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You might want to convert the sensor_msgs/Image datatype to an OpenCV image. The cv_bridge tutorial for Python shows how to do so: http://www.ros.org/wiki/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython

You might want to convert the sensor_msgs/Image datatype to an OpenCV image. The cv_bridge tutorial for Python shows how to do so: http://www.ros.org/wiki/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython

OpenCV then has a function "imshow" which would allow you to display the image.

You might want to convert the sensor_msgs/Image datatype to an OpenCV image. The cv_bridge tutorial for Python shows how to do so: http://www.ros.org/wiki/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython

Our group has also has some sample code in SVN: http://code.google.com/p/albany-ros-pkg/source/browse/branches/seminar2011/ex_vision/src/capture.py which shows how to capture an image, and display it using OpenCV then has a function "imshow" which would allow you to display the image. and cv_bridge.

You might want to convert the sensor_msgs/Image datatype to an OpenCV image. The cv_bridge tutorial for Python shows how to do so: http://www.ros.org/wiki/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython

Our group has also has some sample The below code in SVN: http://code.google.com/p/albany-ros-pkg/source/browse/branches/seminar2011/ex_vision/src/capture.py which shows how to capture is an example from our SVN ( http://code.google.com/p/albany-ros-pkg ) that captures an image, blurs it, and displays it:

!/usr/bin/env python

""" Example code of how to convert ROS images to OpenCV's cv::Mat This is the solution to HW2, using Python.

See also cv_bridge tutorials: http://www.ros.org/wiki/cv_bridge """

import roslib; roslib.load_manifest('ex_vision') import rospy

import cv from cv_bridge import CvBridge, CvBridgeError

from std_msgs.msg import String from sensor_msgs.msg import Image

class image_blur:

def __init__(self): # initialize a node called hw2 rospy.init_node("hw2")

# create a window to display it results in
cv.NamedWindow("image_view", 1)

# part 2.1 of hw2 -- subscribe to a topic called image
self.image_sub = rospy.Subscriber("image", Image, self.callback)

def callback(self,data): """ This is a callback which recieves images and processes them. """ # convert image into openCV format bridge = CvBridge() try: # bgr8 is the pixel encoding -- 8 bits per color, organized as blue/green/red cv_image = bridge.imgmsg_to_cv(data, "bgr8") except CvBridgeError, e: # all print statements should use a rospy.log_ form, don't print! rospy.loginfo("Conversion failed")

# we could do anything we want with the image here
# for now, we'll blur using OpenCV and cv_bridge. 

a median blur cv.Smooth(cv_image, cv_image, smoothtype=cv.CV_MEDIAN, param1=31, param2=0, param3=0, param4=0) # show the image cv.ShowImage("image_view", cv_image) cv.WaitKey(3)

if __name__ == '__main__': image_blur() try:
rospy.spin() except KeyboardInterrupt: print "Shutting down" cv.DestroyAllWindows()

You might want to convert the sensor_msgs/Image datatype to an OpenCV image. The cv_bridge tutorial for Python shows how to do so: http://www.ros.org/wiki/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython

The below code is an example from our SVN ( http://code.google.com/p/albany-ros-pkg ) that captures an image, blurs it, and displays it:

!/usr/bin/env python

#!/usr/bin/env python
""" 
  Example code of how to convert ROS images to OpenCV's cv::Mat
  This is the solution to HW2, using Python.

Python. See also cv_bridge tutorials: http://www.ros.org/wiki/cv_bridge """

""" import roslib; roslib.load_manifest('ex_vision') import rospy

rospy import cv from cv_bridge import CvBridge, CvBridgeError

CvBridgeError from std_msgs.msg import String from sensor_msgs.msg import Image

Image class image_blur:

image_blur: def __init__(self): # initialize a node called hw2 rospy.init_node("hw2")

rospy.init_node("hw2")

    # create a window to display results in
 cv.NamedWindow("image_view", 1)

 # part 2.1 of hw2 -- subscribe to a topic called image
 self.image_sub = rospy.Subscriber("image", Image, self.callback)

def callback(self,data): """ This is a callback which recieves images and processes them. """ # convert image into openCV format bridge = CvBridge() try: # bgr8 is the pixel encoding -- 8 bits per color, organized as blue/green/red cv_image = bridge.imgmsg_to_cv(data, "bgr8") except CvBridgeError, e: # all print statements should use a rospy.log_ form, don't print! rospy.loginfo("Conversion failed")

failed")

    # we could do anything we want with the image here
 # for now, we'll blur using a median blur
 cv.Smooth(cv_image, cv_image, smoothtype=cv.CV_MEDIAN, param1=31, param2=0, param3=0, param4=0)

 # show the image
 cv.ShowImage("image_view", cv_image)
 cv.WaitKey(3)

if __name__ == '__main__': image_blur() try:
rospy.spin() except KeyboardInterrupt: print "Shutting down" cv.DestroyAllWindows()

cv.DestroyAllWindows()