThreshold
elif key==74: # Toggle fullscreen; This is the F3 key on this particular keyboard
# Toggle full screen mode
if showFullScreen == False :
cv2.setWindowProperty(windowName, cv2.WND_PROP_FULLSCREEN, cv2.WINDOW_FULLSCREEN)
else:
cv2.setWindowProperty(windowName, cv2.WND_PROP_FULLSCREEN, cv2.WINDOW_NORMAL)
showFullScreen = not showFullScreen
else:
print "camera open failed"
if __name__ == '__main__':
read_cam()
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