How do I find the area of the image in meters using MATLAB?

Hi,

I am trying to estimate the area of a rooftop of a building for some data analysis. I have obtained the image of the rooftop of the building using google maps and doing some image analysis, at the same time I need to evaluate the area of the building's rooftop as well. How can I do this using Matlab?

Thanks

[gonzalo Mier]

This is not a Matlab problem, it's a mathematic one. You need to know some reference to measure the dimensions of the rooftop. Then you can just do height*weigth to find the area.

[darova]

+1

Answer 1

[Michael Hawks]

I agree with gonzalo -- it's not really a Matlab question. But if you know anything about your camera you could also solve it that way without needing to find a reference object in the image.

Each pixel will see are area on the ground that is x = ( pixel size * range / focal length ) across. If you're looking straight down (as for Google Earth), the horizontal and vertical distance will be the same. For oblique views, the vertical dimension will increase by (1/cos theta).