文章目录

• • • • 一、模型转换 onnx2trt
      • 二、配置环境变量
      • 三、调用推理
      • • python示例代码
        • C++ 代码示例

一、模型转换 onnx2trt

方法1：使用wang-xinyu/tensorrtx部署yolov5方法：https://wangsp.blog.csdn.net/article/details/121718501
方法2：使用tensorRT转成engine
方法3：使用C++ onnx_tensorrt将onnx转为trt 的推理engine 参考 【python 方法参考】
方法4：直接使用TensorRT部署onnx【参考】

1. 使用TensorRT部署pytorch模型（c++推理）【参考】
2. TensorRT-pytorch权重文件转engine【参考】
3. pth->onnx->下载好TensorRT库, 进入~/samples/trtexec, 运行make，生成.engine->python run engine 【参考】 【参考2】

使用 trtexec工具转engine
使用 ./trtexec --help 查看命令：

#生成静态batchsize的engine
./trtexec 	--onnx= \ 						#指定onnx模型文件--explicitBatch \ 							#在构建引擎时使用显式批大小(默认=隐式)显示批处理--saveEngine= \ 		#输出engine--workspace= \ 			#设置工作空间大小单位是MB(默认为16MB)--fp16 										#除了fp32之外，还启用fp16精度(默认=禁用)#生成动态batchsize的engine
./trtexec 	--onnx= \						#指定onnx模型文件--minShapes=input: \ 	#最小的NCHW--optShapes=input: \  	#最佳输入维度，跟maxShapes一样就好--maxShapes=input: \ 	#最大输入维度--workspace= \ 			#设置工作空间大小单位是MB(默认为16MB)--saveEngine= \   				#输出engine--fp16   									#除了fp32之外，还启用fp16精度(默认=禁用)#小尺寸的图片可以多batchsize即8x3x416x416
/home/zxl/TensorRT-7.2.3.4/bin/trtexec  --onnx=yolov4_-1_3_416_416_dynamic.onnx \--minShapes=input:1x3x416x416 \--optShapes=input:8x3x416x416 \--maxShapes=input:8x3x416x416 \--workspace=4096 \--saveEngine=yolov4_-1_3_416_416_dynamic_b8_fp16.engine \--fp16#由于内存不够了所以改成4x3x608x608
/home/zxl/TensorRT-7.2.3.4/bin/trtexec  --onnx=yolov4_-1_3_608_608_dynamic.onnx \--minShapes=input:1x3x608x608 \--optShapes=input:4x3x608x608 \--maxShapes=input:4x3x608x608 \--workspace=4096 \--saveEngine=yolov4_-1_3_608_608_dynamic_b4_fp16.engine \--fp16           

测试，执行：

二、配置环境变量

################ TenorRT 包含目录 ######################
C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v11.0\include;
D:\opencv_build\install\include;D:\opencv_build\install\include\opencv2;
D:\Downloads\cuda_cudnn_TensorRT8\TensorRT-8.2.5.1.Windows10.x86_64.cuda-11.4.cudnn8.2\TensorRT-8.2.5.1\samples\common####################  TenorRT 库目录 ############################
D:\opencv_build\install\x64\vc16\lib\*.lib
C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v11.0\lib\x64\*.lib

三、调用推理

使用pycuda【下载】地址。模型训练代码来自 https://github.com/bubbliiiing
安装pycuda 对应python的版本：pycuda-2020.1+cuda101-cp38-cp38-win_amd64.whl
安装tensorrt对应python的版本：tensorrt-8.2.5.1-cp38-none-win_amd64.whl（来自TensorRT-8.2.5.1.Windows10.x86_64.cuda-11.4.cudnn8.2\TensorRT-8.2.5.1\python目录下）

TensorRT调用步骤

1. 创建IBuilder的指针builder
2. 设置推理的显存大小
3. 设置推理的模式，float或者int
4. 利用builder创建ICudaEngine的实例engine
5. 由engine创建上下文context
6. 利用context进行推理，得到结果
7. 释放显存空间

python示例代码

# --*-- coding:utf-8 --*--
import pycuda.autoinit
import pycuda.driver as cuda
import tensorrt as trt
import torch
import time
from PIL import Image
import cv2, os
import torchvision
import numpy as npfilename = '/home/img.png'
max_batch_size = 1
onnx_model_path = "./resnet18.onnx"
TRT_LOGGER = trt.Logger(trt.Logger.WARNING)def get_img_np_nchw(filename):image = cv2.imread(filename)image_cv = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)image_cv = cv2.resize(image_cv, (224, 224))miu = np.array([0.485, 0.456, 0.406]).reshape(3, 1, 1)std = np.array([0.229, 0.224, 0.225]).reshape(3, 1, 1)img_np = np.array(image_cv, dtype=np.float) / 255.img_np = img_np.transpose((2, 0, 1))img_np -= miuimg_np /= stdimg_np_nchw = img_np[np.newaxis]img_np_nchw = np.tile(img_np_nchw, (max_batch_size, 1, 1, 1))return img_np_nchwclass HostDeviceMem(object):def __init__(self, host_mem, device_mem):"""host_mem: cpu memorydevice_mem: gpu memory"""self.host = host_memself.device = device_memdef __str__(self):return "Host:\n" + str(self.host) + "\nDevice:\n" + str(self.device)def __repr__(self):return self.__str__()def allocate_buffers(engine):inputs, outputs, bindings = [], [], []stream = cuda.Stream()for binding in engine:# print(binding) # 绑定的输入输出# print(engine.get_binding_shape(binding)) # get_binding_shape 是变量的大小size = trt.volume(engine.get_binding_shape(binding)) * engine.max_batch_size# volume 计算可迭代变量的空间，指元素个数# size = trt.volume(engine.get_binding_shape(binding)) # 如果采用固定bs的onnx，则采用该句dtype = trt.nptype(engine.get_binding_dtype(binding))# get_binding_dtype  获得binding的数据类型# nptype等价于numpy中的dtype，即数据类型# allocate host and device buffershost_mem = cuda.pagelocked_empty(size, dtype)  # 创建锁业内存device_mem = cuda.mem_alloc(host_mem.nbytes)  # cuda分配空间# print(int(device_mem)) # binding在计算图中的缓冲地址bindings.append(int(device_mem))# append to the appropriate listif engine.binding_is_input(binding):inputs.append(HostDeviceMem(host_mem, device_mem))else:outputs.append(HostDeviceMem(host_mem, device_mem))return inputs, outputs, bindings, streamdef get_engine(max_batch_size=1, onnx_file_path="", engine_file_path="", fp16_mode=False, save_engine=False):"""params max_batch_size:      预先指定大小好分配显存params onnx_file_path:      onnx文件路径params engine_file_path:    待保存的序列化的引擎文件路径params fp16_mode:           是否采用FP16params save_engine:         是否保存引擎returns:                    ICudaEngine"""# 如果已经存在序列化之后的引擎，则直接反序列化得到cudaEngineif os.path.exists(engine_file_path):print("Reading engine from file: {}".format(engine_file_path))with open(engine_file_path, 'rb') as f, \trt.Runtime(TRT_LOGGER) as runtime:return runtime.deserialize_cuda_engine(f.read())  # 反序列化else:  # 由onnx创建cudaEngine# 使用logger创建一个builder# builder创建一个计算图 INetworkDefinitionexplicit_batch = 1 << (int)(trt.NetworkDefinitionCreationFlag.EXPLICIT_BATCH)# In TensorRT 7.0, the ONNX parser only supports full-dimensions mode, meaning that your network definition must be created with the explicitBatch flag set. For more information, see Working With Dynamic Shapes.with trt.Builder(TRT_LOGGER) as builder, \builder.create_network(explicit_batch) as network, \trt.OnnxParser(network, TRT_LOGGER) as parser:  # 使用onnx的解析器绑定计算图，后续将通过解析填充计算图builder.max_workspace_size = 1 << 30  # 预先分配的工作空间大小,即ICudaEngine执行时GPU最大需要的空间builder.max_batch_size = max_batch_size  # 执行时最大可以使用的batchsizebuilder.fp16_mode = fp16_mode# 解析onnx文件，填充计算图if not os.path.exists(onnx_file_path):quit("ONNX file {} not found!".format(onnx_file_path))print('loading onnx file from path {} ...'.format(onnx_file_path))with open(onnx_file_path, 'rb') as model:  # 二值化的网络结果和参数print("Begining onnx file parsing")parser.parse(model.read())  # 解析onnx文件# parser.parse_from_file(onnx_file_path) # parser还有一个从文件解析onnx的方法print("Completed parsing of onnx file")# 填充计算图完成后，则使用builder从计算图中创建CudaEngineprint("Building an engine from file{}' this may take a while...".format(onnx_file_path))#################print(network.get_layer(network.num_layers - 1).get_output(0).shape)# network.mark_output(network.get_layer(network.num_layers -1).get_output(0))engine = builder.build_cuda_engine(network)  # 注意，这里的network是INetworkDefinition类型，即填充后的计算图print("Completed creating Engine")if save_engine:  # 保存engine供以后直接反序列化使用with open(engine_file_path, 'wb') as f:f.write(engine.serialize())  # 序列化return enginedef do_inference(context, bindings, inputs, outputs, stream, batch_size=1):# Transfer data from CPU to the GPU.[cuda.memcpy_htod_async(inp.device, inp.host, stream) for inp in inputs]# htod： host to device 将数据由cpu复制到gpu device# Run inference.context.execute_async_v2(bindings=bindings, stream_handle=stream.handle)# 当创建network时显式指定了batchsize， 则使用execute_async_v2, 否则使用execute_async# Transfer predictions back from the GPU.[cuda.memcpy_dtoh_async(out.host, out.device, stream) for out in outputs]# gpu to cpu# Synchronize the streamstream.synchronize()# Return only the host outputs.return [out.host for out in outputs]def postprocess_the_outputs(h_outputs, shape_of_output):h_outputs = h_outputs.reshape(*shape_of_output)return h_outputsimg_np_nchw = get_img_np_nchw(filename).astype(np.float32)
# These two modes are depend on hardwares
fp16_mode = False
trt_engine_path = "./model_fp16_{}.trt".format(fp16_mode)
# Build an cudaEngine
engine = get_engine(max_batch_size, onnx_model_path, trt_engine_path, fp16_mode)
# 创建CudaEngine之后,需要将该引擎应用到不同的卡上配置执行环境
context = engine.create_execution_context()
inputs, outputs, bindings, stream = allocate_buffers(engine)  # input, output: host # bindings# Do inference
shape_of_output = (max_batch_size, 1000)
# Load data to the buffer
inputs[0].host = img_np_nchw.reshape(-1)# inputs[1].host = ... for multiple input
t1 = time.time()
trt_outputs = do_inference(context, bindings=bindings, inputs=inputs, outputs=outputs, stream=stream)  # numpy data
t2 = time.time()
feat = postprocess_the_outputs(trt_outputs[0], shape_of_output)print('TensorRT ok')model = torchvision.models.resnet18(pretrained=True).cuda()
resnet_model = model.eval()
input_for_torch = torch.from_numpy(img_np_nchw).cuda()
t3 = time.time()
feat_2 = resnet_model(input_for_torch)
t4 = time.time()
feat_2 = feat_2.cpu().data.numpy()
print('Pytorch ok!')mse = np.mean((feat - feat_2) ** 2)
print("Inference time with the TensorRT engine: {}".format(t2 - t1))
print("Inference time with the PyTorch model: {}".format(t4 - t3))
print('MSE Error = {}'.format(mse))print('All completed!')

C++ 代码示例

TensorRT 傻瓜式部署流程：参考

#include #include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "NvInfer.h"
#include "NvOnnxParser.h"
#include "argsParser.h"
#include "logger.h"
#include "common.h"#ifndef NOMINMAX
#ifndef max_idx
#define max_idx(a,b)            (((a) > (b)) ? (0) : (1))
#endif
#endif /* NOMINMAX */
#define DebugP(x) std::cout << "Line" << __LINE__ << "  " << #x << "=" << x << std::endlusing namespace nvinfer1;
samplesCommon::Args gArgs;
using namespace sample;static const int INPUT_H = 480;
static const int INPUT_W = 480;
static const int INPUT_C = 3;
static constexpr int  INPUT_SIZE = INPUT_H * INPUT_W * 3;
static constexpr int OUTPUT_SIZE = INPUT_H * INPUT_W * 2;
static const cv::Size newShape = cv::Size(INPUT_W, INPUT_H);const std::string trtModelName = "D:\\xxx.engine";
const std::string onnxModeName = "D:\\xxx.onnx";
const std::string file_name = "D:\\xxx.jpg";struct TensorRT {IExecutionContext* context;ICudaEngine* engine;IRuntime* runtime;
};void image_to_center(const cv::Mat& image, cv::Mat& outImage, cv::Mat& IM, const cv::Scalar& color)
{cv::Size shape = image.size();float scale_xy = std::min((float)newShape.height / (float)shape.height,(float)newShape.width / (float)shape.width);cv::Mat M = (cv::Mat_(2, 3) <cv::warpAffine(image, outImage, IM, newShape);
}void normal_image2blob(float* blob, cv::Mat& img) {for (int c = 0; c < 3; ++c) {for (int i = 0; i < img.rows; ++i) {cv::Vec3b* p1 = img.ptr(i);for (int j = 0; j < img.cols; ++j) {blob[c * img.cols * img.rows + i * img.cols + j] = p1[j][c] * 0.00392156862745098;}}}
}bool onnxToTRTModel(const std::string& modelFile, // name of the onnx modelunsigned int maxBatchSize,                    // batch size - NB must be at least as large as the batch we want to run withIHostMemory*& trtModelStream)                 // output buffer for the TensorRT model
{// create the builderIBuilder* builder = createInferBuilder(gLogger.getTRTLogger());assert(builder != nullptr);nvinfer1::INetworkDefinition* network = builder->createNetworkV2(maxBatchSize);nvinfer1::IBuilderConfig* config = builder->createBuilderConfig();config->setMaxWorkspaceSize(1 << 20);// parserauto parser = nvonnxparser::createParser(*network, gLogger.getTRTLogger());if (!parser->parseFromFile(modelFile.c_str(), static_cast(gLogger.getReportableSeverity()))){gLogError << "Failure while parsing ONNX file" << std::endl;return false;}if (builder->platformHasFastFp16()) {config->setFlag(nvinfer1::BuilderFlag::kFP16);}else {std::cout << "This platform does not support fp16" << std::endl;}// Build the engineICudaEngine* engine = builder->buildEngineWithConfig(*network, *config);assert(engine);// serialize the engine, then close everything downtrtModelStream = engine->serialize();parser->destroy();engine->destroy();network->destroy();builder->destroy();std::ofstream ofs(trtModelName.c_str(), std::ios::out | std::ios::binary);ofs.write((char*)(trtModelStream->data()), trtModelStream->size());ofs.close();DebugP("Trt model save success!");return true;
}TensorRT* LoadNet(const char* trtFileName)
{std::ifstream t(trtFileName, std::ios::in | std::ios::binary);std::stringstream tempStream;tempStream << t.rdbuf();t.close();DebugP("TRT File Loaded successfully!");tempStream.seekg(0, std::ios::end);const int modelSize = tempStream.tellg();tempStream.seekg(0, std::ios::beg);void* modelMem = malloc(modelSize);tempStream.read((char*)modelMem, modelSize);IRuntime* runtime = createInferRuntime(gLogger);if (runtime == nullptr){DebugP("Build Runtime Failure");return 0;}if (gArgs.useDLACore >= 0){runtime->setDLACore(gArgs.useDLACore);}ICudaEngine* engine = runtime->deserializeCudaEngine(modelMem, modelSize, nullptr);if (engine == nullptr){DebugP("Build Engine Failure");return 0;}IExecutionContext* context = engine->createExecutionContext();if (context == nullptr){DebugP("Build Context Failure");return 0;}TensorRT* trt = new TensorRT();trt->context = context;trt->engine = engine;trt->runtime = runtime;DebugP("Build trt Model Success!");return trt;
}void doInference(IExecutionContext& context, float* input, float* output, int batchSize)
{const ICudaEngine& engine = context.getEngine();assert(engine.getNbBindings() == 2);void* buffers[2];int inputIndex, outputIndex;for (int b = 0; b < engine.getNbBindings(); ++b){if (engine.bindingIsInput(b))inputIndex = b;elseoutputIndex = b;}std::cout << "inputIndex=" << inputIndex << "\n";std::cout << "outputIndex=" << outputIndex << "\n";// create GPU buffers and a streamCHECK(cudaMalloc(&buffers[inputIndex], batchSize * INPUT_C * INPUT_H * INPUT_W * sizeof(float)));CHECK(cudaMalloc(&buffers[outputIndex], batchSize * OUTPUT_SIZE * sizeof(float)));cudaStream_t stream;CHECK(cudaStreamCreate(&stream));// DMA the input to the GPU,  execute the batch asynchronously, and DMA it back:CHECK(cudaMemcpyAsync(buffers[inputIndex], input, batchSize * INPUT_C * INPUT_H * INPUT_W * sizeof(float), cudaMemcpyHostToDevice, stream));context.enqueue(batchSize, buffers, stream, nullptr);CHECK(cudaMemcpyAsync(output, buffers[outputIndex], batchSize * OUTPUT_SIZE * sizeof(float), cudaMemcpyDeviceToHost, stream));cudaStreamSynchronize(stream);// release the stream and the bufferscudaStreamDestroy(stream);CHECK(cudaFree(buffers[inputIndex]));CHECK(cudaFree(buffers[outputIndex]));
}void PostProcessing(float* out, cv::Mat& image_clone, cv::Mat& IM, cv::Size& rawShape)
{uchar colors[2][3] = { {0,0,0},{128,0,0} };constexpr int single_len = INPUT_W * INPUT_H;cv::Mat mask_mat = cv::Mat::zeros(INPUT_W, INPUT_H, CV_8UC3);float src[2] = { 0 };uchar color_idx = 0;for (size_t i = 0; i < INPUT_H; i++) {uchar* mask_ptr = mask_mat.ptr(i);for (size_t j = 0; j < INPUT_W; j++) {color_idx = max_idx(out[i * INPUT_W + j], out[single_len + i * INPUT_W + j]);*mask_ptr++ = colors[color_idx][2];*mask_ptr++ = colors[color_idx][1];*mask_ptr++ = colors[color_idx][0];}}//cv::imwrite("../mask_mat.png", mask_mat);//cv::warpAffine(mask_mat, mask_mat, IM, rawShape);//cv::addWeighted(image_clone, 0.6, mask_mat, 0.4, 0, image_clone);//cv::imwrite("../image_clone.png", image_clone);
}int main(int argc, char** argv)
{IHostMemory* trtModelStream{ nullptr };TensorRT* ptensor_rt;IExecutionContext* context = nullptr;IRuntime* runtime = nullptr;ICudaEngine* engine = nullptr;if (_access(trtModelName.c_str(), 0) != 1){ptensor_rt = LoadNet(trtModelName.c_str());context = ptensor_rt->context;runtime = ptensor_rt->runtime;engine = ptensor_rt->engine;}else{if (!onnxToTRTModel(onnxModeName, 1, trtModelStream))return 1;assert(trtModelStream != nullptr);std::cout << "Successfully parsed ONNX file!!!!" << std::endl;// deserialize the engineruntime = createInferRuntime(gLogger);assert(runtime != nullptr);if (gArgs.useDLACore >= 0){runtime->setDLACore(gArgs.useDLACore);}engine = runtime->deserializeCudaEngine(trtModelStream->data(), trtModelStream->size(), nullptr);assert(engine != nullptr);trtModelStream->destroy();context = engine->createExecutionContext();assert(context != nullptr);}// 输入预处理std::cout << "Start reading the input image!!!!" << std::endl;cv::Mat image = cv::imread(file_name, cv::IMREAD_COLOR);cv::cvtColor(image, image, cv::COLOR_BGR2RGB);cv::Mat image_clone = image.clone();cv::Size rawShape = image.size();// 图像转成blobcv::Mat outImage, IM;image_to_center(image, outImage, IM, cv::Scalar(128, 128, 128));float* blob = new float[INPUT_SIZE] { 0 };normal_image2blob(blob, outImage);float* out = new float[OUTPUT_SIZE] { 0 };// 推理计时typedef std::chrono::high_resolution_clock Time;typedef std::chrono::duration> ms;typedef std::chrono::duration fsec;double total = 0.0;auto t0 = Time::now();doInference(*context, blob, out, 1);auto t1 = Time::now();fsec fs = t1 - t0;ms d = std::chrono::duration_cast(fs);total += d.count();// 网络输出的后处理PostProcessing(out, image_clone,IM, rawShape);// 释放缓存context->destroy();engine->destroy();runtime->destroy();if (blob){delete[] blob;}if (out){delete[] out;}std::cout << std::endl << "Running time of one image is:" << total << "ms" << std::endl;return 0;
}

编译添加预处理：_CRT_SECURE_NO_WARNINGS