Extract header timestamp of Image message

edit

Is the extraction of a timestamp from the header of a sensor_msgs::Image that easy:

void imageCb(const sensor_msgs::ImageConstPtr& imsg) {
    cv_bridge::CvImagePtr cv_ptr;
    try {
        cv_ptr = cv_bridge::toCvCopy(imsg, sensor_msgs::image_encodings::TYPE_16UC1);
    }
    catch (cv_bridge::Exception& e) {
        ROS_ERROR("cv_bridge exception: %s", e.what());
        return;
    }

    //get header info
    std_msgs::Header h = imsg->header;
    cout<<h<<endl; //all at once
    cout<<h.stamp<<endl; //specific parts of it
    cout<<h.stamp.sec<<endl;
    cout<<h.stamp.nsec<<endl;
    cout<<h.seq<<endl;

    //do some with it

This is the output

seq: 11536  //all info
stamp: 1455792836.004090186
frame_id: camera_depth_optical_frame

1455792836.004090186 //stamp
1455792836 //sec
4090186 //nsec
11536 //seq