Question

我试图将R8G8B8A8图像转换为R8G8B8图像，我现在得到的是图像，但是有很多扫描线，我每个像素的字节数是4个字节，32位。

图像缓冲区的类型为unsigned char [width * height * 4]，它是源，目标是unsigned char [width * height * 3]。

    int j = 0;
    int i = 0;
    for (int k = 0; k < (width*height); k++)
    {
        for(int b = 0; b < 3; b++)
        {
            dst[i + b] = src[j + b];

        }
        i+=3;
        j+=4;
    }

Answer 1

你可以这样做：

for (int k = 0; k < width*height; k++)
{
    for(int b = 0; b < 3; b++)
    {
        dst[k*3 + b] = src[k*4 + b];

    }
}

Answer 2

目标图像可能需要在4字节边界上对齐的行：

InvalidArgumentError: You must feed a value for placeholder tensor 'yy' with dtype int32
     [[Node: yy = Placeholder[dtype=DT_INT32, shape=[], _device="/job:localhost/replica:0/task:0/cpu:0"]()]]
Caused by op 'yy', defined at:
  File "/opt/conda/lib/python3.6/runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "/opt/conda/lib/python3.6/runpy.py", line 85, in _run_code
    exec(code, run_globals)

将R8G8B8A8映像复制到R8G8B8

2 个答案: