#coding=utf-8
from collections import OrderedDict
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.nn import init
import time
def _make_divisible(v, divisor, min_value=None):
"""
This function is taken from the original tf repo.
It ensures that all layers have a channel number that is divisible by 8
It can be seen here:
https://github.com/tensorflow/models/blob/master/research/slim/nets/mobilenet/mobilenet.py
:param v:
:param divisor:
:param min_value:
:return:
"""
if min_value is None:
min_value = divisor
new_v = max(min_value, int(v + divisor / 2.0) // divisor * divisor)
# Make sure that round down does not go down by more than 10%.
if new_v < 0.9 * v:
new_v += divisor
return new_v
class SELayer(nn.Module):
def __init__(self, channel, reduction=16):
super(SELayer, self).__init__()
self.avg_pool = nn.AdaptiveAvgPool2d(1)
self.fc = nn.Sequential(
nn.Linear(channel, channel // reduction),
nn.ReLU(inplace=True),
nn.Linear(channel // reduction, channel),
nn.Sigmoid()
)
def forward(self, x):
b, c, _, _ = x.size()
y = self.avg_pool(x).view(b, c)
y = self.fc(y).view(b, c, 1, 1)
return x * y
@torch.jit.script
def channel_shuffle(x, groups):
batchsize, num_channels, height, width = x.size()
# assert (num_channels % groups == 0)
channels_per_group = num_channels //2# groups
# reshape
print('DownsampleUnit',num_channels, groups.item(), channels_per_group, height, width)
x = x.view(batchsize, 2, channels_per_group, height, width)
# transpose
# - contiguous() required if transpose() is used before view().
# See https://github.com/pytorch/pytorch/issues/764
x = torch.transpose(x, 1, 2).contiguous()
# flatten
x = x.view(batchsize, -1, height, width)
return x
class BasicUnit(torch.jit.ScriptModule):
__constants__ = ['groups', 'left_part', 'residual', 'inplanes', 'outplanes']
def __init__(self, inplanes, outplanes, c_tag=0.5, activation=nn.ReLU, SE=False, residual=False, groups=2):
super(BasicUnit, self).__init__()
self.left_part = int(round(c_tag * inplanes))
self.right_part_in = inplanes - self.left_part
self.right_part_out = outplanes - self.left_part
self.conv1 = nn.Conv2d(self.right_part_in, self.right_part_out, kernel_size=1, bias=False)
self.bn1 = nn.BatchNorm2d(self.right_part_out)
self.conv2 = nn.Conv2d(self.right_part_out, self.right_part_out, kernel_size=3, padding=1, bias=False,
groups=self.right_part_out)
self.bn2 = nn.BatchNorm2d(self.right_part_out)
self.conv3 = nn.Conv2d(self.right_part_out, self.right_part_out, kernel_size=1, bias=False)
self.bn3 = nn.BatchNorm2d(self.right_part_out)
self.activation = activation(inplace=True)
self.inplanes = inplanes
self.outplanes = outplanes
self.residual = residual
self.groups = groups
# self.SE = SE
# if self.SE:
# self.SELayer = SELayer(self.right_part_out, 2) # TODO
@torch.jit.script_method
def forward(self, x):
left = x[:, :self.left_part, :, :]
right = x[:, self.left_part:, :, :]
out = self.conv1(right)
out = self.bn1(out)
out = self.activation(out)
out = self.conv2(out)
out = self.bn2(out)
out = self.conv3(out)
out = self.bn3(out)
out = self.activation(out)
# if self.SE:
# out = self.SELayer(out)
if self.residual and self.inplanes == self.outplanes:
out += right
return channel_shuffle(torch.cat((left, out), 1), torch.ones(1)+1)
class DownsampleUnit(torch.jit.ScriptModule):
__constants__ = ['groups']
def __init__(self, inplanes, c_tag=0.5, activation=nn.ReLU, groups=2):
super(DownsampleUnit, self).__init__()
self.conv1r = nn.Conv2d(inplanes, inplanes, kernel_size=1, bias=False)
self.bn1r = nn.BatchNorm2d(inplanes)
self.conv2r = nn.Conv2d(inplanes, inplanes, kernel_size=3, stride=2, padding=1, bias=False, groups=inplanes)
self.bn2r = nn.BatchNorm2d(inplanes)
self.conv3r = nn.Conv2d(inplanes, inplanes, kernel_size=1, bias=False)
self.bn3r = nn.BatchNorm2d(inplanes)
self.conv1l = nn.Conv2d(inplanes, inplanes, kernel_size=3, stride=2, padding=1, bias=False, groups=inplanes)
self.bn1l = nn.BatchNorm2d(inplanes)
self.conv2l = nn.Conv2d(inplanes, inplanes, kernel_size=1, bias=False)
self.bn2l = nn.BatchNorm2d(inplanes)
self.activation = activation(inplace=True)
self.groups = groups
self.inplanes = inplanes
@torch.jit.script_method
def forward(self, x):
out_r = self.conv1r(x)
out_r = self.bn1r(out_r)
out_r = self.activation(out_r)
out_r = self.conv2r(out_r)
out_r = self.bn2r(out_r)
out_r = self.conv3r(out_r)
out_r = self.bn3r(out_r)
out_r = self.activation(out_r)
out_l = self.conv1l(x)
out_l = self.bn1l(out_l)
out_l = self.conv2l(out_l)
out_l = self.bn2l(out_l)
out_l = self.activation(out_l)
# print(out_l.shape)
return channel_shuffle(torch.cat((out_r, out_l), 1), torch.ones(1)+1)
class ShuffleNetV2(torch.jit.ScriptModule):
__constants__ = ['shuffles']
def __init__(self, scale=1.0, in_channels=3, c_tag=0.5, num_classes=1000, activation=nn.ReLU,
SE=False, residual=False, groups=2):
"""
ShuffleNetV2 constructor
:param scale:
:param in_channels:
:param c_tag:
:param num_classes:
:param activation:
:param SE:
:param residual:
:param groups:
"""
super(ShuffleNetV2, self).__init__()
self.scale = scale
self.c_tag = c_tag
self.residual = residual
self.SE = SE
self.groups = groups
self.activation_type = activation
self.activation = activation(inplace=True)
self.num_classes = num_classes
# self.layers_out_filters = [116, 232, 1024]
self.num_of_channels = {0.5: [24, 48, 96, 192, 1024], 1: [24, 116, 232, 464, 1024],
1.5: [24, 176, 352, 704, 1024], 2: [24, 244, 488, 976, 2048]}
self.layers_out_filters=self.num_of_channels[scale][1:4]
self.cc = [_make_divisible(chan, groups) for chan in self.num_of_channels[scale]]
self.n = [3, 8, 3] # TODO: should be [3,7,3]
self.conv1 = nn.Conv2d(in_channels, self.cc[0], kernel_size=3, bias=False, stride=2, padding=1)
self.bn1 = nn.BatchNorm2d(self.cc[0])
self.bn2 = nn.BatchNorm2d(self.cc[1])
self.bn3 = nn.BatchNorm2d(self.cc[2])
self.maxpool = nn.MaxPool2d(kernel_size=3, stride=2)
self.shuffles = self._make_shuffles()
self.activation1=nn.LeakyReLU()
# # self.conv_last = nn.Conv2d(self.c[-2], self.c[-1], kernel_size=1, bias=False)
self.bn_last = nn.BatchNorm2d(self.cc[-2])
# self.avgpool = nn.AdaptiveAvgPool2d(1)
# self.fc = nn.Linear(self.c[-1], self.num_classes)
# self.init_params()
def init_params(self):
for m in self.modules():
if isinstance(m, nn.Conv2d):
init.kaiming_normal_(m.weight, mode='fan_out')
if m.bias is not None:
init.constant_(m.bias, 0)
elif isinstance(m, nn.BatchNorm2d):
init.constant_(m.weight, 1)
init.constant_(m.bias, 0)
elif isinstance(m, nn.Linear):
init.normal_(m.weight, std=0.001)
if m.bias is not None:
init.constant_(m.bias, 0)
def _make_stage(self, inplanes, outplanes, n, stage):
modules = OrderedDict()
stage_name = "ShuffleUnit{}".format(stage)
# First module is the only one utilizing stride
first_module = DownsampleUnit(inplanes=inplanes, activation=self.activation_type, c_tag=self.c_tag,
groups=self.groups)
modules["DownsampleUnit"] = first_module
second_module = BasicUnit(inplanes=inplanes * 2, outplanes=outplanes, activation=self.activation_type,
c_tag=self.c_tag, SE=self.SE, residual=self.residual, groups=self.groups)
modules[stage_name + "_{}".format(0)] = second_module
# add more LinearBottleneck depending on number of repeats
for i in range(n - 1):
name = stage_name + "_{}".format(i + 1)
module = BasicUnit(inplanes=outplanes, outplanes=outplanes, activation=self.activation_type,
c_tag=self.c_tag, SE=self.SE, residual=self.residual, groups=self.groups)
modules[name] = module
return nn.Sequential(modules)
def _make_shuffles(self):
modules = OrderedDict()
stage_name = "ShuffleConvs"
for i in range(len(self.cc) - 2):
name = stage_name + "_{}".format(i)
module = self._make_stage(inplanes=self.cc[i], outplanes=self.cc[i + 1], n=self.n[i], stage=i)
modules[name] = module
return nn.Sequential(modules)
@torch.jit.script_method
def forward(self, x):
x = self.conv1(x)
x = self.bn1(x)
x = self.activation(x)
x = self.maxpool(x)
output = []
# return x
i = 0
for module in self.shuffles:
if i == 0:
x = self.bn2(module(x))
output.append(self.activation1(x))
elif i == 1:
# branch = torch.nn.Sequential(list(module[0].named_children())[0][1],list(module[0].named_children())[1][1])
x = self.bn3(module(x))
output.append(self.activation1(x))
else:
x = module(x)
i += 1
#
x = self.bn_last(x)
x = self.activation(x)
return output[0], output[1], x
#這個是速度測試
if __name__ == "__main__":
model = ShuffleNetV2(scale=0.5, in_channels=3, c_tag=0.5, num_classes=2, activation=nn.ReLU,
SE=False, residual=False)
x = torch.rand(1, 3, 352, 352) # .cuda()
traced_script_module = torch.jit.trace(model, x)
traced_script_module.save("c++_model.pt")
# for i in range(4):
# t1 = time.time()
# x = torch.rand(1,3, 352, 352)
# out3, out4, out5 = model(x)
# # print(out3)
# print(out3.size())
# print(out4.size())
# print(out5.size())
# cnt = time.time() - t1
# print(cnt)
