/********************************************************************************************************
檔案說明:
        經典LBP特徵的C++程式碼實現
開發環境:
        Win10 + OpenCv2.4.8 + VS2012
時間地點:
        陝西師範大學 2017.3.16
作    者:
        九 月
*********************************************************************************************************/
#include <iostream>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>

using namespace std;
using namespace cv;

cv::Mat OLBP(cv::Mat& srcImg)
{
	const int iRows = srcImg.rows;
	const int iCols = srcImg.cols;

	cv::Mat resultMat(srcImg.size(),srcImg.type());

	//變數影象，生成LBP特徵
	for(int y = 1;y<iRows-1; y++)
	{
		for(int x = 1;x<iCols-1; x++)
		{
			//定義8鄰域
			uchar cNeighbor[8] = {0};
			cNeighbor[0] = srcImg.at<uchar>(y-1,x-1);
			cNeighbor[1] = srcImg.at<uchar>(y-1,x);
			cNeighbor[2] = srcImg.at<uchar>(y-1,x+1);
			cNeighbor[3] = srcImg.at<uchar>(y,  x+1);
			cNeighbor[4] = srcImg.at<uchar>(y+1,x+1);
			cNeighbor[5] = srcImg.at<uchar>(y+1,x);
			cNeighbor[6] = srcImg.at<uchar>(y+1,x-1);
			cNeighbor[7] = srcImg.at<uchar>(y  ,x-1);
			//當前影象的中心畫素點
			uchar cCenter = srcImg.at<uchar>(y,x);
			uchar cTemp   = 0;
			//計算LBP的值
			for(int k =0;k<8;k++)
			{
				cTemp += (cNeighbor[k]>=cCenter)*(1<<k);           //將1的二進位制數按位左移k位
			}
			resultMat.at<uchar>(y,x) = cTemp;
		}//for x
	}//for y
	return resultMat;
}
int main()
{
	cv::Mat srcImg = cv::imread(".\\images\\crack.jpeg",0);
	if(srcImg.empty())
	{
		std::cout<<"【NOTICE】NO valid inout image was given,please check the inoput image!"<<std::endl;
		std::system("pause");
		return -1;
	}
	cv::Mat resultMat = OLBP(srcImg);
	cv::imshow("srcImg",srcImg);
	cv::imshow("resultMat",resultMat);
	cv::waitKey(0);
	return 0;
}