I have a depth image topic that is visualized perfectly in rviz, both as image and as depth cloud. I created a node for subscribing to said topic and then just republish all the messages. The new topic can be visualized as a depth image in rviz, but no points are visible when I select "depth cloud". I compared the depth images from the two topics, and they look the same.

However, it looks like the republished topic lacks information. Under "status", the republished depth cloud does not have the field "Depth Image Size", as well as it lacks a color transformer. See the image below:

Here the depth cloud from the original topic is shown

Ultimately I am going to use OpenCV to change the depth image, but first I just want to see the republished depth could visualized in rviz.

I followed the image_transport tutorial and created this code:

#include <ros/ros.h>
#include <image_transport/image_transport.h>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <cv_bridge/cv_bridge.h>
#include <ros/console.h>

image_transport::Publisher pub;

void imageCallback(const sensor_msgs::ImageConstPtr& msg)
{
    pub.publish(msg);
}

int main(int argc, char **argv)
{
    ros::init(argc, argv, "image_listener");
    ros::NodeHandle nh;

    image_transport::ImageTransport it(nh);

    pub = it.advertise("hacked/image_raw", 1);

    image_transport::Subscriber sub = it.subscribe("camera/depth/image_raw", 1, imageCallback);

    ros::spin();
} 

Hope you have an idea about what might be wrong :)