Files
2021-02-25 20:32:44 +05:30

183 lines
6.5 KiB
Python

#!/bin/python
import torch
import torch.nn as nn
import torchvision
import torchvision.transforms as transforms
import torch.optim as optim
from torchsummary import summary
#custom import
import numpy as np
import time
import os
# ResBlock
class ResBlock(nn.Module):
def __init__(self, num_features, use_batch_norm=False):
super(ResBlock, self).__init__()
self.num_features = num_features
self.conv_layer1 = nn.Conv2d(num_features, num_features, kernel_size=3, stride=1, padding=1)
self.relu_layer = nn.ReLU()
self.conv_layer2 = nn.Conv2d(num_features, num_features, kernel_size=3, stride=1, padding=1)
self.use_batch_norm = use_batch_norm
if self.use_batch_norm:
self.batch_norm_layer1 = nn.BatchNorm2d(self.num_features)
self.batch_norm_layer2 = nn.BatchNorm2d(self.num_features)
for m in self.modules():
if isinstance(m, nn.Conv2d):
nn.init.kaiming_normal_(m.weight)
# nn.init.xavier_uniform_(m.weight)
def forward(self, x):
residual = x
x = self.conv_layer1(x)
if self.use_batch_norm:
x = self.batch_norm_layer1(x)
x = self.relu_layer(x)
x = self.conv_layer2(x)
if self.use_batch_norm:
x = self.batch_norm_layer2(x)
x += residual
x = self.relu_layer(x)
return x
# ResNet
class ResNet(nn.Module):
def __init__(self, in_features, num_class, feature_channel_list, batch_norm= False, num_stacks=1, zero_init_residual=True):
super(ResNet, self).__init__()
self.in_features = in_features
self.num_in_channel = in_features[2]
self.num_class = num_class
self.feature_channel_list = feature_channel_list
self.num_residual_blocks = len(self.feature_channel_list)
self.num_stacks = num_stacks
self.batch_norm = batch_norm
self.shape_list = []
self.shape_list.append(in_features)
self.module_list = nn.ModuleList()
self.zero_init_residual= zero_init_residual
self.build_()
def build_(self):
#track filter shape
cur_shape = self.GetCurShape()
cur_shape = self.CalcConvOutShape(cur_shape, kernel_size=7, padding=1, stride=2, out_filters= self.feature_channel_list[0])
self.shape_list.append(cur_shape)
if len(self.in_features) == 2:
in_channels = 1
else:
in_channels = self.in_features[2]
# First Conv layer 7x7 stride=2, pad =1
self.module_list.append(nn.Conv2d(in_channels= in_channels,
out_channels= self.feature_channel_list[0],
kernel_size=7,
stride=2,
padding=3))
#batch norm
if self.batch_norm: #batch_norm
self.module_list.append(nn.BatchNorm2d(self.feature_channel_list[0]))
# ReLU()
self.module_list.append(nn.ReLU())
for i in range(self.num_residual_blocks-1):
in_size = self.feature_channel_list[i]
out_size = self.feature_channel_list[i+1]
res_block = ResBlock(in_size, use_batch_norm=True)
# #Stacking Residual blocks
for num in range(self.num_stacks):
self.module_list.append(res_block)
# # Intermediate Conv and ReLU()
self.module_list.append(nn.Conv2d(in_channels=in_size,
out_channels= out_size,
kernel_size=3,
padding=1,
stride=2))
# track filter shape
cur_shape = self.CalcConvOutShape(cur_shape, kernel_size=3, padding=1,
stride=2, out_filters=out_size)
self.shape_list.append(cur_shape)
# # batch norm
if self.batch_norm: # batch_norm
self.module_list.append(nn.BatchNorm2d(out_size))
self.module_list.append(nn.ReLU())
# print("shape list", self.shape_list)
#TODO include in the main loop
#Last Residual block
res_block = ResBlock(out_size, use_batch_norm=True)
for num in range(self.num_stacks):
self.module_list.append(res_block)
#Last AvgPool layer
# self.module_list.append(nn.AvgPool2d(kernel_size=2, stride=2, padding=0))
self.module_list.append(nn.MaxPool2d(kernel_size=2, stride=2, padding=0))
# track filter shape
cur_shape = self.CalcConvOutShape(cur_shape, kernel_size=2, padding=0, stride=2, out_filters=out_size)
self.shape_list.append(cur_shape)
s = self.GetCurShape()
in_features = s[0] * s[1] * s[2]
# Initialization
for m in self.modules():
if isinstance(m, nn.Conv2d):
nn.init.kaiming_normal_(m.weight)
# nn.init.xavier_uniform_(m.weight)
# if self.zero_init_residual:
# for m in self.modules():
# if isinstance(m, ResBlock):
# nn.init.constant_(m.batch_norm_layer1.weight, 0)
# nn.init.constant_(m.batch_norm_layer2.weight, 0)
def GetCurShape(self):
return self.shape_list[-1]
def CalcConvFormula(self, W, K, P, S):
return int(np.floor(((W - K + 2 * P) / S) + 1))
# https://stackoverflow.com/questions/53580088/calculate-the-output-size-in-convolution-layer
# Calculate the output shape after applying a convolution
def CalcConvOutShape(self, in_shape, kernel_size, padding, stride, out_filters):
# Multiple options for different kernel shapes
if type(kernel_size) == int:
out_shape = [self.CalcConvFormula(in_shape[i], kernel_size, padding, stride) for i in range(2)]
else:
out_shape = [self.CalcConvFormula(in_shape[i], kernel_size[i], padding, stride) for i in range(2)]
return (out_shape[0], out_shape[1], out_filters) # , batch_size... but not necessary.
def AddMLP(self, MLP):
if MLP:
self.module_list.append(MLP)
# def MLP(self, in_features, num_classes, use_batch_norm=False, use_dropout=False, use_softmax=False):
# return nn.ReLU(nn.Linear(in_features, num_classes))
def forward(self, x):
for mod_name in self.module_list:
x = mod_name(x)
x = x.view(x.size(0), -1) # flat #TODO check if it works
return x