C#结合GDAL实现中值滤波

 private void btnMiddleFilter_Click(object sender, EventArgs e)
        {
            string openFileName = "";
            OpenFileDialog ofd = new OpenFileDialog();
            if(ofd.ShowDialog()==DialogResult.OK)
            {
                openFileName = ofd.FileName;
            }
            
            Gdal.AllRegister();

            //更改读写权限
            Dataset srcDs = Gdal.Open(openFileName, Access.GA_Update);

            DataType srcType = srcDs.GetRasterBand(1).DataType;

            int bandCount = srcDs.RasterCount;
            int srcWidth = srcDs.RasterXSize;
            int srcHeight = srcDs.RasterYSize;

            Debug.WriteLine("原始影像数据类型是：{0}", srcType);
            Debug.WriteLine("原始影像的列数：{0}", srcWidth);
            Debug.WriteLine("原始影像的行数：{0}", srcHeight);


            int[] bandArray = new int[bandCount];
            for (int i = 0; i < bandCount; i++)
            {
                bandArray[i] = i + 1;
            }

            if (srcType == DataType.GDT_UInt16)
            {
                int[] dataArray = new int[srcWidth * srcHeight * bandCount];
                int[] newArray = new int[srcWidth * srcHeight * bandCount];
                srcDs.ReadRaster(0, 0, srcWidth, srcHeight, dataArray, srcWidth, srcHeight, bandCount, bandArray, 0, 0, 0);

                /***********中值滤波实现**************/
                int[] temp = new int[5];
                for (int i = 0; i < srcHeight; i++)
                {
                    for (int j = 0; j < srcWidth - 2; j++)
                    {
                        if (j >= 2)//从第三列开始
                        {
                            temp[0] = dataArray[i * srcWidth + j - 2];
                            temp[1] = dataArray[i * srcWidth + j - 1];
                            temp[2] = dataArray[i * srcWidth + j];
                            temp[3] = dataArray[i * srcWidth + j + 1];
                            temp[4] = dataArray[i * srcWidth + j + 2];
                            Array.Sort(temp);//排序
                            newArray[i * srcWidth + j] = temp[2];
                        }
                        else
                            newArray[i * srcWidth + j] = dataArray[i * srcWidth + j];
                    }
                }

                //将更新数值的数据重新写入图像
                srcDs.WriteRaster(0, 0, srcWidth, srcHeight, newArray, srcWidth, srcHeight, bandCount, bandArray, 0, 0, 0);

                srcDs.FlushCache();
            }
            //最后释放资源
            srcDs.Dispose();
            MessageBox.Show("中值滤波：success");
            
        }

原图：

原图细节：

中值滤波结果（不明显，需要结合下面的细节展示来观察）：

细节展示：