Steganography of big text files.

Steganography.cs

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

namespace FearImageSteganography
{
    class Program
    {
        static void Main(string[] args)
        {
            //File.WriteAllText("out.txt",ReadImage((Bitmap)Image.FromFile("test1.png")));

            string text = File.ReadAllText("in.txt");

            Stopwatch s = new Stopwatch();
            s.Start();

            var i = MakeImage(text);

            Console.WriteLine("Optimised time :{0}ms", s.ElapsedMilliseconds);
            i.Save("testout.png");

            s.Restart();

            CreateImage(text,3638);

            Console.WriteLine("Old time :{0}ms", s.ElapsedMilliseconds);

            Console.ReadKey();
        }

        static Image MakeImage(string text)
        {
            int[] squareInts = new int[4096];
            for (int i = 0; i < squareInts.Length; i++)
            {
                squareInts[i] = (int)Math.Pow(i, 2);
            }

            int numPixels = text.Length / bytesPerPixel;
            int width = 0;
            int realPixels = 0;
            foreach (int i in squareInts)
            {
                if (numPixels <= i)
                {
                    width = Array.IndexOf(squareInts, i);
                    realPixels = i;
                    break;
                }
            }
            Console.WriteLine("Making an image of width {0} with {1} total pixels and {2} data pixels.",width,realPixels,numPixels);

            int numMissing = (realPixels - numPixels) * bytesPerPixel;
            byte[] missingFiller = new byte[numMissing];

            byte[] byteArray = Encoding.UTF8.GetBytes(text);


            byte[] outArray = new byte[byteArray.Length + missingFiller.Length];
            byteArray.CopyTo(outArray, 0);
            missingFiller.CopyTo(outArray, byteArray.Length);


            Bitmap buffer = new Bitmap(width, width);


            int index = 0;
            for (int x = 0; x < width; x++)
            {
                for (int y = 0; y < width; y++)
                {
                    byte r = outArray[index];
                    index++;
                    byte g = outArray[index];
                    index++;
                    byte b = outArray[index];
                    index++;

                    if (bytesPerPixel == 4)
                    {
                        byte a = outArray[index];
                        index++;
                        buffer.SetPixel(x, y, Color.FromArgb(a, r, g, b));
                    }
                    else
                    {
                        buffer.SetPixel(x, y, Color.FromArgb(r, g, b));
                    }
                }
            }

            Console.WriteLine("{0} bytes.", byteArray.Length);

            return buffer;
        }

        private const int bytesPerPixel = 4;
        static string ReadImage(Bitmap b)
        {
            byte[] byteArray = new byte[b.Width * b.Height * bytesPerPixel];

            int i = 0;
            for (int x = 0; x < b.Width; x++)
            {
                for (int y = 0; y < b.Height; y++)
                {
                    if (bytesPerPixel == 4)
                    {
                        byteArray[i] = b.GetPixel(x, y).A;
                        i++;
                    }
                    byteArray[i] = b.GetPixel(x, y).R;
                    i++;
                    byteArray[i] = b.GetPixel(x, y).G;
                    i++;
                    byteArray[i] = b.GetPixel(x, y).B;
                    i++;
                }
            }

            return Encoding.UTF8.GetString(byteArray);
        }

        private static Bitmap CreateImage(String inputText,int width)
        {
            Queue<Byte> queue = new Queue<Byte>(Encoding.UTF8.GetBytes(inputText));

            var image = new Bitmap(width, width);
            for (int x = 0; x < width; x++)
            {
                for (int y = 0; y < width; y++)
                {
                    if (queue.Count > 0)
                    {
                        List<Byte> colorValues = new List<Byte>(4);
                        for (int c = 0; c < 3; c++)
                        {
                            if (queue.Count > 0)
                            {
                                colorValues.Add(queue.Dequeue());
                            }
                            else
                            {
                                colorValues.Add(0);
                            }
                        }
                        var pixel = Color.FromArgb(255, colorValues[0], colorValues[1], colorValues[2]);
                        image.SetPixel(x, y, pixel);
                    }
                    else
                    {
                        image.SetPixel(x, y, Color.FromArgb(0, 0, 0, 0));
                    }
                }
            }
            return image;
        }
    }
}