Bitmap Conversion

Question

I'm trying to stream a webcam across from a client to a server but I'm having difficulty at the conversion from the byte array back to the bitmap on the server.

Here's the code:

public void handlerThread()
{
    Socket handlerSocket = (Socket)alSockets[alSockets.Count-1];
    NetworkStream networkStream = new
    NetworkStream(handlerSocket);
    int thisRead=0;
    int blockSize=1024;
    Byte[] dataByte = new Byte[blockSize];
    lock(this)
    {
        // Only one process can access
        // the same file at any given time
        while(true)
        {
            thisRead=networkStream.Read(dataByte,0,blockSize);

            pictureBox1.Image = byteArrayToImage(dataByte);
            if (thisRead==0) break;
        }
        fileStream.Close();
    }
    lbConnections.Items.Add("File Written");
    handlerSocket = null;
}

public Image byteArrayToImage(byte[] byteArrayIn)
{
    MemoryStream ms = new MemoryStream(byteArrayIn);  //here is my error
    Image returnImage = Image.FromStream(ms);
    return returnImage;
}

At the point marked above I get "Parameter is not valid" when trying to convert back to the image and crash. Any suggestions as to what I'm doing wrong?

Seems my problem was my buffer size was too small. Need to do a bit more testing first though. — windowsgm, Dec 04 '12 at 13:40

score 0 · Answer 1 · edited May 23 '17 at 12:18

Note this bit: Image.Save(..) throws a GDI+ exception because the memory stream is closed

You can create an extension method or remove the "this" for a traditional method. This looks the same as your code so I wonder if you have some type of encoding or other issue relatd to creating your underlying byte array?

public static Image ToImage(this byte[] bytes)
{
    // You must keep the stream open for the lifetime of the Image.
    // Image disposal does clean up the stream.

    var stream = new MemoryStream(bytes);
    return Image.FromStream(stream);
}

Bitmap Conversion

1 Answers1

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