diff --git a/demo/gan/gan_conf_image.py b/demo/gan/gan_conf_image.py
index 83fa34fabcf83b5c55a853d2800620e086b8045a..e811bb96e88aefcd5ec510ea5c77ca4f35adfc47 100644
--- a/demo/gan/gan_conf_image.py
+++ b/demo/gan/gan_conf_image.py
@@ -232,8 +232,13 @@ if is_discriminator_training:
     sample = data_layer(name="sample", size=sample_dim * sample_dim*c_dim)
 
 if is_generator_training or is_discriminator_training:
+    sample_noise = data_layer(name="sample_noise", 
+                              size=sample_dim * sample_dim * c_dim)
     label = data_layer(name="label", size=1)
-    prob = discriminator(sample)
+    prob = discriminator(addto_layer([sample, sample_noise], 
+                                     act=LinearActivation(), 
+                                     name="add", 
+                                     bias_attr=False))
     cost = cross_entropy(input=prob, label=label)
     classification_error_evaluator(input=prob, label=label, name=mode+'_error')
     outputs(cost)
diff --git a/demo/gan/gan_trainer_image.py b/demo/gan/gan_trainer_image.py
index 51bbbe8f1f4e1a860a076b41402b45a026be189b..9c7ddd4796fd62c2e1f6877cb3a74378be5dcab1 100644
--- a/demo/gan/gan_trainer_image.py
+++ b/demo/gan/gan_trainer_image.py
@@ -115,9 +115,13 @@ def get_real_samples(batch_size, data_np):
 def get_noise(batch_size, noise_dim):
     return numpy.random.normal(size=(batch_size, noise_dim)).astype('float32')
 
+def get_sample_noise(batch_size):
+    return numpy.random.normal(size=(batch_size, 28*28),
+                               scale=0.1).astype('float32')
+
 def get_fake_samples(generator_machine, batch_size, noise):
-    gen_inputs = prepare_generator_data_batch(batch_size, noise)
-    gen_inputs.resize(1)
+    gen_inputs = api.Arguments.createArguments(1)
+    gen_inputs.setSlotValue(0, api.Matrix.createGpuDenseFromNumpy(noise))
     gen_outputs = api.Arguments.createArguments(0)
     generator_machine.forward(gen_inputs, gen_outputs, api.PASS_TEST)
     fake_samples = gen_outputs.getSlotValue(0).copyToNumpyMat()
@@ -129,29 +133,33 @@ def get_training_loss(training_machine, inputs):
     loss = outputs.getSlotValue(0).copyToNumpyMat()
     return numpy.mean(loss)
 
-def prepare_discriminator_data_batch_pos(batch_size, data_np):
+def prepare_discriminator_data_batch_pos(batch_size, data_np, sample_noise):
     real_samples = get_real_samples(batch_size, data_np)
     labels = numpy.ones(batch_size, dtype='int32')
-    inputs = api.Arguments.createArguments(2)
+    inputs = api.Arguments.createArguments(3)
     inputs.setSlotValue(0, api.Matrix.createGpuDenseFromNumpy(real_samples))
-    inputs.setSlotIds(1, api.IVector.createGpuVectorFromNumpy(labels))
+    inputs.setSlotValue(1, api.Matrix.createGpuDenseFromNumpy(sample_noise))
+    inputs.setSlotIds(2, api.IVector.createGpuVectorFromNumpy(labels))
     return inputs
 
-def prepare_discriminator_data_batch_neg(generator_machine, batch_size, noise):
+def prepare_discriminator_data_batch_neg(generator_machine, batch_size, noise,
+                                         sample_noise):
     fake_samples = get_fake_samples(generator_machine, batch_size, noise)
     #print fake_samples.shape
     labels = numpy.zeros(batch_size, dtype='int32')
-    inputs = api.Arguments.createArguments(2)
+    inputs = api.Arguments.createArguments(3)
     inputs.setSlotValue(0, api.Matrix.createGpuDenseFromNumpy(fake_samples))
-    inputs.setSlotIds(1, api.IVector.createGpuVectorFromNumpy(labels))
+    inputs.setSlotValue(1, api.Matrix.createGpuDenseFromNumpy(sample_noise))
+    inputs.setSlotIds(2, api.IVector.createGpuVectorFromNumpy(labels))
     return inputs
 
-def prepare_generator_data_batch(batch_size, noise):
+def prepare_generator_data_batch(batch_size, noise, sample_noise):
     label = numpy.ones(batch_size, dtype='int32')
     #label = numpy.zeros(batch_size, dtype='int32')
-    inputs = api.Arguments.createArguments(2)
+    inputs = api.Arguments.createArguments(3)
     inputs.setSlotValue(0, api.Matrix.createGpuDenseFromNumpy(noise))
-    inputs.setSlotIds(1, api.IVector.createGpuVectorFromNumpy(label))
+    inputs.setSlotValue(1, api.Matrix.createGpuDenseFromNumpy(sample_noise))
+    inputs.setSlotIds(2, api.IVector.createGpuVectorFromNumpy(label))
     return inputs
 
 
@@ -216,25 +224,27 @@ def main():
 #                     generator_machine, batch_size, noise_dim, sample_dim)
 #             dis_loss = get_training_loss(dis_training_machine, data_batch_dis)
             noise = get_noise(batch_size, noise_dim)
+            sample_noise = get_sample_noise(batch_size)
             data_batch_dis_pos = prepare_discriminator_data_batch_pos(
-                batch_size, data_np)
+                batch_size, data_np, sample_noise)
             dis_loss_pos = get_training_loss(dis_training_machine, data_batch_dis_pos)
-                        
+            
+            sample_noise = get_sample_noise(batch_size)   
             data_batch_dis_neg = prepare_discriminator_data_batch_neg(
-                generator_machine, batch_size, noise)
+                generator_machine, batch_size, noise, sample_noise)
             dis_loss_neg = get_training_loss(dis_training_machine, data_batch_dis_neg)            
                          
             dis_loss = (dis_loss_pos + dis_loss_neg) / 2.0
              
             data_batch_gen = prepare_generator_data_batch(
-                    batch_size, noise)
+                    batch_size, noise, sample_noise)
             gen_loss = get_training_loss(gen_training_machine, data_batch_gen)
              
             if i % 100 == 0:
                 print "d_pos_loss is %s     d_neg_loss is %s" % (dis_loss_pos, dis_loss_neg) 
                 print "d_loss is %s    g_loss is %s" % (dis_loss, gen_loss)
                              
-            if (not (curr_train == "dis" and curr_strike == MAX_strike)) and ((curr_train == "gen" and curr_strike == MAX_strike) or dis_loss > gen_loss):
+            if (not (curr_train == "dis" and curr_strike == MAX_strike)) and ((curr_train == "gen" and curr_strike == MAX_strike) or dis_loss_neg > gen_loss):
                 if curr_train == "dis":
                     curr_strike += 1
                 else: