Warning: file_get_contents(/data/phpspider/zhask/data//catemap/2/csharp/283.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181

Warning: file_get_contents(/data/phpspider/zhask/data//catemap/5/ruby-on-rails-4/2.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
Image.FromStream()在图像处理时发出C#_C#_Imaging - Fatal编程技术网

Image.FromStream()在图像处理时发出C#

Image.FromStream()在图像处理时发出C#,c#,imaging,C#,Imaging,我正在使用JPG图像类型,这一行image=image.FromStream(ms)给出错误参数无效。 这个代码有什么问题 private void button3_Click(object sender, EventArgs e) { Image partial=null; Rectangle bounds; Guid id; if (diff != null)

我正在使用JPG图像类型,这一行
image=image.FromStream(ms)给出错误
参数无效
。 这个代码有什么问题

        private void button3_Click(object sender, EventArgs e)
        {
          Image partial=null;
          Rectangle bounds;
          Guid id;

          if (diff != null)
          {
            ImageConverter converter = new ImageConverter();
            var data = (byte[])converter.ConvertTo(diff, typeof(byte[]));

            UnpackScreenCaptureData(data, out partial, out bounds,out id);
            Image imgfirst = (Image)firstImg;
            UpdateScreen(ref imgfirst, partial, bounds);
          }
        }

        public static void UnpackScreenCaptureData(byte[] data, out Image image, out Rectangle bounds, out Guid id)
        {
          // Unpack the data that is transferred over the wire.
          // Create byte arrays to hold the unpacked parts.
          const int numBytesInInt = sizeof(int);
          int idLength = Guid.NewGuid().ToByteArray().Length;
          int imgLength = data.Length - 4 * numBytesInInt - idLength;
          byte[] topPosData = new byte[numBytesInInt];
          byte[] botPosData = new byte[numBytesInInt];
          byte[] leftPosData = new byte[numBytesInInt];
          byte[] rightPosData = new byte[numBytesInInt];
          byte[] imgData = new byte[imgLength];
          byte[] idData = new byte[idLength];

          // Fill the byte arrays.
          Array.Copy(data, 0, topPosData, 0, numBytesInInt);
          Array.Copy(data, numBytesInInt, botPosData, 0, numBytesInInt);
          Array.Copy(data, 2 * numBytesInInt, leftPosData, 0, numBytesInInt);
          Array.Copy(data, 3 * numBytesInInt, rightPosData, 0, numBytesInInt);
          Array.Copy(data, 4 * numBytesInInt, imgData, 0, imgLength);
          Array.Copy(data, 4 * numBytesInInt + imgLength, idData, 0, idLength);

          // Create the bitmap from the byte array.          
          MemoryStream ms = new MemoryStream(imgData, 0, imgData.Length);
          ms.Write(imgData, 0, imgData.Length);
          image = Image.FromStream(ms);
          ....
        }

我认为您必须将
内存流
重置为位置0。 您可以通过调用内存流上的
Seek()
方法来实现这一点:

MemoryStream ms = new MemoryStream(imgData, 0, imgData.Length);
ms.Write(imgData, 0, imgData.Length);

ms.Seek(0, SeekOrigin.Begin);  // Set stream position to 0.    

image = Image.FromStream(ms);

抛出的异常是什么?当这一行“image=image.FromStream(ms);”执行时,我得到错误,错误消息是“Parameter is not valid”。我认为有一个很小的错误,我无法理解。到底什么是差异?它来自哪里?我试着比较两张jpg图片。第一个jpg图像存储在第一个IMG变量中,第二个jpg图像存储在第二个IMG变量中,两个图像之间的差异存储在差异变量中。同样,这没有任何意义:
MemoryStream ms=new MemoryStream(imgData,0,imgData.Length);ms.Write(imgData,0,imgData.Length)从数组创建流,然后再将该数组写入流?@Thomas:您是否比较了imgLength、topPosData、,。。。和原来的一样?我认为我们确实需要更多的代码来帮助您。我认为这个答案不正确。imgData被写入同一个流两次。