Running matlab code from within Processing

daddydean

Hi there, I would like to know if there is way to run a matlab code from within Processing... The code I am interested in using is: http://ceng.anadolu.edu.tr/cv/EDPF/
Which is C++ as far as I am aware.
I've heard of a thing called "javabuilder" for matlab, but im not sure how I could use it in this situation. Can it be done? Cheers

jeremydouglass

Do you have MATLAB separately installed on your system, and are your trying to invoke a MATLAB script from within your sketch, e.g. with exec()?

MATLAB is proprietary, licensed software -- I don't believe that you can run it without MATLAB in any other environment, by design.

daddydean

@jeremydouglass, hey thanks for the response....I ended up getting the c++ source code for this...though it still isnt going to help since there is no c++ mode in Processing.
Ill ask in a different question, but here as well since its still a line segment detection code, how can I import https://github.com/anfractuosity/LSD
into Processing? Where would I start?

jeremydouglass

If you want to do Processing-like coding in C++, here is always openFrameworks:

• http://openframeworks.cc/

If you are using a Java library instead, you can put it in a /code subfolder of your sketch -- or drag-and-drop onto the PDE window to import.

• https://forum.processing.org/two/discussion/24090/installing-java-library

daddydean

Cool yeah, I've been using Openframeworks as well, still prefer Processing though.
Great, I should have figured that one out on my own lol, too easy.
I think its working, though im not getting anything other than a grey box...is there something Im missing here?
Its supposed to use the piet image.

GoToLoop

We can mix ".pde" & ".java" files in the same folder together w/ the PDE (Processing's IDE).

jeremydouglass

I think its working, though im not getting anything other than a grey box...is there something Im missing here?

There is no way for us to know what might be wrong unless you share an MCVE.

daddydean

I literally just dragged and dropped all the java files from the github into a sketch in Processing: https://github.com/anfractuosity/LSD

Basically what the code is supposed to do is to extract line segments from an image, so like a much simplified contour.
The result look like this: http://iie.fing.edu.uy/~jirafa/lsd/technical-report-fig14.html

I contacted the author, and he has told me for this he was using the "swing GUI kit" and that I would need to change it to use Processing's GUI calls.
...im assuming thats refering to the GUI.java ?

GoToLoop

... and he has told me for this he was using the "swing GUI kit"...

So this library isn't compatible w/ Processing, b/c direct access to Swing conflicts w/ Processing's own Swing access.

The library needs to be re-written so it calls Processing's API rather than Java's Swing direct access.

daddydean

@GoToLoop
Aw man, I figured.
Ok...so I would be changing the GUI.java right?
How can I call Processing's API instead of swing ?

import javax.swing.*;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.HashSet;
import java.awt.*;
import java.awt.image.*;
import javax.swing.*;



public class GUI extends JFrame {


    GUI() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


        try {
            BufferedImage myPicture = ImageIO.read(new File("piet.jpg"));
             Graphics2D g2d = myPicture.createGraphics();
            int x = myPicture.getWidth();
            int y = myPicture.getHeight();

            HashSet<Line> lines = new HashSet<Line>();


            double [] arr = myPicture.getData().getPixels(0,0,x,y,new double[x*y*3]);

            double [] arr2 = new double[x*y];

            System.out.println(arr.length);
            int c=0;
            for(int i = 0; i < arr.length-3; i+=3) {
                double B = arr[i];
                double G = arr[i+1];
                double R = arr[i+2];
                double level = R * 0.2126 + G * 0.7152 + B * 0.0722;
                arr2[c++] = level;
            }

            LSD lsd = new LSD();

            double [] out = lsd.lsd(arr2,x,y);

            for(int i = 0; i < lsd.n_out; i++) {
                for (int j = 0; j < 7; j++)

                lines.add(new Line(out[7 * i + 0], out[7 * i + 1],
                        out[7 * i + 2], out[7 * i + 3]));

            }

            for ( Line l : lines) {
                g2d.drawLine((int)l.x1,(int)l.y1,(int)l.x2,(int)l.y2);
            }

            JLabel picLabel = new JLabel(new ImageIcon(myPicture));
            add(picLabel);


        } catch (IOException e) {

        }

        setSize(800,800);
            setVisible(true);
    }


    public static void main(String [] args){
        new GUI();

    }


}

GoToLoop

public class GUI extends JFrame {

Processing's JAVA2D renderer already got its own instance of JFrame.
Look for past getFrame() posts: https://Forum.Processing.org/two/discussions/tagged?Tag=getframe()

GoToLoop

Also you need to learn Processing's API in order to replace those Swing direct calls:
https://Processing.org/reference/

daddydean

Cool thanks, ill see what I can do.
I did find something you did a bit back: https://forum.processing.org/two/discussion/12774/embedding-papplet-in-java-jframe

daddydean

Im a bit lost. Can you tell me what exactly does this getJframe() do? Currently im trying to do PApplet...