[人工智能]win10+libtorch+yolov5-6.0部署

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前言

Libtorch是pytorch的C++版本，现在的很多大型项目都是用C++写的，想使用训练好的模型，需要通过caffe等方式去集成，比较麻烦。 这里pytorch官方提出了Libtorch，我们就可以把pytorch训练好的模型，打包起来，直接在C++工程中去用就好了，相比较caffe等，非常方便！

提示：以下是本篇文章正文内容，下面案例可供参考

一、环境配置

本机配置：cuda11.1、pytorch1.8.2、cudnn8.2、vs2019、opencv4.5.3

环境下载

vs2019下载链接：下载vs2019
opencv下载链接：下载opencv
libtorch下载链接：下载libtorch
cuda和cudnn下载链接：下载cuda11.1.1下载cudnn8.2
安装pytorch

安装libtorch，下载放到文件里即可

安装成功

测试代码，在vs2019中新建工程、空项目。

#include "torch/torch.h"
#include "torch/script.h"

int main()
{
    torch::Tensor output = torch::randn({ 3,2 });
    std::cout << output;

    return 0;
}

二、环境变量的配置

参考博文
1。打开项目-配置属性-调试-环境，输入libtorch的地址

PATH=D:\Myproject\libtorch-win-shared-with-deps-1.8.1+cu111\libtorch\lib;%CUDA_PATH%;%PATH%$(LocalDebuggerEnvironment)

2。更改VC++目录-包含目录

更改外部包含目录

更改库目录，添加opencv、libtorch、cuda地址

3.更改C/C++ - 常规-附加包含目录

语言-符合模式改为否

3。更改链接器-常规-附加库目录

更改输入-附加依赖项

c10.lib
caffe2_nvrtc.lib
c10_cuda.lib
torch.lib
torch_cuda.lib
torch_cuda_cu.lib
-INCLUDE:?searchsorted_cuda@native@at@@YA?AVTensor@2@AEBV32@0_N1@Z
torch_cuda_cpp.lib
torch_cpu.lib
cublas.lib
cudnn.lib
opencv_world340.lib
opencv_world340d.lib
-INCLUDE:?warp_size@cuda@at@@YAHXZ

更改命令行，加入/INCLUDE:?warp_size@cuda@at@@YAHXZ ，否则可能无法调用cuda

三.模型在libtorch上的部署

参考的博文代码：链接我用的是yolov56.0版本，目前还没有试最新的版本。
这里有我在使用orchscript模型时遇到问题需要解决，留一下坑：
问题1.我在使用yolov5官方代码expor.py转换的模型时会出现报错，目前猜测是模型不匹配的结果原因，所以后续是否可以用官方代码进行转换的模型使用？

！！！如果出现module.forward(inputs)C++ 异常: std::runtime_error，位于内存位置的错误就是模型不匹配的结果，

转换模型代码

"""Exports a YOLOv5 *.pt model to ONNX and TorchScript formats

Usage:
    $ export PYTHONPATH="$PWD" && python models/export.py --weights ./weights/yolov5s.pt --img 640 --batch 1
"""

import argparse
import sys
import time

sys.path.append('./')  # to run '$ python *.py' files in subdirectories

import torch
import torch.nn as nn

import models
from models.experimental import attempt_load
from utils.activations import Hardswish, SiLU
from utils.general import set_logging, check_img_size
if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('--weights', type=str, default=r'D:\project_process\Completed_projects\yolo-deploy\yolov5-6.0\weights\yolov5n.pt', help='weights path')  # from yolov5/models/
    parser.add_argument('--img-size', nargs='+', type=int, default=[640, 640], help='image size')  # height, width
    parser.add_argument('--batch-size', type=int, default=1, help='batch size')
    opt = parser.parse_args()
    opt.img_size *= 2 if len(opt.img_size) == 1 else 1  # expand
    print(opt)
    set_logging()
    t = time.time()
    # Load PyTorch model
    model = attempt_load(opt.weights, map_location=torch.device('cuda'))  # load FP32 model
    labels = model.names
    # Checks
    gs = int(max(model.stride))  # grid size (max stride)
    opt.img_size = [check_img_size(x, gs) for x in opt.img_size]  # verify img_size are gs-multiples
    # Input
    img = torch.zeros(opt.batch_size, 3, *opt.img_size).to(device='cuda')
    # image size(1,3,320,192) iDetection
    # Update model
    for k, m in model.named_modules():
        m._non_persistent_buffers_set = set()  # pytorch 1.6.0 compatibility
        if isinstance(m, models.common.Conv):  # assign export-friendly activations
            if isinstance(m.act, nn.Hardswish):
                m.act = Hardswish()
            elif isinstance(m.act, nn.SiLU):
                m.act = SiLU()
        # elif isinstance(m, models.yolo.Detect):
        #     m.forward = m.forward_export  # assign forward (optional)
    #model.model[-1].export = True  # set Detect() layer export=True
    model.model[-1].export = False
    y = model(img)  # dry run
    # TorchScript export
    try:
        print('\nStarting TorchScript export with torch %s...' % torch.__version__)
        f = opt.weights.replace('.pt', '.torchscript.pt')  # filename
        ts = torch.jit.trace(model, img)
        ts.save(f)
        print('TorchScript export success, saved as %s' % f)
    except Exception as e:
        print('TorchScript export failure: %s' % e)
    # ONNX export
    try:
        import onnx
        print('\nStarting ONNX export with onnx %s...' % onnx.__version__)
        f = opt.weights.replace('.pt', '.onnx')  # filename
        torch.onnx.export(model, img, f, verbose=False, opset_version=12, input_names=['images'],
                          output_names=['classes', 'boxes'] if y is None else ['output'])
        # Checks
        onnx_model = onnx.load(f)  # load onnx model
        onnx.checker.check_model(onnx_model)  # check onnx model
        # print(onnx.helper.printable_graph(onnx_model.graph))  # print a human readable model
        print('ONNX export success, saved as %s' % f)
    except Exception as e:
        print('ONNX export failure: %s' % e)
    # CoreML export
    try:
        import coremltools as ct
        print('\nStarting CoreML export with coremltools %s...' % ct.__version__)
        # convert model from torchscript and apply pixel scaling as per detect.py
        model = ct.convert(ts, inputs=[ct.ImageType(name='image', shape=img.shape, scale=1 / 255.0, bias=[0, 0, 0])])
        f = opt.weights.replace('.pt', '.mlmodel')  # filename
        model.save(f)
        print('CoreML export success, saved as %s' % f)
    except Exception as e:
        print('CoreML export failure: %s' % e)
    # Finish
    print('\nExport complete (%.2fs). Visualize with https://github.com/lutzroeder/netron.' % (time.time() - t))

模型推理代码（video）

修改模型进行编译即可，模型文件放在项目main.cpp同一目录下。

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

std::vector<torch::Tensor> non_max_suppression(torch::Tensor preds, float score_thresh = 0.01, float iou_thresh = 0.35)
{
    std::vector<torch::Tensor> output;
    for (size_t i = 0; i < preds.sizes()[0]; ++i)
    {
        torch::Tensor pred = preds.select(0, i);

        //GPU推理结果为cuda数据类型，nms之前要转成cpu，否则会报错
        pred = pred.to(at::kCPU); //增加到函数里pred = pred.to(at::kCPU); 注意preds的数据类型，转成cpu进行后处理。

        // Filter by scores
        torch::Tensor scores = pred.select(1, 4) * std::get<0>(torch::max(pred.slice(1, 5, pred.sizes()[1]), 1));
        pred = torch::index_select(pred, 0, torch::nonzero(scores > score_thresh).select(1, 0));
        if (pred.sizes()[0] == 0) continue;

        // (center_x, center_y, w, h) to (left, top, right, bottom)
        pred.select(1, 0) = pred.select(1, 0) - pred.select(1, 2) / 2;
        pred.select(1, 1) = pred.select(1, 1) - pred.select(1, 3) / 2;
        pred.select(1, 2) = pred.select(1, 0) + pred.select(1, 2);
        pred.select(1, 3) = pred.select(1, 1) + pred.select(1, 3);

        // Computing scores and classes
        std::tuple<torch::Tensor, torch::Tensor> max_tuple = torch::max(pred.slice(1, 5, pred.sizes()[1]), 1);
        pred.select(1, 4) = pred.select(1, 4) * std::get<0>(max_tuple);
        pred.select(1, 5) = std::get<1>(max_tuple);

        torch::Tensor  dets = pred.slice(1, 0, 6);

        torch::Tensor keep = torch::empty({ dets.sizes()[0] });
        torch::Tensor areas = (dets.select(1, 3) - dets.select(1, 1)) * (dets.select(1, 2) - dets.select(1, 0));
        std::tuple<torch::Tensor, torch::Tensor> indexes_tuple = torch::sort(dets.select(1, 4), 0, 1);
        torch::Tensor v = std::get<0>(indexes_tuple);
        torch::Tensor indexes = std::get<1>(indexes_tuple);
        int count = 0;
        while (indexes.sizes()[0] > 0)
        {
            keep[count] = (indexes[0].item().toInt());
            count += 1;

            // Computing overlaps
            torch::Tensor lefts = torch::empty(indexes.sizes()[0] - 1);
            torch::Tensor tops = torch::empty(indexes.sizes()[0] - 1);
            torch::Tensor rights = torch::empty(indexes.sizes()[0] - 1);
            torch::Tensor bottoms = torch::empty(indexes.sizes()[0] - 1);
            torch::Tensor widths = torch::empty(indexes.sizes()[0] - 1);
            torch::Tensor heights = torch::empty(indexes.sizes()[0] - 1);
            for (size_t i = 0; i < indexes.sizes()[0] - 1; ++i)
            {
                lefts[i] = std::max(dets[indexes[0]][0].item().toFloat(), dets[indexes[i + 1]][0].item().toFloat());
                tops[i] = std::max(dets[indexes[0]][1].item().toFloat(), dets[indexes[i + 1]][1].item().toFloat());
                rights[i] = std::min(dets[indexes[0]][2].item().toFloat(), dets[indexes[i + 1]][2].item().toFloat());
                bottoms[i] = std::min(dets[indexes[0]][3].item().toFloat(), dets[indexes[i + 1]][3].item().toFloat());
                widths[i] = std::max(float(0), rights[i].item().toFloat() - lefts[i].item().toFloat());
                heights[i] = std::max(float(0), bottoms[i].item().toFloat() - tops[i].item().toFloat());
            }
            torch::Tensor overlaps = widths * heights;

            // FIlter by IOUs
            torch::Tensor ious = overlaps / (areas.select(0, indexes[0].item().toInt()) + torch::index_select(areas, 0, indexes.slice(0, 1, indexes.sizes()[0])) - overlaps);
            indexes = torch::index_select(indexes, 0, torch::nonzero(ious <= iou_thresh).select(1, 0) + 1);
        }
        keep = keep.toType(torch::kInt64);
        output.push_back(torch::index_select(dets, 0, keep.slice(0, 0, count)));
    }
    return output;
}

#include <torch/script.h> 
#include <iostream>
#include <memory>
//int main(int argc, const char* argv[]) {
//    std::cout << "cuda::is_available():" << torch::cuda::is_available() << std::endl;
//    torch::DeviceType device_type = at::kCPU; // 定义设备类型
//    if (torch::cuda::is_available())
//        device_type = at::kCUDA;
//}


int main(int argc, char* argv[])
{
    std::cout << "cuda::is_available():" << torch::cuda::is_available() << std::endl;
    torch::DeviceType device_type = at::kCPU; // 定义设备类型
    if (torch::cuda::is_available())
        device_type = at::kCUDA;
    // Loading  Module
    torch::jit::script::Module module = torch::jit::load("yolov5n.torchscript.pt");//best.torchscript3.pt//yolov5x.torchscript.pt
    module.to(device_type); // 模型加载至GPU

    std::vector<std::string> classnames;
    std::ifstream f("class.names");
    std::string name = "";
    while (std::getline(f, name))
    {
        classnames.push_back(name);
    }
   
    std::string video = argv[1];
    cv::VideoCapture cap = cv::VideoCapture(video);
    // cap.set(cv::CAP_PROP_FRAME_WIDTH, 1920);
    // cap.set(cv::CAP_PROP_FRAME_HEIGHT, 1080);
    cv::Mat frame, img;
    cap.read(frame);
    int width = frame.size().width;
    int height = frame.size().height;
    int count = 0;
    while (cap.isOpened())
    {
        count++;
        clock_t start = clock();
        cap.read(frame);
        if (frame.empty())
        {
            std::cout << "Read frame failed!" << std::endl;
            break;
        }

        // Preparing input tensor
        cv::resize(frame, img, cv::Size(640, 640));
        // cv::cvtColor(img, img, cv::COLOR_BGR2RGB);
        // torch::Tensor imgTensor = torch::from_blob(img.data, {img.rows, img.cols,3},torch::kByte);
        // imgTensor = imgTensor.permute({2,0,1});
        // imgTensor = imgTensor.toType(torch::kFloat);
        // imgTensor = imgTensor.div(255);
        // imgTensor = imgTensor.unsqueeze(0);
        // imgTensor = imgTensor.to(device_type);
        cv::cvtColor(img, img, cv::COLOR_BGR2RGB);  // BGR -> RGB
        img.convertTo(img, CV_32FC3, 1.0f / 255.0f);  // normalization 1/255
        auto imgTensor = torch::from_blob(img.data, { 1, img.rows, img.cols, img.channels() }).to(device_type);
        imgTensor = imgTensor.permute({ 0, 3, 1, 2 }).contiguous();  // BHWC -> BCHW (Batch, Channel, Height, Width)
        std::vector<torch::jit::IValue> inputs;
        inputs.emplace_back(imgTensor);
        // preds: [?, 15120, 9]
        torch::jit::IValue output = module.forward(inputs);
        auto preds = output.toTuple()->elements()[0].toTensor();
        // torch::Tensor preds = module.forward({ imgTensor }).toTensor();
        std::vector<torch::Tensor> dets = non_max_suppression(preds, 0.35, 0.5);
        if (dets.size() > 0)
        {
            // Visualize result
            for (size_t i = 0; i < dets[0].sizes()[0]; ++i)
            {
                float left = dets[0][i][0].item().toFloat() * frame.cols / 640;
                float top = dets[0][i][1].item().toFloat() * frame.rows / 640;
                float right = dets[0][i][2].item().toFloat() * frame.cols / 640;
                float bottom = dets[0][i][3].item().toFloat() * frame.rows / 640;
                float score = dets[0][i][4].item().toFloat();
                int classID = dets[0][i][5].item().toInt();

                cv::rectangle(frame, cv::Rect(left, top, (right - left), (bottom - top)), cv::Scalar(0, 255, 0), 2);

                cv::putText(frame,
                    classnames[classID] + ": " + cv::format("%.2f", score),
                    cv::Point(left, top),
                    cv::FONT_HERSHEY_SIMPLEX, (right - left) / 200, cv::Scalar(0, 255, 0), 2);
            }
        }
        // std::cout << "-[INFO] Frame:" <<  std::to_string(count) << " FPS: " + std::to_string(float(1e7 / (clock() - start))) << std::endl;
        std::cout << "-[INFO] Frame:" << std::to_string(count) << std::endl;
        // cv::putText(frame, "FPS: " + std::to_string(int(1e7 / (clock() - start))),
        //     cv::Point(50, 50),
        //     cv::FONT_HERSHEY_SIMPLEX, 1, cv::Scalar(0, 255, 0), 2);
        cv::imshow("", frame);
        // cv::imwrite("../images/"+cv::format("%06d", count)+".jpg", frame);
        cv::resize(frame, frame, cv::Size(width, height));
        if (cv::waitKey(1) == 27) break;
    }
    cap.release();
    return 0;
}

点击生成解决方案，会生成一个.exe文件，用cmd运行
运行指令：

Project1.exe "C:\\Users\\11097\\source\\repos\\Project1\\x64\\Release\\test.mp4"

总结

1。需要做到适配yolov5最新的模型版本，6.1版本