#include <cv_bridge/cv_bridge.h>
const stereo_msgs::DisparityImageConstPtr& msg; // We got this from a subscription callback.
cv::Mat output_image;
cv_bridge::CvImageConstPtr cv_img_ptr = cv_bridge::toCvShare(msg->image, msg);
// This is a shallow copy.
output_image = cv_img_ptr->image;
cv_bridge::CvImage image_cv_bridge;
image_cv_bridge.header.frame_id = "map";
image_cv_bridge.image = output_image;
publisher_.publish(image_cv_bridge.toImageMsg());
Please use the package in the repo. This also wraps some of the Eigen/TF conversions for common datatypes (Eigen::Quaterniond, Eigen::Vector3d), so it is a viable alternative to {tf,eigen}_conversions in most cases. It also transforms minkindr Transformations back and forth to both messages and TF.
Please use . This allows very easy conversions to/from ROS messages.