读取图像 \examples\data\convec.dat，并对它进行均值平滑（smooth 和median），另外利用Sobel和Roberts函数使用以下3*3的窗口对图像进行卷积。给出IDL编程代码及其运行结果。(The image \\examples\\data\\convec.dat is read, and its mean smoothing (smooth and median) is performed. In addition, Sobel and Roberts functions are used to convolution the image with the following 3*3 window. The IDL programming code and its running results are given.)