1. A method for training a neural network of a visual recognition computer system, the method comprising the steps of: extracting at least one feature of an image or video frame; approximating the at least one feature of the image or video frame with the neural network; measuring a feature difference between the extracted at least one feature of the image or video frame and the approximated at least one feature of the image or video frame; and adjusting at least one parameter of the neural network to minimize the measured feature difference.