拆分tiff报错修复Bitmap/Image.Save()报错“GDI 中发生一般性错误”

 async Task<List<string>> GetJpegFileNamesFromTiff(string fileName, string saveFolder)
        {
            var imageFileNameList = new List<string>();
            using (var image = System.Drawing.Image.FromFile(fileName))
            {
                var frameDimension = new System.Drawing.Imaging.FrameDimension(image.FrameDimensionsList[0]);
                var frameCount = image.GetFrameCount(frameDimension);
                for (var frame = 0; frame < frameCount; frame++)
                {
                    var savePath = Path.Combine(saveFolder, $"{System.Guid.NewGuid()}.jpg");
                    try
                    {
                        image.SelectActiveFrame(frameDimension, frame);
                        //image.Save(savePath, System.Drawing.Imaging.ImageFormat.Png);
                        //使用以下方法
                        var oldImg = new System.Drawing.Bitmap(image);
                        Bitmap img = new Bitmap(oldImg);
                        Graphics draw = Graphics.FromImage(img);
                        draw.DrawImage(oldImg, 0, 0, oldImg.Width, oldImg.Height);
                        oldImg.Dispose();
                        img.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);
                        img.Dispose();
                        draw.Dispose();
                    }
                    catch (Exception ex)
                    {
                        throw new Exception($"拆分tif文件'{fileName}'出错,{ex.Message}", ex);
                    }
                    imageFileNameList.Add(savePath);
                }
            }
            return imageFileNameList;
        }