JittorMirror/python/jittor/models/res2net.py

185 lines
6.7 KiB
Python

import jittor as jt
from jittor import nn
from jittor import Module
from jittor import init
from jittor.contrib import concat, argmax_pool
import math
class Bottle2neck(nn.Module):
expansion = 4
def __init__(self, inplanes, planes, stride=1, dilation=1, downsample=None, baseWidth=26, scale = 4, stype='normal'):
""" Constructor
Args:
inplanes: input channel dimensionality
planes: output channel dimensionality
stride: conv stride. Replaces pooling layer.
downsample: None when stride = 1
baseWidth: basic width of conv3x3
scale: number of scale.
type: 'normal': normal set. 'stage': first block of a new stage.
"""
super(Bottle2neck, self).__init__()
width = int(math.floor(planes * (baseWidth/64.0)))
self.conv1 = nn.Conv(inplanes, width*scale, kernel_size=1, bias=False)
self.bn1 = nn.BatchNorm(width*scale)
assert scale > 1, 'Res2Net degenerates to ResNet when scales = 1.'
if scale == 1:
self.nums = 1
else:
self.nums = scale -1
if stype == 'stage':
self.pool = nn.Pool(kernel_size=3, stride = stride, padding=1, op='mean')
self.convs = nn.ModuleList()
self.bns = nn.ModuleList()
for i in range(self.nums):
self.convs.append(nn.Conv(width, width, kernel_size=3, stride = stride, dilation=dilation, padding=dilation, bias=False))
self.bns.append(nn.BatchNorm(width))
self.conv3 = nn.Conv(width*scale, planes * self.expansion, kernel_size=1, bias=False)
self.bn3 = nn.BatchNorm(planes * self.expansion)
self.relu = nn.ReLU()
self.downsample = downsample
self.stype = stype
self.scale = scale
self.width = width
self.stride = stride
self.dilation = dilation
def execute(self, x):
residual = x
out = self.conv1(x)
out = self.bn1(out)
out = self.relu(out)
spx = out
outs = []
for i in range(self.nums):
if i==0 or self.stype=='stage':
sp = spx[:, i*self.width: (i+1)*self.width]
else:
sp = sp + spx[:, i*self.width: (i+1)*self.width]
sp = self.convs[i](sp)
sp = self.relu(self.bns[i](sp))
outs.append(sp)
if self.stype=='normal' or self.stride==1:
outs.append(spx[:, self.nums*self.width: (self.nums+1)*self.width])
elif self.stype=='stage':
outs.append(self.pool(spx[:, self.nums*self.width: (self.nums+1)*self.width]))
out = concat(outs, 1)
out = self.conv3(out)
out = self.bn3(out)
if self.downsample is not None:
residual = self.downsample(x)
out += residual
out = self.relu(out)
return out
class Res2Net(Module):
def __init__(self, block, layers, output_stride, baseWidth = 26, scale = 4):
super(Res2Net, self).__init__()
self.baseWidth = baseWidth
self.scale = scale
self.inplanes = 64
blocks = [1, 2, 4]
if output_stride == 16:
strides = [1, 2, 2, 1]
dilations = [1, 1, 1, 2]
elif output_stride == 8:
strides = [1, 2, 1, 1]
dilations = [1, 1, 2, 4]
else:
raise NotImplementedError
# Modules
self.conv1 = nn.Sequential(
nn.Conv(3, 32, 3, 2, 1, bias=False),
nn.BatchNorm(32),
nn.ReLU(),
nn.Conv(32, 32, 3, 1, 1, bias=False),
nn.BatchNorm(32),
nn.ReLU(),
nn.Conv(32, 64, 3, 1, 1, bias=False)
)
self.bn1 = nn.BatchNorm(64)
self.relu = nn.ReLU()
# self.maxpool = nn.Pool(kernel_size=3, stride=2, padding=1)
self.layer1 = self._make_layer(block, 64, layers[0], stride=strides[0], dilation=dilations[0])
self.layer2 = self._make_layer(block, 128, layers[1], stride=strides[1], dilation=dilations[1])
self.layer3 = self._make_layer(block, 256, layers[2], stride=strides[2], dilation=dilations[2])
self.layer4 = self._make_MG_unit(block, 512, blocks=blocks, stride=strides[3], dilation=dilations[3])
def _make_layer(self, block, planes, blocks, stride=1, dilation=1):
downsample = None
if stride != 1 or self.inplanes != planes * block.expansion:
downsample = nn.Sequential(
nn.Pool(kernel_size=stride, stride=stride,
ceil_mode=True, op='mean'),
nn.Conv(self.inplanes, planes * block.expansion,
kernel_size=1, stride=1, bias=False),
nn.BatchNorm(planes * block.expansion),
)
layers = []
layers.append(block(self.inplanes, planes, stride, dilation, downsample,
stype='stage', baseWidth = self.baseWidth, scale=self.scale))
self.inplanes = planes * block.expansion
for i in range(1, blocks):
layers.append(block(self.inplanes, planes, dilation=dilation, baseWidth = self.baseWidth, scale=self.scale))
return nn.Sequential(*layers)
def _make_MG_unit(self, block, planes, blocks, stride=1, dilation=1):
downsample = None
if stride != 1 or self.inplanes != planes * block.expansion:
downsample = nn.Sequential(
nn.Pool(kernel_size=stride, stride=stride,
ceil_mode=True, op='mean'),
nn.Conv(self.inplanes, planes * block.expansion,
kernel_size=1, stride=1, bias=False),
nn.BatchNorm(planes * block.expansion),
)
layers = []
layers.append(block(self.inplanes, planes, stride, dilation=blocks[0]*dilation,
downsample=downsample, stype='stage', baseWidth = self.baseWidth, scale=self.scale))
self.inplanes = planes * block.expansion
for i in range(1, len(blocks)):
layers.append(block(self.inplanes, planes, stride=1,
dilation=blocks[i]*dilation, baseWidth = self.baseWidth, scale=self.scale))
return nn.Sequential(*layers)
def execute(self, input):
x = self.conv1(input)
x = self.bn1(x)
x = self.relu(x)
x = argmax_pool(x, 2, 2)
x = self.layer1(x)
low_level_feat = x
x = self.layer2(x)
x = self.layer3(x)
x = self.layer4(x)
return x, low_level_feat
def res2net50(output_stride=16):
model = Res2Net(Bottle2neck, [3,4,6,3], output_stride)
return model
def res2net101(output_stride=16):
model = Res2Net(Bottle2neck, [3,4,23,3], output_stride)
return model