koyama's homework of 20150708

20150422/README-koyama-submit.md

@@ -0,0 +1,4 @@
+# homework20150422 Submission by KOYAMA
+
+Mirror node is a node which shows the mirror image of the image from the camera.
+If you launch "camera_mirror.launch", you will see two images-one from your camera, the other mirror of it.

20150422/launch/mirror_camera.launch

@@ -0,0 +1,15 @@
+<launch>
+  <arg name="show_debug_image" default="true" />
+
+  <include file="$(find homework20150422)/launch/camera.launch" />
+
+  <node name="camera_mirror" pkg="homework20150422" type="mirror.py">
+    <remap from="image" to="camera/image_raw"/>
+    <remap from="debug_image" to="camera/debug_image" />
+  </node>
+
+  <node name="debug_image_viewer" pkg="image_view" type="image_view"
+        if="$(arg show_debug_image)">
+    <remap from="image" to="camera/debug_image" />
+  </node>
+</launch>

20150422/scripts/face_detect_mono.py

@@ -18,13 +18,15 @@
 
 cascade_path = "/opt/ros/hydro/share/OpenCV/haarcascades/haarcascade_frontalface_alt2.xml"
 
+
+#define class
 class FaceDetectorMonoNode(object):
     """
 This class has feature to subscribe "image" and detect people face,
 then publishes those positions as geometry_msgs/Twist message.
 """
 
-    def __init__(self):
+    def __init__(self):#constructor
         # make instance of object for image processing
         try:
             self.bridge = CvBridge()
@@ -33,10 +35,14 @@ def __init__(self):
             rospy.logerr("Error: %s" % e)
 
         # 4. subscribe "image" topic whose message type is sensor_msgs/Image
-        self.image_subscriber = rospy.Subscriber("image", Image, self.image_callback)
+        # this node subscribes "image" topic which is of type Image, and if the message is subscribed image_callback will invoked. 
+        self.image_subscriber = rospy.Subscriber("image", Image, self.image_callback)#create subscriber object
+
 
         # declare publishers
-        self.face_pose_publisher = rospy.Publisher("twist", Twist)
+        # this node is publishing to the "twist" topic using message type Twist.
+        self.face_pose_publisher = rospy.Publisher("twist", Twist)# create publisher objct
+        # this node is publishing to the "debug_image" topic using message type Image.
         self.debug_image_publisher = rospy.Publisher("debug_image", Image)
 
     # 5. define callback function for image topic
@@ -89,11 +95,13 @@ def image_callback(self, msg):
         else:
             rospy.loginfo("no face detected.")
 
-if __name__ == '__main__':
+
+#main function
+if __name__ == '__main__':#他のプログラムで読み込む(importする)のでないとき、__name__='__main__'となる。つまり、実行されるとif=true
     # 3. At first, we must set node name, and register to the master.
     # In this case, node name is face_detector_mono
-    rospy.init_node("face_detector_mono")
-    face_detector = FaceDetectorMonoNode()
+    rospy.init_node("face_detector_mono")#set node of this program
+    face_detector = FaceDetectorMonoNode()#make instance of the class made above
 
     # wait for message comming
     rospy.spin()

20150422/scripts/mirror.py

@@ -0,0 +1,57 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+# Author: Ryo KOYAMA <[email protected]>
+
+# 1. import rospy to enable ROS feature of python
+import rospy
+
+# 2. import message files for python
+# cf. you can find what contains in a message by executing `rosmsg show <msg>`
+# e.g. rosmsg show sensor_msgs/Image
+from sensor_msgs.msg import Image # This imports sensor_msgs/Image
+from geometry_msgs.msg import Twist # This imports geometry_msgs/Twist
+
+# Tips: This is special utility for converting between ROS Image message and OpenCV Image format.
+from cv_bridge import CvBridge
+
+import cv2 # this imports opencv python interface
+
+class MIRROR(object):
+    """
+This class has feature to subscribe "image" and detect people face,
+then publishes those positions as geometry_msgs/Twist message.
+"""
+
+    def __init__(self):#constructor
+        # make instance of object for image processing
+        try:
+            self.bridge = CvBridge()
+        except Exception as e:
+            rospy.logerr("Error: %s" % e)
+
+        # 4. subscribe "image" topic whose message type is sensor_msgs/Image
+        self.image_subscriber = rospy.Subscriber("image", Image, self.image_callback)
+
+        # declare publishers
+        self.debug_image_publisher = rospy.Publisher("debug_image", Image)
+
+    # 5. define callback function for image topic
+    def image_callback(self, msg):
+        # 6. convert ROS sensor_msgs/Image to OpenCV format
+        img_mat = self.bridge.imgmsg_to_cv2(msg)
+
+        # 7. convert image to grey image
+        img_flip = cv2.flip(img_mat, 1)
+
+        # 12. publish debug image
+        pub_debug_img_msg = self.bridge.cv2_to_imgmsg(img_flip, encoding="bgr8")
+        self.debug_image_publisher.publish(pub_debug_img_msg)
+
+if __name__ == '__main__':
+    # 3. At first, we must set node name, and register to the master.
+    # In this case, node name is face_detector_mono
+    rospy.init_node("monokuro_camera")
+    mirror = MIRROR()
+
+    # wait for message comming
+    rospy.spin()