C#窗体bitmap执行处理图片内存不足

 Bitmap originalImage =(Bitmap)Bitmap.FromFile(originalImagePath);
                int thumWidth = width;//缩略图的宽度        
                int thumHeight = height; //缩略图的高度       
                int x = 0; int y = 0;
                int originalWidth = originalImage.Width;//原始图片的宽度       
                int originalHeight = originalImage.Height;//原始图片的高度        
                switch (model)
                {
                    case "HW": //指定高宽缩放,可能变形                
                        break;
                    case "W": //指定宽度,高度按照比例缩放               
                        thumHeight = originalImage.Height * width / originalImage.Width;
                        break;
                    case "H": //指定高度,宽度按照等比例缩放                
                        thumWidth = originalImage.Width * height / originalImage.Height;
                        break;
                    case "Cut":
                        if ((double)originalImage.Width / (double)originalImage.Height > (double)thumWidth / (double)thumHeight)
                        {
                            originalHeight = originalImage.Height;
                            originalWidth = originalImage.Height * thumWidth / thumHeight; y = 0; x = (originalImage.Width - originalWidth) / 2;
                        }
                        else
                        {
                            originalWidth = originalImage.Width;
                            originalHeight = originalWidth * height / thumWidth; x = 0;
                            y = (originalImage.Height - originalHeight) / 2;
                        }
                        break;
                    default:
                        break;
                }  //新建一个bmp图片        
                System.Drawing.Image bitmap = new System.Drawing.Bitmap(thumWidth, thumHeight); //新建一个画板        
                System.Drawing.Graphics graphic = System.Drawing.Graphics.FromImage(bitmap); //设置高质量查值法       
                graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;        //设置高质量，低速度呈现平滑程度   
                graphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;        //清空画布并以透明背景色填充       
                graphic.Clear(System.Drawing.Color.Transparent);        //在指定位置并且按指定大小绘制原图片的指定部分       
                graphic.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, thumWidth, thumHeight), new System.Drawing.Rectangle(x, y, originalWidth, originalHeight),
               System.Drawing.GraphicsUnit.Pixel);
               originalImage.Dispose();
               graphic.Dispose();
               GC.Collect();
                try
                {
                    bitmap.Save(thumNailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
                }
                catch (Exception ex) { throw ex; }
                finally { originalImage.Dispose(); bitmap.Dispose(); graphic.Dispose(); GC.Collect(); }
大家看下我这段代码有问题吗？为什么执行过一段时间会提示Bitmap originalImage =(Bitmap)Bitmap.FromFile(originalImagePath);这一句代码内存不足呢？

12 个解决方案