程式語言 - OpenCV - C/C++ - Image Processing - Shape Distance

參考資訊：
https://docs.opencv.org/master/d7/d9f/tutorial_linux_install.html

main.cpp

#include <opencv2/shape.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/core/utility.hpp>
#include <iostream>
#include <string>

using namespace std;
using namespace cv;

static vector<Point> simpleContour(const Mat &currentQuery, int n = 300)
{
    vector<vector<Point> > _contoursQuery;
    vector<Point> contoursQuery;

    findContours(currentQuery, _contoursQuery, RETR_LIST, CHAIN_APPROX_NONE);
    for (size_t border = 0; border < _contoursQuery.size(); border++) {
        for (size_t p = 0; p < _contoursQuery[border].size(); p++) {
            contoursQuery.push_back(_contoursQuery[border][p]);
        }
    }

    int dummy = 0;
    for (int add = (int)contoursQuery.size() - 1; add < n; add++) {
        contoursQuery.push_back(contoursQuery[dummy++]);
    }
    cv::randShuffle(contoursQuery);
    vector<Point> cont;
    for (int i = 0; i < n; i++) {
        cont.push_back(contoursQuery[i]);
    }

    return cont;
}

int main(int argc, char **argv)
{
    Size size(300, 300);

    Mat src = imread("1.jpg", IMREAD_GRAYSCALE);
    Mat srcToShow;
    resize(src, srcToShow, size, 0, 0, INTER_LINEAR_EXACT);
    imshow("src", srcToShow);
    moveWindow("src", 0, 300);
    vector<Point> csrc = simpleContour(src);
    if (src.empty()) {
        printf("failed to load 1.jpg\n");
        return -1;
    }

    Mat dst = imread("2.jpg", IMREAD_GRAYSCALE);
    Mat dstToShow;
    resize(dst, dstToShow, size, 0, 0, INTER_LINEAR_EXACT);
    imshow("dst", dstToShow);
    moveWindow("dst", 305, 300);
    vector<Point> cdst = simpleContour(dst);
    if (dst.empty()) {
        printf("failed to load 2.jpg\n");
        return -1;
    }

    cv::Ptr<cv::ShapeContextDistanceExtractor> mysc = cv::createShapeContextDistanceExtractor();
    float dis = mysc->computeDistance(csrc, cdst);
    printf("distance: %f\n", dis);
    waitKey();
    destroyWindow("src");
    destroyWindow("dst");
    return 0;
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)
project(main)
find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})
add_executable(main main.cpp)
target_link_libraries(main ${OpenCV_LIBS})

編譯、執行

$ cmake .
$ make
$ ./main

完成

Distance: 0.139355