Two Topics with Same Callback

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Hi everyone,

I am subscribing to two different topics (each with different md5sums) using a single callback. I am using the message_filters class to achieve this. In my broadcaster, I am publishing a point cloud and an opencv image. I want to subscribe in a separate code. My callback signature looks like so:

 void callback(const sensor_msgs::ImageConstPtr& ensensoImage, const sensor_msgs::PointCloud2ConstPtr& ensensoCloud)
{
   cv::Mat ir; 
   PointCloudT cloud;
   getImage(ensensoImage, ir);
   getCloud(ensensoCloud, cloud);
   ROS_INFO_STREAM("cloud: " << cloud);

   std::lock_guard<std::mutex> lock(mutex);
   this->ir = ir;
   this->cloud = cloud;
   updateImage = true;
   updateCloud = true;

}

When I run my code, however, I get an std::terminate as follows:

user@user:~/catkin_ws$ rosrun ensenso ensenso_viewer terminate called after throwing an instance of 'ros::ConflictingSubscriptionException' what(): Tried to subscribe to a topic with the same name but different md5sum as a topic that was already subscribed [sensor_msgs/PointCloud2/1158d486dd51d683ce2f1be655c3c181 vs. sensor_msgs/Image/060021388200f6f0f447d0fcd9c64743] Aborted (core dumped)

Is it not possible to have a callback with different classes of a namespace or am I missing something?

For reference, the whole code is here.

I would appreciate any help. Thanks!