Change frame_id and timestamp of topics

repairTimeStamps.py

#!/usr/bin/env python

import rospy
import sys
from std_msgs.msg import String, Header
from sensor_msgs.msg import CameraInfo
from sensor_msgs.msg import Image

class publishTF(object):

	def __init__(self):
		rospy.loginfo("Initialising subscriber and publisher")
		self.left_image_raw_sub=rospy.Subscriber('/zed/left/image_raw',Image, self.callback_left_image_raw, queue_size=1)
		self.right_image_raw_sub=rospy.Subscriber('/zed/right/image_raw',Image, self.callback_right_image_raw, queue_size=1)
		self.left_info_sub=rospy.Subscriber('/zed/left/camera_info',CameraInfo, self.callback_left_info, queue_size=1)
		self.right_info_sub=rospy.Subscriber('/zed/right/camera_info',CameraInfo, self.callback_right_info, queue_size=1)

		# self.lastMsg1=None
		# self.lastMsg2=None
		# self.lastMsg3=None
		# self.lastMsg4=None
# self.i=rospy.Publisher('/imu_new', Imu, queue_size=1)
		self.left_image_raw_pub=rospy.Publisher('/zed/left/image_raw_currentStamp',Image, queue_size=1)
		self.right_image_raw_pub=rospy.Publisher('/zed/right/image_raw_currentStamp',Image, queue_size=1)
		self.left_info_pub=rospy.Publisher('/zed/left/camera_info_currentStamp',CameraInfo, queue_size=1)
		self.right_info_pub=rospy.Publisher('/zed/right/camera_info_currentStamp',CameraInfo, queue_size=1)
		rospy.sleep(2)
		rospy.loginfo("initialised")

	def callback_left_image_raw(self, data):
		# self.left_image_raw_pub=data
		data.header.stamp=rospy.Time.now()
		data.header.frame_id='zed_frame'
		self.left_image_raw_pub.publish(data)
		# imumsg.header.stamp = rospy.Time.now()
	def callback_right_image_raw(self, data):
		# self.right_image_raw_pub=data
		data.header.stamp=rospy.Time.now()
		data.header.frame_id='zed_frame'
		self.right_image_raw_pub.publish(data)
	def callback_left_info(self, data):
		# self.left_info_raw_pub=data
		data.header.frame_id='zed_frame'
		data.header.stamp=rospy.Time.now()
		self.left_info_pub.publish(data)
	def callback_right_info(self, data):
		# self.right_info_raw_pub=data
		data.header.frame_id='zed_frame'
		data.header.stamp=rospy.Time.now()
		self.right_info_pub.publish(data)
	# def do_work(self):
	# 	self.splitStrings= str(self.lastMsg).split(",")
	# 	imumsg= Imu()
	# 	imumsg.header.stamp = rospy.Time.now()
	# 	imumsg.header.frame_id='imu'
	# 	imumsg.orientation.x=float(self.splitStrings[1][2:])
	# 	imumsg.orientation.y=float(self.splitStrings[2][2:])
	# 	imumsg.orientation.z=float(self.splitStrings[3][2:])
	# 	imumsg.orientation.w=float(self.splitStrings[4][2:])
	# 	rospy.loginfo(self.splitStrings[1])
	# 	self.imu_pub.publish(imumsg)

	# def run(self):
	# 	r=rospy.Rate(1)
	# 	while not rospy.is_shutdown():
	# 		# self.do_work()
	# 		r.sleep()

if __name__=='__main__':
	rospy.init_node('publish_tf')
	obj=publishTF()
	while not rospy.is_shutdown():
		rospy.spin()

Subscribes to four topics (see topics in Subscriber nodes)
Publishes to four topics (see topics in Publisher nodes)
Changes time stamp to node and frame_id to 'zed_frame' each time a callback occurs (ie message arrives on that topic)