cs50 Pset4 图像模糊问题

Question

现在已经被这个问题困扰了一段时间，我很困惑为什么我的代码没有按预期编译。我应该将 5 号像素的颜色值与其周围像素进行平均，这样生成的图像就会看起来模糊。这是我的代码：

    // Blur image
    // 1 | 2 | 3
    // -   -   -
    // 4 | 5 | 6
    // -   -   -
    // 7 | 8 | 9
    //assuming i is 5
    void blur(int height, int width, RGBTRIPLE image[height][width])
    {
        RGBTRIPLE copy[height][width];
        for (int i = 0; i < height; i++)
        {
            for (int j = 0; j < width; j++)
            {
                copy[i][j] = image[i][j];
            }
        }
        for (int i = 0; i < height; i++)
        {
            for (int j = 0; j < width; j++)
            {
                int red = 0;
                int green = 0;
                int blue = 0;
                float counter = 0;

                // 5
                red += copy[i][j].rgbtRed;
                green += copy[i][j].rgbtGreen;
                blue += copy[i][j].rgbtBlue;
                counter++;

                //1
                if (i - 1 > -1 && j - 1 > -1)
                {
                    red += copy[i - 1][j].rgbtRed;
                    green += copy[i - 1][j].rgbtGreen;
                    blue += copy[i - 1][j].rgbtBlue;
                    counter++;
                }
                // 2
                if (i - 1 > -1)
                {
                    red += copy[i - 1][j].rgbtRed;
                    green += copy[i - 1][j].rgbtGreen;
                    blue += copy[i - 1][j].rgbtBlue;
                    counter++;
                }
                // 3
                if (i - 1 > -1 && j + 1 < height)
                {
                    red += copy[i - 1][j + 1].rgbtRed;
                    green += copy[i - 1][j + 1].rgbtGreen;
                    blue += copy[i - 1][j + 1].rgbtBlue;
                    counter++;
                }
                // 4
                if (j - 1 > -1)
                {
                    red += copy[i][j - 1].rgbtRed;
                    green += copy[i][j - 1].rgbtGreen;
                    blue += copy[i][j - 1].rgbtBlue;
                    counter++;
                }
                // 6
                if (j + 1 < width)
                {
                    red += copy[i][j + 1].rgbtRed;
                    green += copy[i][j + 1].rgbtGreen;
                    blue += copy[i][j + 1].rgbtBlue;
                    counter++;
                }
                // 7
                if (i + 1 < height && j - 1 > -1)
                {
                    red += copy[i + 1][j - 1].rgbtRed;
                    green += copy[i + 1][j - 1].rgbtGreen;
                    blue += copy[i + 1][j - 1].rgbtBlue;
                    counter++;
                }
                // 8
                if (i + 1 < height)
                {
                    red += copy[i + 1][j].rgbtRed;
                    green += copy[i + 1][j].rgbtGreen;
                    blue += copy[i + 1][j].rgbtBlue;
                    counter++;
                }
                // 9
                if (i + 1 < height && j + 1 < width)
                {
                    red += copy[i + 1][j + 1].rgbtRed;
                    green += copy[i + 1][j + 1].rgbtGreen;
                    blue += copy[i + 1][j + 1].rgbtBlue;
                    counter++;
                }

                image[i][j].rgbtRed = round(red/counter);
                image[i][j].rgbtGreen = round(green/counter);
                image[i][j].rgbtBlue = round(blue/counter);
            }
        }
        return;
    }

我从中心像素开始检查并检查周围像素的存在，并相应地使用其周围像素的值来平均中心像素的值。我的代码编译得很好，当我运行它时它似乎正在工作。当我尝试运行 debug50 时；当我进行一些手动测试时，所有的值都会加起来。但是，当我尝试实施 Check50 时，会出现此错误消息

expected "127 140 149\n", not "130 143 153\n"
Log
testing with sample 3x3 image
first row: (10, 20, 30), (40, 50, 60), (70, 80, 90)
second row: (110, 130, 140), (120, 140, 150), (130, 150, 160)
third row: (200, 210, 220), (220, 230, 240), (240, 250, 255)
running ./testing 3 0...
checking for output "127 140 149\n"...

Expected Output:
127 140 149
Actual Output:
130 143 153

不太确定我的代码出了什么问题。任何建议将不胜感激！

Answer 1

                //1
                if (i - 1 > -1 && j - 1 > -1)
                {
                    red += copy[i - 1][j].rgbtRed;
                    green += copy[i - 1][j].rgbtGreen;
                    blue += copy[i - 1][j].rgbtBlue;
                    counter++;
                }

您使用了“j”，而它应该是“j - 1”。应该是这样的：

                //1
                if (i - 1 > -1 && j - 1 > -1)
                {
                    red += copy[i - 1][j - 1].rgbtRed;
                    green += copy[i - 1][j - 1].rgbtGreen;
                    blue += copy[i - 1][j - 1].rgbtBlue;
                    counter++;
                }