#include<iostream>
#include<opencv2\opencv.hpp>
#include<opencv2\highgui\highgui.hpp>
#include<opencv2\imgproc\imgproc.hpp>

int main()
{
  //打开要识别字符的图像
  IplImage *image = cvLoadImage("../../hello.png");
  if (image == NULL)
  {
    std::cout << "错误：无法打开该图像文件！" << std::endl;
  }
  //转换到灰度图像
  IplImage *img_gray = cvCreateImage(cvGetSize(image), image->depth, 1);
  cvCvtColor(image, img_gray, CV_BGR2GRAY);
  //二值化
  IplImage *img_value = cvCreateImage(cvGetSize(img_gray), image->depth, 1);
  cvThreshold(img_gray, img_value, 100, 255, CV_THRESH_BINARY_INV);
  //寻找轮廓
  CvMemStorage *pStorage = cvCreateMemStorage(0);
  CvSeq *pConInner = NULL;
  int num = cvFindContours(img_value, pStorage, &pConInner, sizeof(CvContour),
    CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE);
  //根据轮廓坐标使用方框标出来
  for (int i = 0; i < num; i++)
  {

    CvRect rc = cvBoundingRect(pConInner);
    cvDrawRect(image, cvPoint(rc.x, rc.y), cvPoint(rc.x + rc.width, rc.y + rc.height), CV_RGB(255, 0, 0));
    pConInner = pConInner->h_next;
  }
  //显示图像
  cvNamedWindow("image", 0);
  cvNamedWindow("image_gray", 0);
  cvNamedWindow("img_value", 0);
  cvShowImage("image", image);
  cvShowImage("image_gray", img_gray);
  cvShowImage("img_value", img_value);
  cvWaitKey(0);
}

opencv轮廓提取_二值化