The Coordinate Transformation Problem in ROS

How can I convert 2D image coordinates to 3D world coordinates in ros-noetic with C++ and the zed-ros-wrapper. I get the 2D image coordinates (u,v)with deep learning algorithm, how to get 3D world coordinates in ros-noetic ?
Z = depth value of the pixel (u,v) from the depth map
X = (( u - c_x) * Z) / (f_x)
Y = (( v - c_y) * Z) / (f_y)
how can I get the z c_x c_y f_x and f_y in zed-ros-wrapper ?thank you very much!

void depthCallback(const sensor_msgs::Image::ConstPtr& msg)
{
// Get a pointer to the depth values casting the data
// pointer to floating point
float* depths = (float*)(&msg->data[0]);
………………………………………………

Is the distance information obtained in these functions statements the value of Z(Z = depth value of the pixel (u,v) from the depth map)?

Hi @zhangYQHBAU

this information is available in the camera_info topics.

Yes, it is

it’s exactly what I need.

Thank you my Myzhar.