opencv 筆記12 Imgproc_Pyramid

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

using namespace cv;

/// 全局變量
Mat src, dst, tmp;
char* window_name = "Pyramids Demo";


/**
 * @函數 main
 */
int main( int argc, char** argv )
{
  /// 指示說明
  printf( "\n Zoom In-Out demo  \n " );
  printf( "------------------ \n" );
  printf( " * [u] -> Zoom in  \n" );
  printf( " * [d] -> Zoom out \n" );
  printf( " * [ESC] -> Close program \n \n" );

  /// 測試圖像 - 尺寸必須能被 2^{n} 整除
  src = imread( "../images/chicky_512.jpg" );
  if( !src.data )
    { printf(" No data! -- Exiting the program \n");
      return -1; }

  tmp = src;
  dst = tmp;

  /// 創建顯示窗口
  namedWindow( window_name, CV_WINDOW_AUTOSIZE );
  imshow( window_name, dst );

  /// 循環
  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 \n" );
      }
    else if( (char)c == 'd' )
     { pyrDown( tmp, dst, Size( tmp.cols/2, tmp.rows/2 ) );
       printf( "** Zoom Out: Image / 2 \n" );
     }

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

void pyrUp(const Mat& src, Mat& dst, const Size& dstsize=Size())

void pyrDown(const Mat& src, Mat& dst, const Size& dstsize=Size())

Parameters:

src – The source image dst – The destination image. It will have the specified size and the same type as src dstsize – Size of the destination image. By default it is computed as Size(src.cols*2, (src.rows*2) . But in any case the following conditions should be satisfied: \begin{array}{l} | \texttt{dstsize.width} -src.cols*2| \leq ( \texttt{dstsize.width} \mod 2) \\ | \texttt{dstsize.height} -src.rows*2| \leq ( \texttt{dstsize.height} \mod 2) \end{array}