Permalink
Find file
0dda3d1 Jul 7, 2016
137 lines (116 sloc) 5.89 KB
# coding: utf-8
import sys, os
sys.path.append(os.pardir) # 親ディレクトリのファイルをインポートするための設定
import pickle
import numpy as np
from collections import OrderedDict
from common.layers import *
class DeepConvNet:
"""認識率99%以上の高精度なConvNet
ネットワーク構成は下記の通り
conv - relu - conv- relu - pool -
conv - relu - conv- relu - pool -
conv - relu - conv- relu - pool -
affine - relu - dropout - affine - dropout - softmax
"""
def __init__(self, input_dim=(1, 28, 28),
conv_param_1 = {'filter_num':16, 'filter_size':3, 'pad':1, 'stride':1},
conv_param_2 = {'filter_num':16, 'filter_size':3, 'pad':1, 'stride':1},
conv_param_3 = {'filter_num':32, 'filter_size':3, 'pad':1, 'stride':1},
conv_param_4 = {'filter_num':32, 'filter_size':3, 'pad':2, 'stride':1},
conv_param_5 = {'filter_num':64, 'filter_size':3, 'pad':1, 'stride':1},
conv_param_6 = {'filter_num':64, 'filter_size':3, 'pad':1, 'stride':1},
hidden_size=50, output_size=10):
# 重みの初期化===========
# 各層のニューロンひとつあたりが、前層のニューロンといくつのつながりがあるか(TODO:自動で計算する)
pre_node_nums = np.array([1*3*3, 16*3*3, 16*3*3, 32*3*3, 32*3*3, 64*3*3, 64*4*4, hidden_size])
wight_init_scales = np.sqrt(2.0 / pre_node_nums) # ReLUを使う場合に推奨される初期値
self.params = {}
pre_channel_num = input_dim[0]
for idx, conv_param in enumerate([conv_param_1, conv_param_2, conv_param_3, conv_param_4, conv_param_5, conv_param_6]):
self.params['W' + str(idx+1)] = wight_init_scales[idx] * np.random.randn(conv_param['filter_num'], pre_channel_num, conv_param['filter_size'], conv_param['filter_size'])
self.params['b' + str(idx+1)] = np.zeros(conv_param['filter_num'])
pre_channel_num = conv_param['filter_num']
self.params['W7'] = wight_init_scales[6] * np.random.randn(64*4*4, hidden_size)
self.params['b7'] = np.zeros(hidden_size)
self.params['W8'] = wight_init_scales[7] * np.random.randn(hidden_size, output_size)
self.params['b8'] = np.zeros(output_size)
# レイヤの生成===========
self.layers = []
self.layers.append(Convolution(self.params['W1'], self.params['b1'],
conv_param_1['stride'], conv_param_1['pad']))
self.layers.append(Relu())
self.layers.append(Convolution(self.params['W2'], self.params['b2'],
conv_param_2['stride'], conv_param_2['pad']))
self.layers.append(Relu())
self.layers.append(Pooling(pool_h=2, pool_w=2, stride=2))
self.layers.append(Convolution(self.params['W3'], self.params['b3'],
conv_param_3['stride'], conv_param_3['pad']))
self.layers.append(Relu())
self.layers.append(Convolution(self.params['W4'], self.params['b4'],
conv_param_4['stride'], conv_param_4['pad']))
self.layers.append(Relu())
self.layers.append(Pooling(pool_h=2, pool_w=2, stride=2))
self.layers.append(Convolution(self.params['W5'], self.params['b5'],
conv_param_5['stride'], conv_param_5['pad']))
self.layers.append(Relu())
self.layers.append(Convolution(self.params['W6'], self.params['b6'],
conv_param_6['stride'], conv_param_6['pad']))
self.layers.append(Relu())
self.layers.append(Pooling(pool_h=2, pool_w=2, stride=2))
self.layers.append(Affine(self.params['W7'], self.params['b7']))
self.layers.append(Relu())
self.layers.append(Dropout(0.5))
self.layers.append(Affine(self.params['W8'], self.params['b8']))
self.layers.append(Dropout(0.5))
self.last_layer = SoftmaxWithLoss()
def predict(self, x, train_flg=False):
for layer in self.layers:
if isinstance(layer, Dropout):
x = layer.forward(x, train_flg)
else:
x = layer.forward(x)
return x
def loss(self, x, t):
y = self.predict(x, train_flg=True)
return self.last_layer.forward(y, t)
def accuracy(self, x, t, batch_size=100):
if t.ndim != 1 : t = np.argmax(t, axis=1)
acc = 0.0
for i in range(int(x.shape[0] / batch_size)):
tx = x[i*batch_size:(i+1)*batch_size]
tt = t[i*batch_size:(i+1)*batch_size]
y = self.predict(tx, train_flg=False)
y = np.argmax(y, axis=1)
acc += np.sum(y == tt)
return acc / x.shape[0]
def gradient(self, x, t):
# forward
self.loss(x, t)
# backward
dout = 1
dout = self.last_layer.backward(dout)
tmp_layers = self.layers.copy()
tmp_layers.reverse()
for layer in tmp_layers:
dout = layer.backward(dout)
# 設定
grads = {}
for i, layer_idx in enumerate((0, 2, 5, 7, 10, 12, 15, 18)):
grads['W' + str(i+1)] = self.layers[layer_idx].dW
grads['b' + str(i+1)] = self.layers[layer_idx].db
return grads
def save_params(self, file_name="params.pkl"):
params = {}
for key, val in self.params.items():
params[key] = val
with open(file_name, 'wb') as f:
pickle.dump(params, f)
def load_params(self, file_name="params.pkl"):
with open(file_name, 'rb') as f:
params = pickle.load(f)
for key, val in params.items():
self.params[key] = val
for i, layer_idx in enumerate((0, 2, 5, 7, 10, 12, 15, 18)):
self.layers[layer_idx].W = self.params['W' + str(i+1)]
self.layers[layer_idx].b = self.params['b' + str(i+1)]