2D geometric shape vertices coordinates detection

[Girish M]

I am trying to find the vertices and their coordinates for simple geometric shape using marvin-framework.

This is the code I have (based on https://stackoverflow.com/a/25223830/957057)

package com.example.marvin;
import static marvin.MarvinPluginCollection.floodfillSegmentation;
import static marvin.MarvinPluginCollection.moravec;
import static marvin.MarvinPluginCollection.scale;
import java.io.FileWriter;
import java.io.IOException;
import marvin.image.MarvinImage;
import marvin.image.MarvinSegment;
import marvin.io.MarvinImageIO;
public class ShapesExample {
private FileWriter fw = null;
    
    public ShapesExample() throws IOException{
  fw = new FileWriter("out.txt");
        
        // Scale down the image since the desired features can be extracted
        // in a lower resolution.
        MarvinImage image = MarvinImageIO.loadImage("square.png");
        scale(image.clone(), image, 269);
        // segment each object
        MarvinSegment[] objs = floodfillSegmentation(image);
        MarvinSegment seg;
        OUT("Number of objects: " + objs.length);
        
        // For each object...
        // Skip position 0 which is just the background
        for(int i=1; i<objs.length; i++){
            seg = objs[i];
            OUT("seq: " + seg);
            MarvinImage imgSeg = image.subimage(seg.x1-5, seg.y1-5, seg.width+10, seg.height+10);
            OUT("i = " + i + "/" + objs.length);
            int[][] output;
            output = moravec(imgSeg, null, 18, 1000000);
        int xcount = 0;
            for(int x = 0; x < output.length; x++) {
            OUT("x = " + xcount++ + "/" + output[x].length);
                for(int y = 0; y < output[y].length; y++) {
                OUTNONL("y = " + output[x][y] + " ");
                }
            OUT("");
            }
        }
        
        fw.close();
    }
    private void OUTNONL(String str) throws IOException {
        System.out.print(str);
    }
    private void OUT(String str) throws IOException {
    System.out.println(str);
    }
    public static void main(String[] args) throws IOException {
        new ShapesExample();
    }
}

square.png contains the shape image

This is the output I see:

Number of objects: 3
seq: {x1:97, x2:136, y1:35, y2:72, width:40, height:38, area:189}
i = 1/3
x = 0/48
y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 
.....
x = 48/48
y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 
seq: {x1:99, x2:135, y1:36, y2:71, width:37, height:36, area:1333}
i = 2/3
x = 0/46
y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 
.....
x = 46/46
y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 y = 0 

(where i is nth object detected in image, x is row, y is column)

As you can see all values are 0.

Question:

* what am i missing in getting the coordinates?

* why does it detect 3 shapes in the image?

[Gabriel Ambrósio Archanjo]

Answered at Stack Overflow:

https://stackoverflow.com/questions/52549493/2d-geometric-shape-vertices-coordinates-detection/52556292#52556292