这几天又在玩树莓派,先是搞了个物联网,又在尝试在树莓派上搞一些简单的神经网络,这次搞得是mlp识别mnist手写数字识别
训练代码在电脑上,cpu就能训练,很快的:
1 import torch 2 import torch.nn as nn 3 import torch.optim as optim 4 from torchvision import datasets, transforms 5 6 # 设置随机种子 7 torch.manual_seed(42) 8 9 # 定义MLP模型 10 class MLP(nn.Module): 11 def __init__(self): 12 super(MLP, self).__init__() 13 self.fc1 = nn.Linear(784, 256) 14 self.fc2 = nn.Linear(256, 128) 15 self.fc3 = nn.Linear(128, 10) 16 17 def forward(self, x): 18 x = x.view(-1, 784) 19 x = torch.relu(self.fc1(x)) 20 x = torch.relu(self.fc2(x)) 21 x = self.fc3(x) 22 return x 23 24 # 加载MNIST数据集 25 transform = transforms.Compose([ 26 transforms.ToTensor(), 27 # transforms.Normalize((0.1307,), (0.3081,)) 28 ]) 29 30 train_dataset = datasets.MNIST(root='./data', train=True, download=True, transform=transform) 31 test_dataset = datasets.MNIST(root='./data', train=False, download=True, transform=transform) 32 33 train_loader = torch.utils.data.DataLoader(train_dataset, batch_size=64, shuffle=True) 34 test_loader = torch.utils.data.DataLoader(test_dataset, batch_size=64, shuffle=False) 35 36 # 创建模型实例 37 model = MLP() 38 39 # 定义损失函数和优化器 40 criterion = nn.CrossEntropyLoss() 41 optimizer = optim.SGD(model.parameters(), lr=0.01, momentum=0.5) 42 43 # 训练模型 44 def train(model, train_loader, optimizer, criterion, epochs): 45 model.train() 46 for epoch in range(1, epochs + 1): 47 for batch_idx, (data, target) in enumerate(train_loader): 48 optimizer.zero_grad() 49 output = model(data) 50 loss = criterion(output, target) 51 loss.backward() 52 optimizer.step() 53 54 if batch_idx % 100 == 0: 55 print('Epoch: {} [{}/{} ({:.0f}%)]\tLoss: {:.6f}'.format( 56 epoch, batch_idx * len(data), len(train_loader.dataset), 57 100. * batch_idx / len(train_loader), loss.item())) 58 59 # 训练模型 60 train(model, train_loader, optimizer, criterion, epochs=5) 61 62 # 保存模型为NumPy格式 63 numpy_model = {} 64 numpy_model['fc1.weight'] = model.fc1.weight.detach().numpy() 65 numpy_model['fc1.bias'] = model.fc1.bias.detach().numpy() 66 numpy_model['fc2.weight'] = model.fc2.weight.detach().numpy() 67 numpy_model['fc2.bias'] = model.fc2.bias.detach().numpy() 68 numpy_model['fc3.weight'] = model.fc3.weight.detach().numpy() 69 numpy_model['fc3.bias'] = model.fc3.bias.detach().numpy() 70 71 # 保存为NumPy格式的数据 72 import numpy as np 73 np.savez('mnist_model.npz', **numpy_model)
然后需要自己倒出一些图片在dataset里:我保存在了mnist_pi文件夹下,“_”后面的是标签,主要是在pc端导出保存到树莓派下
树莓派推理端的代码,需要numpy手动重新搭建网络,然后加载那些保存的矩阵参数,做矩阵乘法和加法
1 import numpy as np 2 import os 3 from PIL import Image 4 5 # 加载模型 6 model_data = np.load('mnist_model.npz') 7 weights1 = model_data['fc1.weight'] 8 biases1 = model_data['fc1.bias'] 9 weights2 = model_data['fc2.weight'] 10 biases2 = model_data['fc2.bias'] 11 weights3 = model_data['fc3.weight'] 12 biases3 = model_data['fc3.bias'] 13 14 # 进行推理 15 def predict(image, weights1, biases1,weights2, biases2,weights3, biases3): 16 image = image.flatten()/255 # 将输入图像展平并进行归一化 17 output = np.dot(weights1, image) + biases1 18 output = np.dot(weights2, output) + biases2 19 output = np.dot(weights3, output) + biases3 20 predicted_class = np.argmax(output) 21 return predicted_class 22 23 24 25 26 folder_path = './mnist_pi' # 替换为图片所在的文件夹路径 27 def infer_images_in_folder(folder_path): 28 for file_name in os.listdir(folder_path): 29 file_path = os.path.join(folder_path, file_name) 30 if os.path.isfile(file_path) and file_name.endswith(('.jpg', '.jpeg', '.png')): 31 image = Image.open(file_path) 32 label = file_name.split(".")[0].split("_")[1] 33 image = np.array(image) 34 print("file_path:",file_path,"img size:",image.shape,"label:",label) 35 predicted_class = predict(image, weights1, biases1,weights2, biases2,weights3, biases3) 36 print('Predicted class:', predicted_class) 37 38 infer_images_in_folder(folder_path)
结果:
效果还不错:
这次内容就到这里了,下次争取做一个卷积的神经网络在树莓派上推理,然后争取做一个目标检测的模型在树莓派上
标签:树莓,numpy,data,train,path,model,推理 From: https://www.cnblogs.com/LiuXinyu12378/p/17443613.html