How to calculate Noise and distortion of an image? I need to make an application in iphone which needs to calculate noise, geometric deformation other distortions in an image. How to do this? I have done some image processing stuff with opencv + iphone. But I dont know how to calculate these parameters.

1) How to calculate noise in an image?

2) What is geometric deformation and how to calculate geometric deformation of an image?

3) Is geometric deformation and distortion are same parameters in terms of image filter? or any other distortions available to calculate an image is good quality or not?
You should do it on a known set of calibration targets. For example, this type of calibration target is being used to measure noise. You should find the patches locations, and measure the noise by some metric. If you don't know any metric, you can start by browsing DXOlabs site, or Imatest site.

I guess that you mean radial distortion. Radial distortion can be found by a process called camera calibration, by using a known target such as checkerboard. For more info, see Camera Calibration Toolbox. Here is an image from another software that does it:

I didn't understand your question at all. Please reprase it and add more information.