How to color correct an image that I have projected on a plane with the alpha channel

Hello.

what’s the proper way to add a color correction to a plane where I have applied an alpha image like the one you see below ?

I would like to correct the color of the clothes of the man,because the color of the pants is the same of the color of the floor and the color of the jacket is the same as the color of the door / window and it’s not good for what I want to achieve. Below you can see that I have applied a basic color correction,but its wrong because it corrects everything,but I want that only the clothes of the man is corrected. what’s the method here ?

as u can see below,I have removed the texture of the house from the rendering view and the only images left are the alpha images of the men,that I want to correct. BUT the color balance is able to correct the illumination of the whole alpha plane,not only of the clothes. its not good.