Loading external digit images for pylearn2 convnet example

pylearn2_convnet_loader.py

import cv2, numpy as np
import theano
from pylearn2.utils import serial

def load_pl2_recognizer(model_path):
    model = serial.load(model_path)

    X = model.get_input_space().make_theano_batch()
    Y = model.fprop(X)

    recognize = theano.function([X], Y)
    return recognize

pl2recognizer = load_pl2_recognizer('C:\\model.pkl')

def recognize_digit(digit, probabilities=False):
    # Assuming 28x28 uint8 white digit with black background
    digit = cv2.normalize(digit, alpha=0.0, beta=1.0, norm_type=cv2.cv.CV_MINMAX, dtype=cv2.cv.CV_64F)
    digit = digit.reshape(-1, 28, 28, 1)
    ans = pl2recognizer(digit)
    if not probabilities:
        ans = np.argmax(ans, axis=1)
    return ans