OpenCV Sobel 导数

 

#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <stdlib.h>
#include <stdio.h>

using namespace cv;

/** @function main */
int main( int argc, char** argv )
{

  Mat src, src_gray;
  Mat grad;
  char* window_name = "Sobel Demo - Simple Edge Detector";
  int scale = 1;
  int delta = 0;
  int ddepth = CV_16S;

  int c;

  /// 装载图像
  src = imread( argv[1] );

  if( !src.data )
  { return -1; }

  GaussianBlur( src, src, Size(3,3), 0, 0, BORDER_DEFAULT );

  /// 转换为灰度图
  cvtColor( src, src_gray, CV_RGB2GRAY );

  /// 创建显示窗口
  namedWindow( window_name, CV_WINDOW_AUTOSIZE );

  /// 创建 grad_x 和 grad_y 矩阵
  Mat grad_x, grad_y;
  Mat abs_grad_x, abs_grad_y;

  /// 求 X方向梯度
  //Scharr( src_gray, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
  Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
  convertScaleAbs( grad_x, abs_grad_x );

  /// 求Y方向梯度
  //Scharr( src_gray, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
  Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
  convertScaleAbs( grad_y, abs_grad_y );

  /// 合并梯度(近似)
  addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad );

  imshow( window_name, grad );

  waitKey(0);

  return 0;
  }