# Converting Pixel Coordinates to spatial coordinates: Python, Ros

Hi,

So currently, i am reading an image from my robot's camera, located on its hand. I want to obtain the set of coordinates of a certain object, from both the camera's perspective and the robot's base perspective, given a certain pixel coordinate from the camera i.e. 340x200 (location of my object on the camera image)

I have been using the equation on the second line from this link

But i haven't obtained any good results.(I have inverted the equation,, since i want a set of 3d coordinates from a pair of pixel coordinates and not the opposite as the original equation would give)

So because i didnt get any good result, i tried breaking down the equation. The matrix [R|T] converts the [x,y,z,1] coordinates to the base frame right?? (assuming [R|T] is with respect to the base frame)

So if I wanted the coordinate WRT to the camera's frame, could I just use the equation, without the [R|T] matrix? i.e [u,v,1] = A[X,Y,Z]?

If not, how should i proceed to convert the pixel coordinates to spatial coordinates