Question

我正在尝试比较我存储为数组的两个直方图。我是c ++接口（cv :: Mat）的新手，并在OpenCV中计算直方图。

我的代码：

int testArr1[4] = {12, 10, 11, 11};
int testArr2[4] = {12, 0, 11, 0};
cv::Mat M1 = cv::Mat(1,4,CV_8UC1, testArr1);
cv::Mat M2 = cv::Mat(1,4,CV_8UC1, testArr2);

int histSize = 4;
float range[] = {0, 20};
const float* histRange = {range};
bool uniform = true;
bool accumulate = false;
cv::Mat a1_hist, a2_hist;

cv::calcHist(&M1, 1, 0, cv::Mat(), a1_hist, 1, &histSize, &histRange, uniform, accumulate );
cv::calcHist(&M2, 1, 0, cv::Mat(), a2_hist, 1, &histSize, &histRange, uniform, accumulate );

double compar_c = cv::compareHist(a1_hist, a2_hist, CV_COMP_CORREL);
double compar_chi = cv::compareHist(a1_hist, a2_hist, CV_COMP_CHISQR);
double compar_bh = cv::compareHist(a1_hist, a2_hist, CV_COMP_BHATTACHARYYA);
double compar_i = cv::compareHist(a1_hist, a2_hist, CV_COMP_INTERSECT);
cout << "compare(CV_COMP_CORREL): " << compar_c << "\n";
cout << "compare(CV_COMP_CHISQR): " << compar_chi << "\n";
cout << "compare(CV_COMP_BHATTACHARYYA): " << compar_bh << "\n";
cout << "compare(CV_COMP_INTERSECT): " << compar_i << "\n";

结果有点出乎意料：

compare(CV_COMP_CORREL): 1
compare(CV_COMP_CHISQR): 0
compare(CV_COMP_BHATTACHARYYA): 0
compare(CV_COMP_INTERSECT): 4

例如，对于交叉点，我期望像0.5那样。我究竟做错了什么？我可以不将数组放在cv :: mat中吗？或者我选择了错误的直方图“设置”？

Answer 1

问题是你将c整数数组转换为字符矩阵的前4行。构造函数采用char数组，因此无法正确读取值。您的矩阵M1和M2不包含正确的值。

但是如果更改以下行，那么数组的类型与矩阵的类型匹配：

char testArr1[4] = {12, 10, 11, 11};
char testArr2[4] = {12, 0, 11, 0};

我从你的程序中得到以下输出：

compare(CV_COMP_CORREL): 0.57735
compare(CV_COMP_CHISQR): 2.66667
compare(CV_COMP_BHATTACHARYYA): 0.541196
compare(CV_COMP_INTERSECT): 2

结果比较openCV中的Hist

1 个答案: