using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DN2_Haar.src.Statitiscs
{
    class Blokovnost
    {
        // Works with gray images
        public static double Calc(string imageName)
        {

            // Read images
            Bitmap bmp = new Bitmap(imageName);
            LockBitmap lockBitmap = new LockBitmap(bmp);
            lockBitmap.LockBits();

            int M = lockBitmap.Width;
            int N = lockBitmap.Height;

            double result = 0.0;

            int maxM = (int)Math.Floor(M / 8.0);
            for (int i = 0; i < maxM; i++)
            {
                for (int j = 0; j < N; j++)
                {
                    Color c1 = lockBitmap.GetPixel(i * 8, j);
                    Color c2 = lockBitmap.GetPixel(i * 8 + 1, j);

                    result += Math.Abs(c1.R - c2.R);
                }
            }

            int maxN = (int)Math.Floor(N / 8.0);
            for (int j = 0; j < maxN; j++)
            {
                for (int i = 0; i < M; i++)
                {
                    Color c1 = lockBitmap.GetPixel(i, j * 8);
                    Color c2 = lockBitmap.GetPixel(i, j * 8 + 1);

                    result += Math.Abs(c1.R - c2.R);
                }
            }

            return result;
        }

    }
}