function resetContext() {
      if(isContextReplaced) {
        curContext = originalContext;
        isContextReplaced = false;

        p.updatePixels();
      }
    }
This function takes content from a canvas and turns it into an ImageData object to be used with a PImage

@returns {ImageData}        ImageData object to attach to a PImage (1D array of pixel data)

@see PImage