Selection of Benign files is not uniform. Only first 64 files are being used.

[cssanchit]

 # generate batch of benign
idb = np.random.randint(0, xmal_batch.shape[0], batch_size)

should be

 # generate batch of benign
idb = np.random.randint(0, x_train_ben.shape[0], batch_size)

I may be wrong, Please clarify. Thanks