Size of single pixel in world units.

Hello,

I am having stereo camera parameters i.e intrinsic as well as extrinsic matrices. Using stereo camera, I took picture of red color and got the X,Y and Z values of this in world unit. Now I want to find out the size of single pixel in world unit. How to do that?

Thanks.

[Walter Roberson]

When you are using stereo, size of any given pixel depends where in the field of view it is and depends upon content of the image (pixels corresponding to closer objects represent a smaller area per-pixel than pixels corresponding to further objects.)

[Naseeb Gill]

Sir, actually what I want to get is area of a irregular red surface. I have X,Y and Z values of red surface. From this, I can get the X, Y and Z values of its perimeter. So, using these values, how I can get the surface area? I want to know that. For that only, I tried to find the area of each pixel. Can you help me to find out the surface area? Some X and Y values are negative also becuase of left camera position. So, when I used delaunay function, it shows error. I asked similar question here but didn't get the correct asnwer.