PythonTutorial2.py

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import libjevois as jevois
import cv2
import numpy as np
 
## Simple example of image processing using OpenCV in Python on JeVois
#
# This module is here for you to experiment with Python OpenCV on JeVois.
#
# By default, we get the next video frame from the camera as an OpenCV BGR (color) image named 'inimg'.
# We then apply some image processing to it to create an output BGR image named 'outimg'.
# We finally add some text drawings to outimg and send it to host over USB.
#
# @author Laurent Itti
# 
# @displayname Python Tutorial 2
# @videomapping YUYV 352 288 30.0 YUYV 352 288 30.0 JeVois PythonSandbox
# @email itti\@usc.edu
# @address University of Southern California, HNB-07A, 3641 Watt Way, Los Angeles, CA 90089-2520, USA
# @copyright Copyright (C) 2017 by Laurent Itti, iLab and the University of Southern California
# @mainurl http://jevois.org
# @supporturl http://jevois.org/doc
# @otherurl http://iLab.usc.edu
# @license GPL v3
# @distribution Unrestricted
# @restrictions None
# @ingroup modules
class PythonTutorial2:
    # ###################################################################################################
    ## Constructor
    def __init__(self):
        # Instantiate a JeVois Timer to measure our processing framerate:
        self.timer = jevois.Timer("sandbox", 100, jevois.LOG_INFO)
        
    # ###################################################################################################
    ## Process function with USB output
    def process(self, inframe, outframe):
        # Get the next camera image (may block until it is captured) and here convert it to OpenCV BGR by default. If
        # you need a grayscale image instead, just use getCvGRAY() instead of getCvBGR(). Also supported are getCvRGB()
        # and getCvRGBA():
        inimg = inframe.getCvBGR()
        
        # Start measuring image processing time (NOTE: does not account for input conversion time):
        self.timer.start()
 
        # Detect edges using the Laplacian algorithm from OpenCV:
        #
        # Replace the line below by your own code! See for example
        # - http://docs.opencv.org/trunk/d4/d13/tutorial_py_filtering.html
        # - http://docs.opencv.org/trunk/d9/d61/tutorial_py_morphological_ops.html
        # - http://docs.opencv.org/trunk/d5/d0f/tutorial_py_gradients.html
        # - http://docs.opencv.org/trunk/d7/d4d/tutorial_py_thresholding.html
        #
        # and so on. When they do "img = cv2.imread('name.jpg', 0)" in these tutorials, the last 0 means they want a
        # gray image, so you should use getCvGRAY() above in these cases. When they do not specify a final 0 in imread()
        # then usually they assume color and you should use getCvBGR() here.
        #
        # The simplest you could try is:
        #    outimg = inimg
        # which will make a simple copy of the input image to output.
        outimg = cv2.Laplacian(inimg, -1, ksize=5, scale=0.25, delta=127)
                
        # Write a title:
        cv2.putText(outimg, "JeVois Python Sandbox", (3, 20), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255,255,255),
                    1, cv2.LINE_AA)
        
        # Write frames/s info from our timer into the edge map (NOTE: does not account for output conversion time):
        fps = self.timer.stop()
        height, width, channels = outimg.shape # if outimg is grayscale, change to: height, width = outimg.shape
        cv2.putText(outimg, fps, (3, height - 6), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255,255,255), 1, cv2.LINE_AA)
 
        # Convert our BGR output image to video output format and send to host over USB. If your output image is not
        # BGR, you can use sendCvGRAY(), sendCvRGB(), or sendCvRGBA() as appropriate:
        outframe.sendCvBGR(outimg)