玩轉OpenCV 4.0（一）：呼叫Dis光流演算法示例

• 呼叫DIS光流的原始碼如下：
• 對應CMakelists如下：

呼叫DIS光流的原始碼如下：

#include "opencv2/core/utility.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/video.hpp"
#include <iostream>
using namespace std;
using namespace cv;
 

static void help()
{
    printf("Usage: dis_optflow <video_file>\n");
}
int main(int argc, char **argv)
{
    VideoCapture cap;
    if (argc < 2)
    {
        help();
        exit(1);
    }
    cap.open(argv[1]);
    if(!cap.isOpened())
    {
        printf("ERROR: Cannot open file %s\n",
 
 argv[1]);
        return -1;
    }
    Mat prevgray, gray, rgb, frame;
    Mat flow, flow_uv[2];
    Mat flow_Farneback;
    Mat flow_uv_Farneback[2];
    Mat mag, ang;
    Mat mag_Farneback, ang_Farneback;
    Mat hsv_split[3], hsv;
    Mat hsv_split_Farneback[3], hsv_Farneback;
    Mat rgb_Farneback;
 



    Ptr<DenseOpticalFlow> algorithm = DISOpticalFlow::create(DISOpticalFlow::PRESET_MEDIUM);

    int idx = 0;
    while(true)
    {
        cap >> frame;
        if (frame.empty())
            break;
        cv::resize(frame,frame,cv::Size(0.8*frame.cols,0.8*frame.rows),0,0,cv::INTER_LINEAR);
        idx++;
        cvtColor(frame, gray, COLOR_BGR2GRAY);
        cv::imshow("orig", frame);

        if (!prevgray.empty())
        {
            /*DISOpticalFlow*/
            /*main function of DISOpticalFlow*/
            algorithm->calc(prevgray, gray, flow);
            split(flow, flow_uv);
            multiply(flow_uv[1], -1, flow_uv[1]);
            cartToPolar(flow_uv[0], flow_uv[1], mag, ang, true);
            normalize(mag, mag, 0, 1, NORM_MINMAX);
            hsv_split[0] = ang;
            hsv_split[1] = mag;
            hsv_split[2] = Mat::ones(ang.size(), ang.type());
            merge(hsv_split, 3, hsv);
            cvtColor(hsv, rgb, COLOR_HSV2BGR);
            cv::Mat rgbU;
            rgb.convertTo(rgbU, CV_8UC3,  255, 0);
            cv::imshow("DISOpticalFlow", rgbU);
            Mat rgbU_b = rgbU.clone();
            Mat split_dis[3];
            split(rgbU_b, split_dis);

            split_dis[2] = prevgray;
            Mat merge_dis;
            merge(split_dis, 3, merge_dis);
            cv::imshow("DISOpticalFlow_mask", merge_dis);
            /*Farneback*/
            cv::calcOpticalFlowFarneback(prevgray, gray, flow_Farneback, 0.5, 3,15, 3, 5, 1.2, 0);

            split(flow_Farneback, flow_uv_Farneback);
            multiply(flow_uv_Farneback[1], -1, flow_uv_Farneback[1]);
            cartToPolar(flow_uv_Farneback[0], flow_uv_Farneback[1], mag_Farneback, ang_Farneback, true);
            normalize(mag_Farneback, mag_Farneback, 0, 1, NORM_MINMAX);
            hsv_split_Farneback[0] = ang_Farneback;
            hsv_split_Farneback[1] = mag_Farneback;
            hsv_split_Farneback[2] = Mat::ones(ang_Farneback.size(), ang_Farneback.type());
            merge(hsv_split_Farneback, 3, hsv_Farneback);
            cvtColor(hsv_Farneback, rgb_Farneback, COLOR_HSV2BGR);
            cv::Mat rgbU_Farneback;
            rgb_Farneback.convertTo(rgbU_Farneback, CV_8UC3,  255, 0);
            cv::imshow("FlowFarneback", rgbU_Farneback);
            Mat rgbU_Farneback_b = rgbU_Farneback.clone();
            Mat split_Fb[3];
            split(rgbU_Farneback_b, split_Fb);
            split_Fb[2] = prevgray;
            Mat merge_Fb;
            merge(split_Fb, 3, merge_Fb);
            cv::imshow("FlowFarneback_mask", merge_Fb);
            cv::waitKey(1);
        }


        std::swap(prevgray, gray);
    }

    return 0;
}

對應CMakelists如下：

cmake_minimum_required(VERSION 3.12)
set(OpenCV_DIR "/home/fang/software/opencv4_install/lib/cmake/opencv4")
project(indemind_opencv_demo)

set(CMAKE_CXX_STANDARD 14)
find_package(OpenCV 4 REQUIRED)
include_directories( ${OpenCV_INCLUDE_DIRS})
add_executable(indemind_opencv_demo main.cpp)
target_link_libraries(indemind_opencv_demo
        ${OpenCV_LIBS}
        )