CS50 过滤器：我收到一个我不熟悉的新错误

Question

我已经研究 cs50 的边缘过滤功能几个小时了。它看起来不错，但我收到了一个看起来很可怕的错误，我不明白这是我的代码：

// Detect edges
void edges(int height, int width, RGBTRIPLE image[height][width])
{
RGBTRIPLE copy[height][width];

for (int h = 0; h < height; h++)
{
    for (int w = 0; w < width; w++)
    {
        copy[h][w] = image[h][w];
    }
}

for (int y = 0; y < height; y++)
{
    for (int x = 0; x < width; x++)
    {
        float gxred = 0;
        float gxgreen = 0;
        float gxblue = 0;
        float gyred = 0;
        float gygreen = 0;
        float gyblue = 0;
        for (int r = -1; r < 2; r++)
        {
            for (int s = -1; s < 2; s++)
            {
                if ((y + r < height && y + r >= 0) && (x + s < width && x + s >= 0))
                {
                    if (r == -1)
                    {
                        gxred = copy[y + r][x + s].rgbtRed * s;
                        gxgreen = copy[y + r][x + s].rgbtGreen * s;
                        gxblue = copy[y + r][x + s].rgbtBlue * s;
                        gyred = copy[x + s][y + r].rgbtRed * s;
                        gygreen = copy[x + s][y + r].rgbtGreen * s;
                        gyblue = copy[x + s][y + r].rgbtBlue * s;
                    }
                    if (r == 0)
                    {
                        gxred = copy[y + r][x + s].rgbtRed * (s * 2);
                        gxgreen = copy[y + r][x + s].rgbtGreen * (s * 2);
                        gxblue = copy[y + r][x + s].rgbtBlue * (s * 2);
                        gyred = copy[x + s][y + r].rgbtRed * (s * 2);
                        gygreen = copy[x + s][y + r].rgbtGreen * (s * 2);
                        gyblue = copy[x + s][y + r].rgbtBlue * (s * 2);
                    }
                    if (r == 1)
                    {
                        if (s * s == 1)
                        {
                            gxred = copy[y + r][x + s].rgbtRed * (s * s);
                            gxgreen = copy[y + r][x + s].rgbtGreen * (s * s);
                            gxblue = copy[y + r][x + s].rgbtBlue * (s * s);
                            gyred = copy[x + s][y + r].rgbtRed * (s * s);
                            gygreen = copy[x + s][y + r].rgbtGreen * (s * s);
                            gyblue = copy[x + s][y + r].rgbtBlue * (s * s);
                        }
                        else
                        {
                            gxred = copy[y + r][x + s].rgbtRed * (s + 1);
                            gxgreen = copy[y + r][x + s].rgbtGreen * (s + 1);
                            gxblue = copy[y + r][x + s].rgbtBlue * (s + 1);
                            gyred = copy[x + s][y + r].rgbtRed * (s + 1);
                            gygreen = copy[x + s][y + r].rgbtGreen * (s + 1);
                            gyblue = copy[x + s][y + r].rgbtBlue * (s + 1);    
                        }

                    }

                }
            }
        }
        image[y][x].rgbtRed = round(sqrt((gxred * gxred) + (gyred * gyred)));
        image[y][x].rgbtGreen = round(sqrt((gxgreen * gxgreen) + (gygreen * gygreen)));
        image[y][x].rgbtBlue = round(sqrt((gxblue * gxblue) + (gyblue * gyblue)));

        image[y][x].rgbtRed = image[y][x].rgbtRed % 256;
        image[y][x].rgbtGreen = image[y][x].rgbtGreen % 256;
        image[y][x].rgbtBlue = image[y][x].rgbtBlue % 256;
    }
}
return;
}

这是我的错误

helpers.c:169:37: runtime error: 261 is outside the range of representable values of type 
'unsigned char'
UndefinedBehaviorSanitizer:DEADLYSIGNAL
==5405==ERROR: UndefinedBehaviorSanitizer: SEGV on unknown address 0x7ffea18b01fa (pc 
0x000000429bb3 bp 0x7ffea18af1a0 sp 0x7ffea17fe250 T5405)
==5405==The signal is caused by a READ memory access.
#0 0x429bb2  (/home/ubuntu/pset4/filter/filter+0x429bb2)
#1 0x42330e  (/home/ubuntu/pset4/filter/filter+0x42330e)
#2 0x7f7c0b22eb96  (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
#3 0x402e19  (/home/ubuntu/pset4/filter/filter+0x402e19)

UndefinedBehaviorSanitizer can not provide additional info.
==5405==ABORTING

这会将我带到最后这一行：

image[y][x].rgbtGreen = round(sqrt((gxgreen * gxgreen) + (gygreen * gygreen)));

如果有人能解释这种错误的含义，我将不胜感激。而且，如果对我的代码提出任何批评，我将不胜感激，我正在努力做到这一点。

Answer 1

RGB 值可以是 0 到 255 之间的任何值。

您以某种方式将该行中的 RGB 值分配给了超出范围的 261。

在分配给 rgb 值之前，我会在下面的代码中打印值。

round(sqrt((gxgreen * gxgreen) + (gygreen * gygreen)))

然后检查为什么 round 内部给出 261。一旦你解决了这个问题，你就可以开始了。

CS50 过滤器：我收到一个我不熟悉的新错误

CS50 filter: I'm getting a new error which I'm not familiar with

c

filter

cs50