svhn.py

# Copyright 2015 Matthieu Courbariaux

# This file is part of BinaryConnect.

# BinaryConnect is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# BinaryConnect is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with BinaryConnect.  If not, see <http://www.gnu.org/licenses/>.

from __future__ import print_function

import sys
import os
import time

import numpy as np
np.random.seed(1234) # for reproducibility?

# specifying the gpu to use
# import theano.sandbox.cuda
# theano.sandbox.cuda.use('gpu1') 
import theano
import theano.tensor as T

import lasagne

import cPickle as pickle
import gzip

import batch_norm
import binary_connect
   
from pylearn2.datasets.svhn import SVHN
from pylearn2.utils import serial

from collections import OrderedDict

if __name__ == "__main__":
    
    # Batch Normalization parameters
    batch_size = 50
    print("batch_size = "+str(batch_size))
    # alpha is the exponential moving average factor
    alpha = .1
    print("alpha = "+str(alpha))
    epsilon = 1e-4
    print("epsilon = "+str(epsilon))
    
    # Training parameters
    num_epochs = 200
    print("num_epochs = "+str(num_epochs))
    
    # BinaryConnect    
    binary = True
    print("binary = "+str(binary))
    stochastic = True
    print("stochastic = "+str(stochastic))
    # (-H,+H) are the two binary values
    # H = "Glorot"
    H = 1.
    print("H = "+str(H))
    # W_LR_scale = 1.    
    W_LR_scale = "Glorot" # "Glorot" means we are using the coefficients from Glorot's paper
    print("W_LR_scale = "+str(W_LR_scale))
    
    # Decaying LR 
    LR_start = 0.01
    print("LR_start = "+str(LR_start))
    LR_fin = 0.000003
    print("LR_fin = "+str(LR_fin))
    LR_decay = (LR_fin/LR_start)**(1./num_epochs)
    print("LR_decay = "+str(LR_decay))
    # BTW, LR decay might good for the BN moving average...
    
    print('Loading SVHN dataset')
    
    train_set = SVHN(
            which_set= 'splitted_train',
            path= "${SVHN_LOCAL_PATH}",
            axes= ['b', 'c', 0, 1])
     
    valid_set = SVHN(
        which_set= 'valid',
        path= "${SVHN_LOCAL_PATH}",
        axes= ['b', 'c', 0, 1])
    
    test_set = SVHN(
        which_set= 'test',
        path= "${SVHN_LOCAL_PATH}",
        axes= ['b', 'c', 0, 1])
    
    # bc01 format
    # print train_set.X.shape
    train_set.X = np.reshape(train_set.X,(-1,3,32,32))
    valid_set.X = np.reshape(valid_set.X,(-1,3,32,32))
    test_set.X = np.reshape(test_set.X,(-1,3,32,32))
    
    # for hinge loss (targets are already onehot)
    train_set.y = np.subtract(np.multiply(2,train_set.y),1.)
    valid_set.y = np.subtract(np.multiply(2,valid_set.y),1.)
    test_set.y = np.subtract(np.multiply(2,test_set.y),1.)

    print('Building the CNN...') 
    
    # Prepare Theano variables for inputs and targets
    input = T.tensor4('inputs')
    target = T.matrix('targets')
    LR = T.scalar('LR', dtype=theano.config.floatX)

    cnn = lasagne.layers.InputLayer(
            shape=(None, 3, 32, 32),
            input_var=input)
    
    # 64C3-64C3-P2             
    cnn = binary_connect.Conv2DLayer(
            cnn, 
            binary=binary,
            stochastic=stochastic,
            H=H,
            W_LR_scale=W_LR_scale,
            num_filters=64, 
            filter_size=(3, 3),
            pad=1,
            nonlinearity=lasagne.nonlinearities.identity)
    
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify) 
            
    cnn = binary_connect.Conv2DLayer(
            cnn, 
            binary=binary,
            stochastic=stochastic,
            H=H,
            W_LR_scale=W_LR_scale,
            num_filters=64, 
            filter_size=(3, 3),
            pad=1,
            nonlinearity=lasagne.nonlinearities.identity)
    
    cnn = lasagne.layers.MaxPool2DLayer(cnn, pool_size=(2, 2))
    
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
            
    # 128C3-128C3-P2             
    cnn = binary_connect.Conv2DLayer(
            cnn, 
            binary=binary,
            stochastic=stochastic,
            H=H,
            W_LR_scale=W_LR_scale,
            num_filters=128, 
            filter_size=(3, 3),
            pad=1,
            nonlinearity=lasagne.nonlinearities.identity)
    
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
            
    cnn = binary_connect.Conv2DLayer(
            cnn, 
            binary=binary,
            stochastic=stochastic,
            H=H,
            W_LR_scale=W_LR_scale,
            num_filters=128, 
            filter_size=(3, 3),
            pad=1,
            nonlinearity=lasagne.nonlinearities.identity)
    
    cnn = lasagne.layers.MaxPool2DLayer(cnn, pool_size=(2, 2))
    
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
            
    # 256C3-256C3-P2              
    cnn = binary_connect.Conv2DLayer(
            cnn, 
            binary=binary,
            stochastic=stochastic,
            H=H,
            W_LR_scale=W_LR_scale,
            num_filters=256, 
            filter_size=(3, 3),
            pad=1,
            nonlinearity=lasagne.nonlinearities.identity)
    
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
                  
    cnn = binary_connect.Conv2DLayer(
            cnn, 
            binary=binary,
            stochastic=stochastic,
            H=H,
            W_LR_scale=W_LR_scale,
            num_filters=256, 
            filter_size=(3, 3),
            pad=1,
            nonlinearity=lasagne.nonlinearities.identity)
    
    cnn = lasagne.layers.MaxPool2DLayer(cnn, pool_size=(2, 2))
    
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
    
    # print(cnn.output_shape)
    
    # 1024FP-1024FP-10FP            
    cnn = binary_connect.DenseLayer(
                cnn, 
                binary=binary,
                stochastic=stochastic,
                H=H,
                W_LR_scale=W_LR_scale,
                nonlinearity=lasagne.nonlinearities.identity,
                num_units=1024)      
                  
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
            
    cnn = binary_connect.DenseLayer(
                cnn, 
                binary=binary,
                stochastic=stochastic,
                H=H,
                W_LR_scale=W_LR_scale,
                nonlinearity=lasagne.nonlinearities.identity,
                num_units=1024)      
                  
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.rectify)
    
    cnn = binary_connect.DenseLayer(
                cnn, 
                binary=binary,
                stochastic=stochastic,
                H=H,
                W_LR_scale=W_LR_scale,
                nonlinearity=lasagne.nonlinearities.identity,
                num_units=10)      
                  
    cnn = batch_norm.BatchNormLayer(
            cnn,
            epsilon=epsilon, 
            alpha=alpha,
            nonlinearity=lasagne.nonlinearities.identity)

    train_output = lasagne.layers.get_output(cnn, deterministic=False)
    
    # squared hinge loss 
    loss = T.mean(T.sqr(T.maximum(0.,1.-target*train_output)))
    
    if binary:
        
        # W updates
        W = lasagne.layers.get_all_params(cnn, binary=True)
        W_grads = binary_connect.compute_grads(loss,cnn)
        updates = lasagne.updates.adam(loss_or_grads=W_grads, params=W, learning_rate=LR)
        updates = binary_connect.clipping_scaling(updates,cnn)
        
        # other parameters updates
        params = lasagne.layers.get_all_params(cnn, trainable=True, binary=False)
        updates = OrderedDict(updates.items() + lasagne.updates.adam(loss_or_grads=loss, params=params, learning_rate=LR).items())
        
    else:
        params = lasagne.layers.get_all_params(cnn, trainable=True)
        updates = lasagne.updates.adam(loss_or_grads=loss, params=params, learning_rate=LR)

    test_output = lasagne.layers.get_output(cnn, deterministic=True)
    test_loss = T.mean(T.sqr(T.maximum(0.,1.-target*test_output)))
    test_err = T.mean(T.neq(T.argmax(test_output, axis=1), T.argmax(target, axis=1)),dtype=theano.config.floatX)
    
    # Compile a function performing a training step on a mini-batch (by giving the updates dictionary) 
    # and returning the corresponding training loss:
    train_fn = theano.function([input, target, LR], loss, updates=updates)

    # Compile a second function computing the validation loss and accuracy:
    val_fn = theano.function([input, target], [test_loss, test_err])

    print('Training...')
    
    binary_connect.train(
            train_fn,val_fn,
            batch_size,
            LR_start,LR_decay,
            num_epochs,
            train_set.X,train_set.y,
            valid_set.X,valid_set.y,
            test_set.X,test_set.y)
    
    # print("display histogram")
    
    # W = lasagne.layers.get_all_layers(mlp)[2].W.get_value()
    # print(W.shape)
    
    # histogram = np.histogram(W,bins=1000,range=(-1.1,1.1))
    # np.savetxt(str(dropout_hidden)+str(binary)+str(stochastic)+str(H)+"_hist0.csv", histogram[0], delimiter=",")
    # np.savetxt(str(dropout_hidden)+str(binary)+str(stochastic)+str(H)+"_hist1.csv", histogram[1], delimiter=",")
    
    # Optionally, you could now dump the network weights to a file like this:
    # np.savez('model.npz', lasagne.layers.get_all_param_values(network))