以下均針對opencv1.0
第一種方法：使用cvGet2D及cvSet2D

對於單通道影象：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_8U, 1);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            CvScalar s;
            //s = cvGet2D(img, i, j);// get the (i,j) pixel value
 

            s.val[0] = 255;
            cvSet2D(img, i, j, s);// set the (i,j) pixel value
        }
    }

對於多通道影象：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_32F, 3);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
 

        {
            CvScalar s;
            //s = cvGet2D(img, i, j);// get the (i,j) pixel value
            s.val[0] = 0;//B
            s.val[1] = 100;//G
            s.val[2] = 50;//R
            cvSet2D(img, i, j, s);// set the (i,j) pixel value
        }
    }

第二種方法：直接訪問
對於單通道影象：

    IplImage* img = cvCreateImage(cvSize(640
 
, 480), IPL_DEPTH_8U, 1);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            ((uchar*)(img->imageData + i*img->widthStep))[j] = 255;//img->imagedata是指向影象資料第一個畫素的指標，widthStep是指每一行的畫素所佔的位元組數
        }
    }

對於多通道影象：
多通道位元組型：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_8U, 3);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            ((uchar*)(img->imageData + i*img->widthStep))[j*img->nChannels + 0] = 0;//img->imagedata是指向影象資料第一個畫素的指標，widthStep是指每一行的畫素所佔的位元組數
            ((uchar*)(img->imageData + i*img->widthStep))[j*img->nChannels + 1] = 100;
            ((uchar*)(img->imageData + i*img->widthStep))[j*img->nChannels + 2] = 50;
        }
    }

多通道浮點型：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_32F, 3);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            ((float*)(img->imageData + i*img->widthStep))[j*img->nChannels + 0] = 0;//img->imagedata是指向影象資料第一個畫素的指標，widthStep是指每一行的畫素所佔的位元組數
            ((float*)(img->imageData + i*img->widthStep))[j*img->nChannels + 1] = 100;
            ((float*)(img->imageData + i*img->widthStep))[j*img->nChannels + 2] = 50;
        }
    }

第三種方法：指標訪問
對於單通道影象：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_8U, 1);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            int step = img->widthStep / sizeof(uchar);
            uchar*data = (uchar *)img->imageData;
            data[i*step + j] = 255;
        }
    }

對於多通道位元組型影象：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_8U, 3);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            for (int k = 0; k < img->nChannels; k++)//width對應影象的列
            {
                int step = img->widthStep / sizeof(uchar);
                int channels = img->nChannels;
                uchar*data = (uchar *)img->imageData;
                data[i*step + j*channels+k] = 255;
            }
        }
    }

對於多通道浮點型：

    IplImage* img = cvCreateImage(cvSize(640, 480), IPL_DEPTH_32F, 3);
    for (int i = 0; i < img->height; i++)//height對應影象的行
    {
        for (int j = 0; j < img->width; j++)//width對應影象的列
        {
            for (int k = 0; k < img->nChannels; k++)//width對應影象的列
            {
                int step = img->widthStep / sizeof(float);
                int channels = img->nChannels;
                float*data = (float *)img->imageData;
                data[i*step + j*channels+k] = 255;
            }
        }
    }