opencv-图像添加边界（填充）

为图像填充边界，以便进行滤波，卷积等有关图像边界处理的操作。

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

using namespace cv;

//全局变量
Mat src, dst;
int top, bottom, left, right;//定义边界大小
int borderType;//边界处理类型
Scalar value;
char* window_name = "copyMakeBorder Demo";
RNG rng(12345);

int main( int argc, char** argv )
{

int c;

//加载图像
src = imread( argv[1] );

if( !src.data )
{ return -1;
printf(" No data entered, please enter the path to an image file \n");
}

/// Brief how-to for this program
printf( "\n \t copyMakeBorder Demo: \n" );
printf( "\t -------------------- \n" );
printf( " ** Press 'c' to set the border to a random constant value \n");
printf( " ** Press 'r' to set the border to be replicated \n");
printf( " ** Press 'ESC' to exit the program \n");

//创建窗口
namedWindow( window_name, CV_WINDOW_AUTOSIZE );

//初始化滤波参数
top = (int) (0.05*src.rows); bottom = (int) (0.05*src.rows);
left = (int) (0.05*src.cols); right = (int) (0.05*src.cols);
dst = src;

imshow( window_name, dst );

while( true )
{
c = waitKey(500);

if( (char)c == 27 )//按ESC退出程序
{ break; }
else if( (char)c == 'c' )
{ borderType = BORDER_CONSTANT; }
else if( (char)c == 'r' )
{ borderType = BORDER_REPLICATE; }

value = Scalar( rng.uniform(0, 255), rng.uniform(0, 255), rng.uniform(0, 255) );
copyMakeBorder( src, dst, top, bottom, left, right, borderType, value );

imshow( window_name, dst );
}

return 0;
}