diff deep/convolutional_dae/salah_exp/stacked_convolutional_dae_uit.py @ 358:31641a84e0ae

Initial commit for the experimental setup of the denoising convolutional network
author humel
date Thu, 22 Apr 2010 00:49:42 -0400
parents
children c05680f8c92f
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line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/deep/convolutional_dae/salah_exp/stacked_convolutional_dae_uit.py	Thu Apr 22 00:49:42 2010 -0400
@@ -0,0 +1,242 @@
+import numpy
+import theano
+import time
+import sys
+import theano.tensor as T
+from theano.tensor.shared_randomstreams import RandomStreams
+import theano.sandbox.softsign
+import copy
+from theano.tensor.signal import downsample
+from theano.tensor.nnet import conv 
+
+
+import ift6266.datasets
+from ift6266.baseline.log_reg.log_reg import LogisticRegression
+
+from theano.tensor.xlogx import xlogx, xlogy0
+# it's target*log(output)
+def binary_cross_entropy(target, output, sum_axis=1):
+    XE = xlogy0(target, output) + xlogy0((1 - target), (1 - output))
+    return -T.sum(XE, axis=sum_axis)
+
+
+
+class SigmoidalLayer(object):
+    def __init__(self, rng, input, n_in, n_out):
+
+        self.input = input
+
+        W_values = numpy.asarray( rng.uniform( \
+              low = -numpy.sqrt(6./(n_in+n_out)), \
+              high = numpy.sqrt(6./(n_in+n_out)), \
+              size = (n_in, n_out)), dtype = theano.config.floatX)
+        self.W = theano.shared(value = W_values)
+ 
+        b_values = numpy.zeros((n_out,), dtype= theano.config.floatX)
+        self.b = theano.shared(value= b_values)
+ 
+        self.output = T.tanh(T.dot(input, self.W) + self.b)
+        self.params = [self.W, self.b]
+ 
+class dA_conv(object):
+ 
+  def __init__(self, input, filter_shape, corruption_level = 0.1, 
+               shared_W = None, shared_b = None, image_shape = None, num = 0,batch_size=20):
+
+    theano_rng = RandomStreams()
+    
+    fan_in = numpy.prod(filter_shape[1:])
+    fan_out = filter_shape[0] * numpy.prod(filter_shape[2:])
+
+    center = theano.shared(value = 1, name="center")
+    scale = theano.shared(value = 2, name="scale")
+
+    if shared_W != None and shared_b != None :
+        self.W = shared_W
+        self.b = shared_b
+    else:
+        initial_W = numpy.asarray( numpy.random.uniform(
+              low = -numpy.sqrt(6./(fan_in+fan_out)),
+              high = numpy.sqrt(6./(fan_in+fan_out)),
+              size = filter_shape), dtype = theano.config.floatX)
+        initial_b = numpy.zeros((filter_shape[0],), dtype=theano.config.floatX)
+        self.W = theano.shared(value = initial_W, name = "W")
+        self.b = theano.shared(value = initial_b, name = "b")
+    
+ 
+    initial_b_prime= numpy.zeros((filter_shape[1],),dtype=theano.config.floatX)
+
+    self.b_prime = theano.shared(value = initial_b_prime, name = "b_prime")
+ 
+    self.x = input
+
+    self.tilde_x = theano_rng.binomial( self.x.shape, 1, 1 - corruption_level,dtype=theano.config.floatX) * self.x
+
+    conv1_out = conv.conv2d(self.tilde_x, self.W, filter_shape=filter_shape,
+                            image_shape=image_shape,
+                            unroll_kern=4,unroll_batch=4, 
+                            border_mode='valid')
+
+    
+    self.y = T.tanh(conv1_out + self.b.dimshuffle('x', 0, 'x', 'x'))
+
+    
+    da_filter_shape = [ filter_shape[1], filter_shape[0], filter_shape[2],\
+                       filter_shape[3] ]
+    da_image_shape = [ batch_size, filter_shape[0], image_shape[2]-filter_shape[2]+1, 
+                       image_shape[3]-filter_shape[3]+1 ]
+    #import pdb; pdb.set_trace()
+    initial_W_prime =  numpy.asarray( numpy.random.uniform( \
+              low = -numpy.sqrt(6./(fan_in+fan_out)), \
+              high = numpy.sqrt(6./(fan_in+fan_out)), \
+              size = da_filter_shape), dtype = theano.config.floatX)
+    self.W_prime = theano.shared(value = initial_W_prime, name = "W_prime")
+
+    conv2_out = conv.conv2d(self.y, self.W_prime,
+                            filter_shape = da_filter_shape,\
+                            image_shape = da_image_shape, \
+                            unroll_kern=4,unroll_batch=4, \
+                            border_mode='full')
+
+    self.z =  (T.tanh(conv2_out + self.b_prime.dimshuffle('x', 0, 'x', 'x'))+center) / scale
+    
+    if num != 0 :
+        scaled_x = (self.x + center) / scale
+    else: 
+        scaled_x = self.x
+    self.L = - T.sum( scaled_x*T.log(self.z) + (1-scaled_x)*T.log(1-self.z), axis=1 )
+
+    self.cost = T.mean(self.L)
+
+    self.params = [ self.W, self.b, self.b_prime ] 
+
+class LeNetConvPoolLayer(object):
+
+    def __init__(self, rng, input, filter_shape, image_shape=None, poolsize=(2,2)):
+        self.input = input
+  
+        W_values = numpy.zeros(filter_shape, dtype=theano.config.floatX)
+        self.W = theano.shared(value=W_values)
+ 
+        b_values = numpy.zeros((filter_shape[0],), dtype=theano.config.floatX)
+        self.b = theano.shared(value=b_values)
+ 
+        conv_out = conv.conv2d(input, self.W,
+                filter_shape=filter_shape, image_shape=image_shape,
+                               unroll_kern=4,unroll_batch=4)
+ 
+
+        fan_in = numpy.prod(filter_shape[1:])
+        fan_out = filter_shape[0] * numpy.prod(filter_shape[2:]) / numpy.prod(poolsize)
+
+        W_bound = numpy.sqrt(6./(fan_in + fan_out))
+        self.W.value = numpy.asarray(
+                rng.uniform(low=-W_bound, high=W_bound, size=filter_shape),
+                dtype = theano.config.floatX)
+  
+
+        pooled_out = downsample.max_pool2D(conv_out, poolsize, ignore_border=True)
+ 
+        self.output = T.tanh(pooled_out + self.b.dimshuffle('x', 0, 'x', 'x'))
+        self.params = [self.W, self.b]
+ 
+
+class CSdA():
+    def __init__(self, n_ins_mlp,batch_size, conv_hidden_layers_sizes,
+                 mlp_hidden_layers_sizes, corruption_levels, rng, n_out, 
+                 pretrain_lr, finetune_lr):
+
+        # Just to make sure those are not modified somewhere else afterwards
+        hidden_layers_sizes = copy.deepcopy(mlp_hidden_layers_sizes)
+        corruption_levels = copy.deepcopy(corruption_levels)
+
+        #update_locals(self, locals())
+
+
+        
+        self.layers = []
+        self.pretrain_functions = []
+        self.params = []
+        self.n_layers = len(conv_hidden_layers_sizes)
+        self.mlp_n_layers = len(mlp_hidden_layers_sizes)
+        
+        self.x = T.matrix('x') # the data is presented as rasterized images
+        self.y = T.ivector('y') # the labels are presented as 1D vector of
+        
+        for i in xrange( self.n_layers ):
+            filter_shape=conv_hidden_layers_sizes[i][0]
+            image_shape=conv_hidden_layers_sizes[i][1]
+            max_poolsize=conv_hidden_layers_sizes[i][2]
+                
+            if i == 0 :
+                layer_input=self.x.reshape((batch_size, 1, 32, 32))
+            else:
+                layer_input=self.layers[-1].output
+            
+            layer = LeNetConvPoolLayer(rng, input=layer_input,
+                                       image_shape=image_shape,
+                                       filter_shape=filter_shape,
+                                       poolsize=max_poolsize)
+            print 'Convolutional layer', str(i+1), 'created'
+            
+            self.layers += [layer]
+            self.params += layer.params
+
+            da_layer = dA_conv(corruption_level = corruption_levels[0],
+                               input = layer_input,
+                               shared_W = layer.W, shared_b = layer.b,
+                               filter_shape=filter_shape,
+                               image_shape = image_shape, num=i , batch_size=batch_size)
+            
+            gparams = T.grad(da_layer.cost, da_layer.params)
+            
+            updates = {}
+            for param, gparam in zip(da_layer.params, gparams):
+                updates[param] = param - gparam * pretrain_lr
+            
+            update_fn = theano.function([self.x], da_layer.cost, updates = updates)
+            
+            self.pretrain_functions += [update_fn]
+            
+        for i in xrange( self.mlp_n_layers ): 
+            if i == 0 :
+                input_size = n_ins_mlp
+            else:
+                input_size = mlp_hidden_layers_sizes[i-1]
+            
+            if i == 0 :
+                if len( self.layers ) == 0 :
+                    layer_input=self.x
+                else :
+                    layer_input = self.layers[-1].output.flatten(2)
+            else:
+                layer_input = self.layers[-1].output
+            
+            layer = SigmoidalLayer(rng, layer_input, input_size,
+                                        mlp_hidden_layers_sizes[i] )
+            
+            self.layers += [layer]
+            self.params += layer.params
+            
+            print 'MLP layer', str(i+1), 'created'
+            
+        self.logLayer = LogisticRegression(input=self.layers[-1].output, \
+                                                     n_in=mlp_hidden_layers_sizes[-1], n_out=n_out)
+
+
+        self.params += self.logLayer.params
+        self.all_params = self.params
+        cost = self.logLayer.negative_log_likelihood(self.y)
+        
+        gparams = T.grad(cost, self.params)
+
+        updates = {}
+        for param,gparam in zip(self.params, gparams):
+            updates[param] = param - gparam*finetune_lr
+        
+        self.finetune = theano.function([self.x, self.y], cost, updates = updates)
+        
+        self.errors = self.logLayer.errors(self.y)
+
+
+