ROS Image Subscriber / JPEG Saver

ros_image_saver.py

#! /usr/bin/python
# Copyright (c) 2015, Rethink Robotics, Inc.

# Using this CvBridge Tutorial for converting
# ROS images to OpenCV2 images
# http://wiki.ros.org/cv_bridge/Tutorials/ConvertingBetweenROSImagesAndOpenCVImagesPython

# Using this OpenCV2 tutorial for saving Images:
# http://opencv-python-tutroals.readthedocs.org/en/latest/py_tutorials/py_gui/py_image_display/py_image_display.html

# rospy for the subscriber
import rospy
# ROS Image message
from sensor_msgs.msg import Image
# ROS Image message -> OpenCV2 image converter
from cv_bridge import CvBridge, CvBridgeError
# OpenCV2 for saving an image
import cv2

# Instantiate CvBridge
bridge = CvBridge()

def image_callback(msg):
    print("Received an image!")
    try:
        # Convert your ROS Image message to OpenCV2
        cv2_img = bridge.imgmsg_to_cv2(msg, "bgr8")
    except CvBridgeError, e:
        print(e)
    else:
        # Save your OpenCV2 image as a jpeg 
        cv2.imwrite('camera_image.jpeg', cv2_img)

def main():
    rospy.init_node('image_listener')
    # Define your image topic
    image_topic = "/cameras/left_hand_camera/image"
    # Set up your subscriber and define its callback
    rospy.Subscriber(image_topic, Image, image_callback)
    # Spin until ctrl + c
    rospy.spin()

if __name__ == '__main__':
    main()

Hello, I am working on a project having a realsense camera in a gazebo robot model and would like to manipulate it with rospy or roscpp. (The camera should identify the color in the gazebo environment ). Thanks

Hello, I'm sorry, I'm still new using ROS. I wanted to ask where does the file saved?

Hi, Is there a way to republish converted jpeg to a certain topic? Using this program as a real-time converter? Thanks.

should be, you could publish the saved image

Hello, I'm sorry, I'm still new using ROS. I wanted to ask where does the file saved?

Image location in your "Catkin_make" folder that you uing "Catkin_make" command

I need to play back the rosbag at a slower speed to capture all the frames, or some of them will be lost. Is there a more elegant solution?

I need to play back the rosbag at a slower speed to capture all the frames, or some of them will be lost. Is there a more elegant solution?

I think on the ros Wiki, there a Parameter where you can adjust the playback speed.