1. An image processing method comprising: receiving, from a camera, a camera captured image comprising a user drawn image, at least part of the user drawn image being within a field of view of the camera; applying an image processing operation to the camera captured image so as to generate an image feature within the camera captured image which corresponds to the user drawn image; thinning the image feature to a line width which is smaller than a line width associated with the image feature so as to generate a modified width image feature; and generating vector data from pixels associated with the modified width image feature so that the vector data substantially represents the modified width image feature; wherein the image processing operation comprises: carrying out a flood fill operation on the camera captured image so as to detect boundary pixels associated with a boundary between a first image region corresponding to the user drawn image and a second image region corresponding to a flood filled image area; and for each boundary pixel, associating a predetermined number of pixels surrounding the boundary pixel with that boundary pixel, in which the image feature comprises the boundary pixels together with the pixels associated with those boundary pixels.