random rotate of images is not really random
in bob.learn.tensorflow/bob/learn/tensorflow/dataset/__init__.py
there is:
if random_rotate:
image = tf.contrib.image.rotate(
image,
angles=numpy.random.randint(-5, 5),
interpolation="BILINEAR")
this random number (from numpy) is going to be evaluated once and then all images will be rotated using that angle.