C# -> Python 编码和解码网络摄像头流

Question

I've been having trouble figuring out how to pass a webcam image through a Named Pipe. Already accomplished getting the Server and Client to exchange data but can't figure out how to use the libraries to actually encode and decode an image properly. Right now my Python side just shows up as a Grey Image. Hopefully you could help guide me through this problem.

Here is my C# Block Encoding a Bitmap to a ByteArray and Passing it through a named Pipe:

public byte[] encodeImage(System.Drawing.Image imageIn)
    //Helper Function for turning Bitmap images into ByteArrays
    {
        using (var ms = new MemoryStream())
        {
            imageIn.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
            return ms.ToArray();
        }
    }

public void OnFrameReceive(object sender, NewFrameEventArgs eventArgs)
    {
        byte[] image_bytes;
        Console.WriteLine("Received new frame");
        Bitmap bitmap = (Bitmap)eventArgs.Frame.Clone();
        image_bytes = encodeImage(bitmap);
        writeToPipe(image_bytes);
    }

public void writeToPipe(byte[] frame)
    {
        if (server.IsConnected)
        {
            MemoryStream memoryStream = new MemoryStream();
            using (BinaryWriter writer = new BinaryWriter(memoryStream))
            {
                Console.WriteLine("Wrting to pipe");
                writer.Write(frame);
                int bufferLength = (memoryStream.ToArray().Length);
                server.Write(memoryStream.ToArray(), 0, bufferLength);
            }
            memoryStream.Close();
        }
        else
        {
            Console.WriteLine("Not connected");
        }

And here is the Python side receiving that data and trying to decode it:

def init_pipe_signal():
    print("At init_pipe_signal")
    bufferSize = 921600
    arraySize = int(math.sqrt(bufferSize))
    i = np.arange(bufferSize).reshape(arraySize, arraySize)

    fileHandle = win32file.CreateFile("\\\\.\\pipe\\Demo", win32file.GENERIC_READ | win32file.GENERIC_WRITE, 0, None, win32file.OPEN_EXISTING, 0, None)

    while True:
        response, data = win32file.ReadFile(fileHandle, bufferSize)

        if response == 0:
            try:
                frame = Image.frombytes("RGB", (480,640), data, decoder_name="raw")
                frame = np.array(frame)
                cv.imshow('Test',frame)
            
            except ValueError:
                print("Value Error Here")
    
        else:
            print("No pipe data")

Any guidance or help would be appreciated!

Answer 1

Got it! For those who are looking for the answer: Here is my C# Side

        public byte[] encodeImage(System.Drawing.Image imageIn)
    //Helper Function for turning Bitmap images into ByteArrays
    {
        using (var ms = new MemoryStream())
        {
            imageIn.Save(ms, ImageFormat.Bmp);
            return ms.ToArray();
        }
    }

    public void OnFrameReceive(object sender, NewFrameEventArgs eventArgs)
    {
        byte[] image_bytes;
        Console.WriteLine("Received new frame");
        Bitmap bitmap = (Bitmap)eventArgs.Frame.Clone();
        image_bytes = encodeImage(bitmap);
        writeToPipe(image_bytes);
    }
    public void writeToPipe(byte[] frame)
    {
        if (server.IsConnected)
        {
            MemoryStream memoryStream = new MemoryStream();
            using (BinaryWriter writer = new BinaryWriter(memoryStream))
            {

                Console.WriteLine("Wrting to pipe");
                writer.Write(frame);

                //int bufferLength = (memoryStream.ToArray().Length/32)*32;
                int bufferLength = (memoryStream.ToArray().Length);
                server.Write(memoryStream.ToArray(), 0, bufferLength);
                Console.WriteLine(memoryStream.ToArray().Length);
            }
            /*
            Not sure if Memory Stream needs to be closed here (after every Write) 
            or after every time the server finishes.
            Test performance for both
            */
            memoryStream.Close();
        }
        else
        {
            Console.WriteLine("NOPE NOT CONNECTED");
        }
    }

and here is the python decoding side:

def init_pipe_signal():
    print("At init_pipe_signal")
    bufferSize = 921654
    fileHandle = win32file.CreateFile("\\\\.\\pipe\\Demo", win32file.GENERIC_READ | win32file.GENERIC_WRITE, 0, None, win32file.OPEN_EXISTING, 0, None)
while True:
    response, data = win32file.ReadFile(fileHandle, bufferSize)

    if response == 0:
        try:
            frame = np.array(Image.frombytes("RGB", (640, 480), data))
            frame = np.rot90(frame, 2)
            cv2.imshow("Test", frame)
            if cv2.waitKey(1) & 0xFF == ord('q'):
                break

        except ValueError:
            print("Value Error Here")
    
    else:
        print("No pipe data")