RGB to HSV Conversion

Input: RGB
Output: HSV

Steps:
1. Input RGB.

2. Normalize the RGB values to be in the range [0, 1].
    r = R/255, g = G/255, b = B/255
3. Find the difference between max and min values.
    M = max(r,g,b), m = min(r,g,b). And, the difference Δ = M - m
4. Calculate hue H.
    If M = m = 0, then H = 0
    If M = r, then compute H = (60 * ((g – b) / Δ) + 360) % 360
    If M = g, then compute H = (60 * ((b – r) / Δ) + 120) % 360
    If M = b, then compute H = (60 * ((r – g) / Δ) + 240) % 360
5. Calculate saturation S.
    If Δ = 0, S = 0; Else, S = Δ/M
6. Calculate value V.
    V = max(r,g,b)
7. Output HSV.

Software Engineering (SE) Notes

Excerpt from "Software Engineering" 10th GLOBAL Edition by Ian Sommerville

Java Program - Mid-Point Circle Drawing Algorithm

import java.awt.*;

import javax.swing.JFrame;

import java.util.Scanner;

import java.lang.*;

public class MP_CIRCLE extends Canvas

{

  static int xc,yc,r;

  

  MP_CIRCLE(int xc,int yc,int r)

  {

   this.xc=xc;

   this.yc=yc;

   this.r=r;

  }

  

  public void paint(Graphics g)

  {

   int x,y,p;

   x=0;

   y=r;

   fill(g,x,y,xc,yc);

   p=1-r;

   while(x<y)

   {

    x=x+1;

    if(p<0)

    {

     p=p+2*x+1;

    }

    else

    {

     y=y-1;

     p=p+2*x+1-2*y;

    }

    fill(g,x,y,xc,yc);

   }

  }

  

  public void fill(Graphics g,int x,int y,int xc,int yc)
  {

   g.fillOval(xc+x,yc+y,5,5);

   g.fillOval(xc+x,yc-y,5,5);

   g.fillOval(xc-x,yc+y,5,5);

   g.fillOval(xc-x,yc-y,5,5);

   g.fillOval(xc+y,yc+x,5,5);

   g.fillOval(xc+y,yc-x,5,5);

   g.fillOval(xc-y,yc+x,5,5);

   g.fillOval(xc-y,yc-x,5,5);

  }

  public static void main(String args[])

  {

   Scanner sc=new Scanner(System.in);

   System.out.println("Enter center (xc,yc): ");

   int xc=sc.nextInt();

   int yc=sc.nextInt();

   System.out.println("Enter radius r: ");

   int r=sc.nextInt();

   MP_CIRCLE c = new MP_CIRCLE(xc,yc,r);

   JFrame f=new JFrame();

   f.add(c);

   f.setSize(800,800);

   f.setVisible(true);

  }

}