将ｏｐｅｎｃｖ　稠密光流farnaeback　cuda 　接口　简答记录一下

#include <iostream>
#include <vector>
#include <sstream>
#include <cmath>#include "opencv2/core.hpp"
#include "opencv2/core/utility.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/video.hpp"
#include "opencv2/cudaoptflow.hpp"
#include "opencv2/cudaarithm.hpp"using namespace std;
using namespace cv;
using namespace cv::cuda;template <typename T>
inline T mapVal(T x, T a, T b, T c, T d)
{x = ::max(::min(x, b), a);return c + (d-c) * (x-a) / (b-a);
}static void colorizeFlow(const Mat &u, const Mat &v, Mat &dst)
{double uMin, uMax;cv::minMaxLoc(u, &uMin, &uMax, 0, 0);double vMin, vMax;cv::minMaxLoc(v, &vMin, &vMax, 0, 0);uMin = ::abs(uMin); uMax = ::abs(uMax);vMin = ::abs(vMin); vMax = ::abs(vMax);float dMax = static_cast<float>(std::max(std::max(uMin, uMax), std::max(vMin, vMax)));dst.create(u.size(), CV_8UC3);for (int y = 0; y < u.rows; ++y){for (int x = 0; x < u.cols; ++x){dst.at<uchar>(y,3*x) = 0;dst.at<uchar>(y,3*x+1) = (uchar)mapVal(-v.at<float>(y,x), -dMax, dMax, 0.f, 255.f);dst.at<uchar>(y,3*x+2) = (uchar)mapVal(u.at<float>(y,x), -dMax, dMax, 0.f, 255.f);}}
}int main(int argc, char **argv)
{const std::string rtsp_or_video_addr="/home/wang/images/drums10.mp4";cv::VideoCapture cap(rtsp_or_video_addr);if(!cap.isOpened()){std::cout<<"frame capture failed!\n";return -1;}Mat frame;Mat curGray,prevGray;namedWindow("flow",WINDOW_NORMAL);Ptr<cuda::FarnebackOpticalFlow> d_calc = cuda::FarnebackOpticalFlow::create();cv::Mat flowx, flowy, image;bool running=true;while (running){cap>>frame;cvtColor(frame,curGray,COLOR_BGR2GRAY);if(!prevGray.empty()){GpuMat gpuPrevFrame(prevGray);GpuMat gpuCurFrame(curGray);GpuMat flowMat;d_calc->calc(gpuPrevFrame, gpuCurFrame, flowMat);GpuMat planes[2];cuda::split(flowMat, planes);planes[0].download(flowx);planes[1].download(flowy);colorizeFlow(flowx, flowy, image);//motionToColor(image,image);cv::imshow("flow", image);cv::waitKey(3);}std::swap(prevGray,curGray);}return 0;
}

配置文件：

QT -= guiCONFIG += c++11 console
CONFIG -= app_bundle# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0SOURCES += \main.cpp
INCLUDEPATH += /usr/local/include\/usr/local/include/opencv\/usr/local/include/opencv2\LIBS +=/usr/local/lib/libopencv_*.so\/usr/local/cuda-9.0/lib64/libcudart.so.9.0\/usr/local/cuda-9.0/lib64/libcudnn.so.7\/usr/local/cuda-9.0/lib64/libcurand.so.9.0\/usr/local/cuda-9.0/lib64/libcublas.so.9.0