c++ - 通过标准平均 C++ 模糊图像

Question

我试图在不使用 opencv 预定义函数(如 blur())的情况下模糊图像。我使用的是标准平均值而不是加权平均值。这是我的代码，但结果仍然与输入图像相同。这是 3x3 的。

    IplImage* img = cvLoadImage(argv[1]);
    IplImage* dst = cvCloneImage(img);

    height = img->height;
    width = img->width;
    step = img->widthStep;
    channels = img->nChannels;
    data = (uchar *)img->imageData;

    height2    = dst->height; // row
    width2     = dst->width; // col
    step2      = dst->widthStep; // size of aligned image row in bytes
    channels2  = dst->nChannels; 
    dstData      = (uchar *)dst->imageData;
    int total = 0;

    //blur
    for (i = 0; i < height; i++) {
        for (j = 0; j < width; j++) {          
           for (x = 0; x <= 2; x++)
                for (y = 0; y <= 2; y++)
                    total =(data[x-1,y-1]+data[x-1,y]+data[x-1,y+1]+
                            data[x,y-1]+data[x,y]+data[x,y+1]+
                            data[x+1,y-1]+data[x+1,y]+data[x+1,y+1])/9;
                    dstData[i,j] = total;
                    }
            }

我想我的问题出在这个上

                       total =(data[x-1,y-1]+data[x-1,y]+data[x-1,y+1]+
                       data[x,y-1]+data[x,y]+data[x,y+1]+
                       data[x+1,y-1]+data[x+1,y]+data[x+1,y+1])/9;
                       dstData[i,j] = total;

可以做什么？

Answer 1

一个完整的程序，展示了如何做到这一点。你有几个错误，1)不正确的像素访问(http://www.comp.leeds.ac.uk/vision/opencv/iplimage.html)。 2) 模糊循环是错误的，你总是从左上角的 3x3 角获取数据。如果像素访问正确，你应该在 dst 中得到一个恒定的图像。

另一件事是您还需要处理 channel 信息，程序通过读取单个 channel 图像来绕过它。否则你需要为每个 channel 做模糊

#include <opencv2/opencv.hpp>


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

    IplImage* img = cvLoadImage("c:/data/2.jpg",0);
    IplImage* dst = cvCloneImage(img);
    int height,width,step,channels;
    int height2,width2,step2,channels2;

    height = img->height;
    width = img->width;
    step = img->widthStep;
    channels = img->nChannels;
    uchar* data = (uchar *)img->imageData;

    height2    = dst->height; // row
    width2     = dst->width; // col
    step2      = dst->widthStep; // size of aligned image row in bytes
    channels2  = dst->nChannels; 
    uchar* dstData      = (uchar *)dst->imageData;
    int total = 0;
    int i,j,x,y,tx,ty;
    //blur
    for (i = 0; i < height; i++) {
        for (j = 0; j < width; j++) {   
            int ksize=3;
            total=0;
            for (x = -ksize/2; x <=ksize/2; x++)
                for (y = -ksize/2; y <=ksize/2; y++)
                {
                    tx=i+x;
                    ty=j+y;
                    if(tx>=0&&tx<height && ty>=0 && ty<width)
                    {
                        total+=data[tx*step+ty];
                    }
                }

            dstData[i*step+j] = total/ksize/ksize;
        }
    }
    cvShowImage("img",img);
    cvShowImage("dst",dst);
    cvWaitKey(0);
}