How to get image from custom server using service?

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Hello People,

I am trying to pass image from server to a client. The code complies when I use cv_bridge::toCvCopy, but it says core dumped when I actually call the image from the server. So I am currently trying to do the same thing using cv_bridge::toCvShare, but it throws following error -

error: no matching function for call to ‘toCvShare(robot_vision::request_imageResponse_<std::allocator<void> >::_img_type&, const char [5])’ cv::imshow("view", cv_bridge::toCvShare(srv.response.img, "bgr8")->image);

Inorder to check my server please check my previous question (I have updated the code with working one). My code for client is below -

#include <ros/ros.h>
#include <image_transport/image_transport.h>
#include <opencv2/highgui/highgui.hpp>
#include <cv_bridge/cv_bridge.h>
#include <sensor_msgs/image_encodings.h>
#include "sensor_msgs/Image.h"
#include <opencv2/imgproc/imgproc.hpp>
#include "robot_vision/request_image.h"
#include <cstdlib>
#include <iostream>

namespace enc = sensor_msgs::image_encodings;

cv_bridge::CvImagePtr cv_ptr;

int main(int argc,char **argv)
{
    ros::init(argc,argv,"image_client_node");
    ros::NodeHandle nh;
    ros::ServiceClient client = nh.serviceClient<robot_vision::request_image>("image_server");
    robot_vision::request_image srv;
    srv.request.request_msg = true;
    if(client.call(srv))
    {
        ROS_INFO("Service initiated");
        try
        {
           //cv_ptr = cv_bridge::toCvCopy(srv.response.img, sensor_msgs::image_encodings::BGR8);
           cv::imshow("view", cv_bridge::toCvShare(srv.response.img, "bgr8")->image);
           cv::waitKey(30);
        }
        catch (cv_bridge::Exception& e)
        {
           ROS_ERROR("cv_bridge exception: %s", e.what());
           //return;
        }
    }
    else
    {
        ROS_ERROR("Failed to call service image_server");
        return 1;
    }
    ros::spinOnce();
    return 0;
}