环境

cmake

cmake版本大于3.0

$ brew install cmake

vscode

LibTorch

实例

训练模型

# -*- coding:utf-8 -*-
# /usr/bin/python
'''
-------------------------------------------------------------------------
   @File Name      :  pytorch_case.py
   @Description    :  pytorch训练模型
   @Run Script     :  python  pytorch_case.py
   @Envs           :  pip install
   @Change Activity:
        1.  2022/6/13  15:41  : build
-------------------------------------------------------------------------
   @CodeStyle      :  standard, simple, readable, maintainable, and portable!
   @Author         :  Yan Erle 13075851954
   @Email          :  [email protected]
   @Copyright      :  "Copyright 2022, Yan Erle"
-------------------------------------------------------------------------
'''
import torch.optim as optim
import torch.nn.functional as F
import torch.nn as nn
import numpy as np
import matplotlib.pyplot as plt
import torch
import torch.onnx
import torchvision
import torchvision.transforms as transforms
device = torch.device("cuda:0" if torch.cuda.is_available() else "cpu")
transform = transforms.Compose(
    [transforms.ToTensor(),
     transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))])

trainset = torchvision.datasets.CIFAR10(root='./data', train=True,
                                        download=True, transform=transform)
trainloader = torch.utils.data.DataLoader(trainset, batch_size=4,
                                          shuffle=True, num_workers=0)

testset = torchvision.datasets.CIFAR10(root='./data', train=False,
                                       download=True, transform=transform)
testloader = torch.utils.data.DataLoader(testset, batch_size=4,
                                         shuffle=False, num_workers=0)

classes = ('plane', 'car', 'bird', 'cat',
           'deer', 'dog', 'frog', 'horse', 'ship', 'truck')

# functions to show an image

def imshow(img):
    img = img / 2 + 0.5     # unnormalize
    npimg = img.numpy()
    plt.imshow(np.transpose(npimg, (1, 2, 0)))
    plt.show()

# get some random training images
dataiter = iter(trainloader)
images, labels = dataiter.next()

print(images.shape)

# show images
imshow(torchvision.utils.make_grid(images))
# print labels
print(' '.join('%5s' % classes[labels[j]] for j in range(4)))

class Net(nn.Module):
    def __init__(self):
        super(Net, self).__init__()
        self.conv1 = nn.Conv2d(3, 6, 3)
        self.pool = nn.MaxPool2d(2, 2)
        self.conv2 = nn.Conv2d(6, 12, 3)
        self.conv3 = nn.Conv2d(12, 32, 3)
        self.fc1 = nn.Linear(32 * 4 * 4, 120)
        self.fc2 = nn.Linear(120, 84)
        self.fc3 = nn.Linear(84, 10)

    def forward(self, x):
        x = self.pool(F.relu(self.conv1(x)))
        x = self.pool(F.relu(self.conv2(x)))
        x = F.relu(self.conv3(x))
        x = x.view(-1, 32 * 4 * 4)
        x = F.relu(self.fc1(x))
        x = F.relu(self.fc2(x))
        x = self.fc3(x)
        return x

net = Net()
net.to(device)

criterion = nn.CrossEntropyLoss()
optimizer = optim.SGD(net.parameters(), lr=0.001, momentum=0.9)

for epoch in range(10):  # loop over the dataset multiple times

    running_loss = 0.0
    for i, data in enumerate(trainloader, 0):
        # get the inputs; data is a list of [inputs, labels]
        inputs, labels = data[0].to(device), data[1].to(device)

        # zero the parameter gradients
        optimizer.zero_grad()

        # forward + backward + optimize
        outputs = net(inputs)

        loss = criterion(outputs, labels)
        loss.backward()
        optimizer.step()

        # print statistics
        running_loss += loss.item()
        if i % 2000 == 1999:    # print every 2000 mini-batches
            print(outputs)
            print('[%d, %5d] loss: %.3f' %
                  (epoch + 1, i + 1, running_loss / 2000))
            running_loss = 0.0

print('Finished Training')

# 保存网络结构和参数  关键部分
# 方法4:保存网络位TORCHSCRIPT
dummy_input = torch.randn(1, 3, 32, 32).to(device)
traced_cell = torch.jit.trace(net, dummy_input)
traced_cell.save("tests.pth")

C++预测

#include <torch/script.h>
#include <iostream>
#include <opencv2/opencv.hpp>
#include <torch/torch.h>

// 有人说调用的顺序有关系,我这好像没啥用~~

int main()
{
    torch::DeviceType device_type;
    if (torch::cuda::is_available()) {
        std::cout << "CUDA available! Predicting on GPU." << std::endl;
        device_type = torch::kCUDA;
    }
    else {
        std::cout << "Predicting on CPU." << std::endl;
        device_type = torch::kCPU;
    }
    torch::Device device(device_type);

    //Init model
    std::string model_pb = "tests.pth";
    auto module = torch::jit::load(model_pb);
    module.to(at::kCUDA);

    auto image = cv::imread("dog.jpg", cv::ImreadModes::IMREAD_COLOR);
    cv::Mat image_transfomed;
    cv::resize(image, image_transfomed, cv::Size(32, 32));

    // convert to tensort
    torch::Tensor tensor_image = torch::from_blob(image_transfomed.data,
        { image_transfomed.rows, image_transfomed.cols,3 }, torch::kByte);
    tensor_image = tensor_image.permute({ 2,0,1 });
    tensor_image = tensor_image.toType(torch::kFloat);
    tensor_image = tensor_image.div(255);
    tensor_image = tensor_image.unsqueeze(0);
    tensor_image = tensor_image.to(at::kCUDA);
    torch::Tensor output = module.forward({ tensor_image }).toTensor();
    auto max_result = output.max(1, true);
    auto max_index = std::get<1>(max_result).item<float>();
    std::cout << output << std::endl;
    //return max_index;
    return 0;

}