How do I convert byte[] to Mat.
I am trying to get the LEGO EV3 to work with OpenCV. I have a working LEGO sample and a working OpenCV sample. The problem comes when when I try to merge the two samples. The video protocols are different. The lego video input is byte[] and the OpenCV output is Mat. I have tried conversion code from the blogs but have not gotten anything to work. How do I convert LEGO byte [] to OpenCV Mat? The two samples and my program follow … . . . My program ...
package my_PACKAGE;
import java.io.IOException; // PACKAGE
import org.opencv.core.Mat;
import org.opencv.core.MatOfByte;
import org.opencv.core.Point;
import org.opencv.core.Size;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;
import lejos.hardware.Brick;
import lejos.hardware.BrickFinder; // PACKAGE
import lejos.hardware.Button; // PACKAGE
import lejos.hardware.LocalBTDevice; // PACKAGE
import lejos.hardware.ev3.EV3; // PACKAGE
import lejos.hardware.lcd.Font; // PACKAGE
import lejos.hardware.lcd.GraphicsLCD; // PACKAGE
import lejos.hardware.video.Video; // PACKAGE
import lejos.hardware.video.YUYVImage; // PACKAGE
public class Email // CLASS
{ ///////////////////////////////////////////////////////////////////////////////////
//
private static final int WIDTH = 160; //
private static final int HEIGHT = 120; //
// private static final String WIDTH = null; //
//
//
public static void main(String[] args) // METHOD //
//
{ ///////////////////////////////////////////////////////////////////////// //
// //
Brick MyBrick; // //
MyBrick = BrickFinder.getLocal(); // //
String MyType; // //
MyType = MyBrick.getType(); // //
String MyName; // //
MyName = MyBrick.getName(); // //
LocalBTDevice MyIPAddressS; // //
MyIPAddressS = MyBrick.getBluetoothDevice(); // //
EV3 School_red_EV3; // //
School_red_EV3 = (EV3) BrickFinder.getLocal(); // //
Video Insten; // //
Insten = School_red_EV3.getVideo(); // //
GraphicsLCD GraphicsScreen; // //
GraphicsScreen = School_red_EV3.getGraphicsLCD(); // //
GraphicsScreen.setFont(Font.getSmallFont()); // //
try { // //
Insten.open(WIDTH,HEIGHT); // //
} catch (IOException e) { // //
// TODO Auto-generated catch block // //
e.printStackTrace(); // //
} // //
byte[] Still; // //
Still = Insten.createFrame(); // //
YUYVImage img; // //
img = new YUYVImage(Still, WIDTH, HEIGHT); // //
int threshold = 128; // //
GraphicsScreen.clear(); // //
GraphicsScreen.refresh(); // //
while (!Button.ESCAPE.isDown()) // //
{ //////////////////////////////////////////// // //
try { // //
Insten.grabFrame(Still); // //
} catch (IOException e) { // //
// TODO Auto-generated catch block // //
e.printStackTrace(); // //
} // //
threshold = img.getMeanY(); // //
img.display(GraphicsScreen, 0, 0, threshold); // //
} /////// // //
try { // //
Insten.close(); // //
} catch (IOException e) { // //
// TODO Auto-generated catch block // //
e.printStackTrace(); // //
} // //
GraphicsScreen.clear(); // //
Mat mat = null; // //
//Mat src = Still; // //
String filename = ((args.length > 0) ? args[0] : "lena.jpg"); // //
Object H; // //
mat = Imgcodecs.imdecode(new MatOfByte(Still), Imgcodecs.CV_LOAD_IMAGE_UNCHANGED); //
// Mat newImg = Mat(HEIGHT, WIDTH, CV_8UC1, Still + FRAMEINFO_SIZEF ); // //
// mat.put(0, 0, Still); // Error on this line // //
Mat src = mat; // //
Mat dst = null; // //
double i = 5; // //
Imgproc.blur(src, dst, new Size(i, i), new Point(-1, -1)); // //
} ////////////////////////////////////////////////////////////////////////////// //
//
} //////////////////////////////////////////////////////////////////////////////////
LEGO sample
package my_PACKAGE;
import java.io.IOException; // PACKAGE
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.core.Mat.*;
import org.opencv.core.MatOfByte;
import org.opencv.imgcodecs.Imgcodecs;
import lejos.hardware.Brick;
import lejos.hardware.BrickFinder; // PACKAGE
import lejos.hardware.Button; // PACKAGE
import lejos.hardware.LocalBTDevice; // PACKAGE
import lejos.hardware.ev3.EV3; // PACKAGE
import lejos.hardware.lcd.Font; // PACKAGE
import lejos.hardware.lcd.GraphicsLCD; // PACKAGE
import lejos.hardware.video.Video; // PACKAGE
import lejos.hardware.video.YUYVImage; // PACKAGE
public class Black_White_Camera // CLASS
{ //////////////////////////////////////////////////////////////
private static final int WIDTH = 160; //
private static final int HEIGHT = 120;
public static void main(String[] args) // METHOD /
{ ////////////////////////////////////////////////////////////
Brick MyBrick;
MyBrick = BrickFinder.getLocal();
String MyType;
MyType = MyBrick.getType();
if (MyType != "EV3")
{System.out.println ...
80% of the ill-formatted mess are unrelated to the problem.
please try to shorten it to the relevant part, and use proper formatting (mark it , press 10101 button)
(if noone can read it, noone will help you)
it's getting somewhat better ;)
byte[] Still;that's where the pixels are ?do a quick test like:
if that's true, maybe a simple:
does the trick already
(but note, that opencv has it in bgr order, while your logo thingy might be using rgb)
[UPDATE, 8UC1, not 8UC3 as stated before !!]
Add comment -- Try 2
THANK YOU This is a unique editor. It needs short lines and uses proportional spacing while the formatted text is not in proportional spacing. I have to type the post to see the published version so that I can correct it. I did not want to provide too little information as to hide the issue. However, considering the high quality of the advice, I guess the only confusion is mine. I thought that I had spent three hours editing the post before you even saw it. Now I see that you see my post immediately. I do not work at that pace. I believe that the post is up to your standards now.
My best research gets me
Except that CV_8UC1 cannot be resolved to a variable. I now find out that CV_8UC3 cannot be resolved to a variable
I am not importing CV_8UC1 or CV_8UC3. But, note that I am importing Mat and Improc.blur
CV_8UC3 in Java is addressed as CvType.CV_8UC3
The question makes an invalid assumption. While it is true that the LEGO webcam video/frame format is byte[], The pertinent OpenCV "Mat" method in Java receives the data format “ByteBuffer”. So, first I must convert from byte[] to "ByteBuffer".
When I try to execute
I get the message
This is similar to CV_8UC3 is undefined Do I need to make it "?.Mat"
By the way: I cannot find Mat(int, int, int, byte[]) in the Mat.class Mat(int, int, int, ByteBuffer) is in the Mat.class But I get that it is undefined Mat(int, int, int, Scalar) is in the Mat.class and I get that it is defined.