OpenCV 图像金字塔

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

using namespace cv;

/// 全局变量
Mat src, dst, tmp;
char* window_name = "Pyramids Demo";


/**
 * @函数 main
 */
int main( int argc, char** argv )
{
  /// 指示说明
  printf( "
 Zoom In-Out demo  
 " );
  printf( "------------------ 
" );
  printf( " * [u] -> Zoom in  
" );
  printf( " * [d] -> Zoom out 
" );
  printf( " * [ESC] -> Close program 
 
" );

  /// 测试图像 - 尺寸必须能被 2^{n} 整除
  src = imread( "../images/chicky_512.jpg" );
  if( !src.data )
    { printf(" No data! -- Exiting the program 
");
      return -1; }

  tmp = src;
  dst = tmp;

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

  /// 循环
  while( true )
  {
    int c;
    c = waitKey(10);

    if( (char)c == 27 )
      { break; }
    if( (char)c == 'u' )
      { pyrUp( tmp, dst, Size( tmp.cols*2, tmp.rows*2 ) );
        printf( "** Zoom In: Image x 2 
" );
      }
    else if( (char)c == 'd' )
     { pyrDown( tmp, dst, Size( tmp.cols/2, tmp.rows/2 ) );
       printf( "** Zoom Out: Image / 2 
" );
     }

    imshow( window_name, dst );
    tmp = dst;
  }
  return 0;
}