Use C# MVC to remove background from an image

I have images of different sizes and different image formats (mostly .jpg and .png) that I need the background stripped off. The new image can be png, jpg, gif, or whatever. I have a feeling you will have to use EMGU CV background subtraction methods to get the job done. The last developer I had try, who was very skilled, couldn't get it working 100% right and he wasnt using any CV. But EMGU CV is not a requirement. Upon acceptance of the project I will send you a solution file that you will place your code into. It is a simple c# MVC application with a submit form that submits an image file back to a controller. Your code would start once the image file is sent to the controller and I would need it returned back to me by the time I need to present the View() back to the user. I will upload some sample images. I am expecting the new background to be pure white, or whatever color I chose really.