repvggnet实现花的种类识别

import torch.nn as nn import numpy as np import torch import copy from se_block import SEBlock def conv_bn(in_channels, out_channels, kernel_size, stride, padding, groups=1): result = nn.Sequential() result.add_module('conv', nn.Conv2d(in_channels=in_channels, out_channels=out_channels, kernel_size=kernel_size, stride=stride, padding=padding, groups=groups, bias=False)) result.add_module('bn', nn.BatchNorm2d(num_features=out_channels)) return result class RepVGGBlock(nn.Module): def __init__(self, in_channels, out_channels, kernel_size, stride=1, padding=0, dilation=1, groups=1, padding_mode='zeros', deploy=False, use_se=False): super(RepVGGBlock, self).__init__() self.deploy = deploy self.groups = groups self.in_channels = in_channels assert kernel_size == 3 assert padding == 1 padding_11 = padding - kernel_size // 2 self.nonlinearity = nn.ReLU() if use_se: self.se = SEBlock(out_channels, internal_neurons=out_channels // 16) else: self.se = nn.Identity() if deploy:#是，就只定义3*3卷积 self.rbr_reparam = nn.Conv2d(in_channels=in_channels, out_channels=out_channels, kernel_size=kernel_size, stride=stride, padding=padding, dilation=dilation, groups=groups, bias=True, padding_mode=padding_mode) else:#如果不是展示，定义一个3*3卷积和1*1的卷积和残差结构 self.rbr_identity = nn.BatchNorm2d(num_features=in_channels) if out_channels == in_channels and stride == 1 else None self.rbr_dense = conv_bn(in_channels=in_channels, out_channels=out_channels, kernel_size=kernel_size, stride=stride, padding=padding, groups=groups) self.rbr_1x1 = conv_bn(in_channels=in_channels, out_channels=out_channels, kernel_size=1, stride=stride, padding=padding_11, groups=groups) print('RepVGG Block, identity = ', self.rbr_identity) def forward(self, inputs): if hasattr(self, 'rbr_reparam'): return self.nonlinearity(self.se(self.rbr_reparam(inputs))) if self.rbr_identity is None: id_out = 0 else: id_out = self.rbr_identity(inputs) return self.nonlinearity(self.se(self.rbr_dense(inputs) + self.rbr_1x1(inputs) + id_out)) # Optional. This improves the accuracy and facilitates quantization. # 1. Cancel the original weight decay on rbr_dense.conv.weight and rbr_1x1.conv.weight. # 2. Use like this. # loss = criterion(....) # for every RepVGGBlock blk: # loss += weight_decay_coefficient * 0.5 * blk.get_cust_L2() # optimizer.zero_grad() # loss.backward() def get_custom_L2(self):#L2正则化 K3 = self.rbr_dense.conv.weight K1 = self.rbr_1x1.conv.weight t3 = (self.rbr_dense.bn.weight / ((self.rbr_dense.bn.running_var + self.rbr_dense.bn.eps).sqrt())).reshape(-1, 1, 1, 1).detach() t1 = (self.rbr_1x1.bn.weight / ((self.rbr_1x1.bn.running_var + self.rbr_1x1.bn.eps).sqrt())).reshape(-1, 1, 1, 1).detach() l2_loss_circle = (K3 ** 2).sum() - (K3[:, :, 1:2, 1:2] ** 2).sum() # The L2 loss of the "circle" of weights in 3x3 kernel. Use regular L2 on them. eq_kernel = K3[:, :, 1:2, 1:2] * t3 + K1 * t1 # The equivalent resultant central point of 3x3 kernel. l2_loss_eq_kernel = (eq_kernel ** 2 / (t3 ** 2 + t1 ** 2)).sum() # Normalize for an L2 coefficient comparable to regular L2. return l2_loss_eq_kernel + l2_loss_circle # This func derives the equivalent kernel and bias in a DIFFERENTIABLE way. # You can get the equivalent kernel and bias at any time and do whatever you want, # for example, apply some penalties or constraints during training, just like you do to the other models. # May be useful for quantization or pruning. def get_equivalent_kernel_bias(self):#将identity和1*1,3*3融合到一起的参数变化 kernel3x3, bias3x3 = self._fuse_bn_tensor(self.rbr_dense) kernel1x1, bias1x1 = self._fuse_bn_tensor(self.rbr_1x1) kernelid, biasid = self._fuse_bn_tensor(self.rbr_identity) return kernel3x3 + self._pad_1x1_to_3x3_tensor(kernel1x1) + kernelid, bias3x3 + bias1x1 + biasid def _pad_1x1_to_3x3_tensor(self, kernel1x1): if kernel1x1 is None: return 0 else: return torch.nn.functional.pad(kernel1x1, [1,1,1,1]) def _fuse_bn_tensor(self, branch): if branch is None: return 0, 0 if isinstance(branch, nn.Sequential): kernel = branch.conv.weight running_mean = branch.bn.running_mean running_var = branch.bn.running_var gamma = branch.bn.weight beta = branch.bn.bias eps = branch.bn.eps else: assert isinstance(branch, nn.BatchNorm2d) if not hasattr(self, 'id_tensor'): input_dim = self.in_channels // self.groups kernel_value = np.zeros((self.in_channels, input_dim, 3, 3), dtype=np.float32) for i in range(self.in_channels): kernel_value[i, i % input_dim, 1, 1] = 1 self.id_tensor = torch.from_numpy(kernel_value).to(branch.weight.device) kernel = self.id_tensor running_mean = branch.running_mean running_var = branch.running_var gamma = branch.weight beta = branch.bias eps = branch.eps std = (running_var + eps).sqrt() t = (gamma / std).reshape(-1, 1, 1, 1) return kernel * t, beta - running_mean * gamma / std def switch_to_deploy(self):#如何将多分支结构转换为单分支结构 if hasattr(self, 'rbr_reparam'): return kernel, bias = self.get_equivalent_kernel_bias() self.rbr_reparam = nn.Conv2d(in_channels=self.rbr_dense.conv.in_channels, out_channels=self.rbr_dense.conv.out_channels, kernel_size=self.rbr_dense.conv.kernel_size, stride=self.rbr_dense.conv.stride, padding=self.rbr_dense.conv.padding, dilation=self.rbr_dense.conv.dilation, groups=self.rbr_dense.conv.groups, bias=True) self.rbr_reparam.weight.data = kernel self.rbr_reparam.bias.data = bias for para in self.parameters():#消除梯度更新 para.detach_() self.__delattr__('rbr_dense')#删掉没用的分支 self.__delattr__('rbr_1x1') if hasattr(self, 'rbr_identity'): self.__delattr__('rbr_identity') if hasattr(self, 'id_tensor'): self.__delattr__('id_tensor') self.deploy = True class RepVGG(nn.Module): def __init__(self, num_blocks, num_classes, width_multiplier=None, override_groups_map=None, deploy=False, use_se=False): super(RepVGG, self).__init__() assert len(width_multiplier) == 4 self.deploy = deploy self.override_groups_map = override_groups_map or dict() self.use_se = use_se assert 0 not in self.override_groups_map self.in_planes = min(64, int(64 * width_multiplier[0])) self.stage0 = RepVGGBlock(in_channels=3, out_channels=self.in_planes, kernel_size=3, stride=2, padding=1, deploy=self.deploy, use_se=self.use_se) self.cur_layer_idx = 1 self.stage1 = self._make_stage(int(64 * width_multiplier[0]), num_blocks[0], stride=2) self.stage2 = self._make_stage(int(128 * width_multiplier[1]), num_blocks[1], stride=2) self.stage3 = self._make_stage(int(256 * width_multiplier[2]), num_blocks[2], stride=2) self.stage4 = self._make_stage(int(512 * width_multiplier[3]), num_blocks[3], stride=2) self.gap = nn.AdaptiveAvgPool2d(out