opencv Mat 数据 最大值和最小值

由于之前写的一些程序好多都是基于opencv中的Mat类型的，现在，需要对其中的数据求取最大值和最小值。感觉opencv应该有STL中类似的sort函数...后来，google了一下，发现还真的确实有的。

//! finds global minimum and maximum array elements and returns their values and their locationsCV_EXPORTS_W void minMaxLoc(InputArray src, CV_OUT double* minVal,                           CV_OUT double* maxVal=0, CV_OUT Point* minLoc=0,                           CV_OUT Point* maxLoc=0, InputArray mask=noArray());CV_EXPORTS void minMaxIdx(InputArray src, double* minVal, double* maxVal,                          int* minIdx=0, int* maxIdx=0, InputArray mask=noArray());

实现代码如下所示：

#include <iostream>#include <cstdlib>#include <cmath>#include <iomanip>#include <algorithm>#include "opencv2/core/core.hpp"#include "opencv2/highgui/highgui.hpp"#include "opencv2/imgproc/imgproc.hpp"#include "opencv2/contrib/contrib.hpp"using namespace std;using namespace cv;int main(int argc, char* argv[]){#pragma region min_maxfloat Tval = 0.0;float RawData[2][3] = {{4.0,1.0,3.0},{8.0,7.0,9.0}};Mat RawDataMat(2,3,CV_32FC1,RawData);for (int j = 0; j < 2; j++){for (int i = 0; i < 3; i++){//Tval = RawData[j][i];             //No problem !!!Tval = RawDataMat.at<float>(j,i);cout << "(j,i) = "<<j<<","<<i<<"\t"<<Tval<<endl;}}double minv = 0.0, maxv = 0.0;double* minp = &minv;double* maxp = &maxv;minMaxIdx(RawDataMat,minp,maxp);cout << "Mat minv = " << minv << endl;cout << "Mat maxv = " << maxv << endl;#pragma endregionreturn 0;}

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