阈值bar

#include "stdafx.h"
#include <opencv2/opencv.hpp>
using namespace std;

#pragma comment(linker, "/subsystem:"windows" /entry:"mainCRTStartup"")

IplImage *g_pGrayImage = NULL;
IplImage *g_pBinaryImage = NULL;
const char *pstrWindowsBinaryTitle = "二值图(http://blog.csdn.net/MoreWindows)";

void on_trackbar(int pos)
{
// 转为二值图
cvThreshold(g_pGrayImage, g_pBinaryImage, pos, 255, CV_THRESH_BINARY);
// 显示二值图
cvShowImage(pstrWindowsBinaryTitle, g_pBinaryImage);
}

int main(int argc, char** argv)
{
const char *pstrWindowsSrcTitle = "原图(http://blog.csdn.net/MoreWindows)";
const char *pstrWindowsToolBarName = "二值图阈值";

// 从文件中加载原图
IplImage *pSrcImage = cvLoadImage("E://test1.png", CV_LOAD_IMAGE_UNCHANGED);

// 转为灰度图
g_pGrayImage = cvCreateImage(cvGetSize(pSrcImage), IPL_DEPTH_8U, 1);
cvCvtColor(pSrcImage, g_pGrayImage, CV_BGR2GRAY);

// 创建二值图
g_pBinaryImage = cvCreateImage(cvGetSize(g_pGrayImage), IPL_DEPTH_8U, 1);

// 显示原图
cvNamedWindow(pstrWindowsSrcTitle, CV_WINDOW_AUTOSIZE);
cvShowImage(pstrWindowsSrcTitle, pSrcImage);
// 创建二值图窗口
cvNamedWindow(pstrWindowsBinaryTitle, CV_WINDOW_AUTOSIZE);

// 滑动条
int nThreshold = 0;
cvCreateTrackbar(pstrWindowsToolBarName, pstrWindowsBinaryTitle, &nThreshold, 254, on_trackbar);

on_trackbar(1);

cvWaitKey(0);

cvDestroyWindow(pstrWindowsSrcTitle);
cvDestroyWindow(pstrWindowsBinaryTitle);
cvReleaseImage(&pSrcImage);
cvReleaseImage(&g_pGrayImage);
cvReleaseImage(&g_pBinaryImage);
return 0;
}