使用多个端口通过两对独立的Arducam和arduino Uno发送图像

Question

I am trying to send images via two ports namely COM5 and COM7. Following code does the most. Most significant part of the code is captureAndsaveImage method.

The problem is when i use both serial ports; images are getting distorted they feel like they are getting mixed up.

My question: Is it possible to use both port simaltaneously? What should i do such that there is no mixing up?

Don't mind second image's black circle it might have happened due to some signal losses in the second camera.

public class ReadPort {

    private static final  char[]COMMAND = {'*', 'R', 'D', 'Y', '*'};
    private static final int WIDTH = 320; //640;
    private static final int HEIGHT = 240; //480;
     SerialPort serialPort,serialPort2;

    public int[][] rgb2 = new int[WIDTH][HEIGHT];

    public static void main(String[] args) {
            ReadPort reader= new ReadPort();
    }

     public ReadPort() {
            int[][]rgb = new int[HEIGHT][WIDTH];
            try {

                serialPort = SerialPort.getCommPort("COM7");
                serialPort.openPort();
                inputStream = serialPort.getInputStream();
                serialPort.setComPortParameters(1000000, 
                        8, 
                        SerialPort.ONE_STOP_BIT, 
                        SerialPort.NO_PARITY);
                if(serialPort.isOpen()){
                    System.out.println("COM5 opened");
                }

                serialPort2 = SerialPort.getCommPort("COM5");
                serialPort2.openPort();
                inputStream2 = serialPort2.getInputStream();
                serialPort2.setComPortParameters(1000000, 
                        8, 
                        SerialPort.ONE_STOP_BIT, 
                        SerialPort.NO_PARITY);
                if(serialPort2.isOpen()){
                    System.out.println("COM7 opened");
                }


                int counter = 0;

                while(true) {

                        captureAndsaveImage( inputStream2,counter, rgb, "COM5");
                        captureAndsaveImage(inputStream, counter, rgb, "COM7");
                        counter++;



                }

            } catch (Exception e) {
                e.printStackTrace();
            }

     }

     public static void captureAndsaveImage(InputStream inputStream, int counter,int[][] rgb,String name) throws IOException{


        while(!isImageStart(inputStream, 0)){};

        System.out.print("Found image: " + counter);

        for (int y = 0; y < HEIGHT; y++) {
            for (int x = 0; x < WIDTH; x++) {
                    int temp =read(inputStream);
                    rgb[y][x] = ((temp&0xFF) << 16) | ((temp&0xFF) << 8) | (temp&0xFF);
            }
        }


        BMP bmp = new BMP();
        bmp.saveBMP("c:/out/" +name+"images/"+ counter + ".bmp", rgb);
        System.out.println(", Saved image:"+name+"images/"+counter+".bmp");

 }

    private static int read(InputStream inputStream) throws IOException {

        int temp = (char) inputStream.read();
        //System.out.print(temp);
        if (temp == -1) {
            throw new  IllegalStateException("Exit");
        }
        return temp;
        }


    private static boolean isImageStart(InputStream inputStream, int index) throws IOException {
        if (index < COMMAND.length) {
            if (COMMAND[index] == read(inputStream)) {
                return isImageStart(inputStream, ++index);
            } else {
                return false;
            }
        }
        return true;
    }

}

Edit : I used a debug statement like

    if(inputStream.available()>0){
            System.out.println(inputStream.toString());}

in the captureAndsaveImage method and i got output like

COM5 opened
COM7 opened
Found image: 
0com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@7f31245a
, Saved image:COM5images/0.bmp
Found image: 
0com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
, Saved image:COM7images/0.bmp
 Found image: 
 1com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@7f31245a
 , Saved image:COM5images/1.bmp
 Found image: 
 1com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
 , Saved image:COM7images/1.bmp
 Found image: 2, Saved image:COM5images/2.bmp
 Found image: 
 2com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
 , Saved image:COM7images/2.bmp
 Found image: 
 3com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@7f31245a
 , Saved image:COM5images/3.bmp
 Found image: 
 3com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
 , Saved image:COM7images/3.bmp
 Found image: 4, Saved image:COM5images/4.bmp
 Found image: 
 4com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
 , Saved image:COM7images/4.bmp
 Found image: 
 5com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@7f31245a
 , Saved image:COM5images/5.bmp
 Found image: 
5com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
, Saved image:COM7images/5.bmp
Found image: 6, Saved image:COM5images/6.bmp
Found image: 6, Saved image:COM7images/6.bmp
Found image: 
7com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@7f31245a
, Saved image:COM5images/7.bmp
Found image: 
7com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
, Saved image:COM7images/7.bmp
Found image: 8, Saved image:COM5images/8.bmp
Found image: 
8com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
, Saved image:COM7images/8.bmp
Found image: 
9com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@7f31245a
, Saved image:COM5images/9.bmp

Things i observe is that some lines are like

 Found image: 6, Saved image:COM5images/6.bmp

and most of them are

 Found image: 
5com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28
, Saved image:COM7images/5.bmp

What is the reason? As far as i know com.fazecast.jSerialComm.SerialPort$SerialPortInputStream@6d6f6e28 this is supposed to be address of the inputStream. But why it is not happening in some cases? (I am beginner in Serial communication.)

Answer 1

Hurray! I have solved my problem. Even though solution isn't elegant.

I put a block of code in the start of captureAndsaveImage method like

while(inputStream.available()>0){
            int temp=read(inputStream);

        }

And now I am getting cleared image. I have some vague idea how it worked but i would love if anyone can give logic for these.

Edit: I observe that distorted images were coming in odd frames. So the above code just skips those frames shows even frames which are not mixed up. :/

Answer 2

Your code seems to be very disorganized. For example, where you open COM5, your debug messages says it's opening COM7 and vice versa.

However, the bug causing the issue you raised in your question is with these lines of code:

while(true) {
    captureAndsaveImage( inputStream2,counter, rgb, "COM5");
    captureAndsaveImage(inputStream, counter, rgb, "COM7");
    counter++;
}

As you can see, you're storing the data from both image sources into the same array, rgb . Your code has an rgb2 , so I suspect you meant to use one of those with COM5 and the other for COM7, though the array declarations being at different scopes is strange. I would suggest you review your code, and perhaps focus on getting things working with one serial port/data source before introducing a second.

Edit: reading your comment and reviewing your error, I found another bug:

private static boolean isImageStart(InputStream inputStream, int index) throws IOException {
    if (index < COMMAND.length) {
        if (COMMAND[index] == read(inputStream)) {
            return isImageStart(inputStream, ++index);
        } 
        else {
            return false;
        }
    }
    return true;
}

Here, isImageStart() could return true if it works out that you missed the starting character in a stream. Essentially, since you recursively call isImageStart, if you start with a stream that doesn't contain the command character, you will run until you reach COMMAND.length , at which point, the next recursive call would skip the if (index < COMMAND.length) and return true. So, if you have a case where you started reading too soon (or too late), isImageStart() will still return true. Then, in CaptureAndSaveImage() , you still continue calling read on the inputstream and likely are reading stale data from the previous stream. Except by that point, the stream may be valid and depending on how fast data is coming in, you will have a mix of the previous image and the one currently being received.