C:\> Rostislav Persion's Projects

.:: Bitmap Pixel Data Embedding ::.
Store secret messages inside the pixels of a BMP or PNG file




This program allows the user to store text data inside of the pixels of an image. The text data is converted to a binary number string. Then it is stored in the pixels by setting the red color channel to either an even value or an odd value. Even represents a binary 1 and odd represents a binary 0. To convert an odd to even or even to odd, a 1 is added to the red channel in a pixel.



Here is a PNG file with an encoded message...





  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Threading.Tasks;
  using System.Drawing;
   
   
   
  namespace CodeRed
  {
      class Program
      {
   
   
   
          static bool IsEven(int val)
          {
              bool ret = false;
              if (((double)val / 2) == Math.Round((double)val / 2)) { ret = true; }
              return ret;
          }
   
   
          static string BinToLetters(string bin)
          {
              string ret = "";
   
              for (int i = 0; i < bin.Length; i += 8)
              {
                  string byt = bin.Substring(i, 8);
   
                  int result = 0;
   
                  bool bit1 = false;
                  bool bit2 = false;
                  bool bit3 = false;
                  bool bit4 = false;
                  bool bit5 = false;
                  bool bit6 = false;
                  bool bit7 = false;
                  bool bit8 = false;
   
                  if (byt.Substring(0, 1) == "1") { bit1 = true; }
                  if (byt.Substring(0, 1) == "0") { bit1 = false; }
                  if (byt.Substring(1, 1) == "1") { bit2 = true; }
                  if (byt.Substring(1, 1) == "0") { bit2 = false; }
                  if (byt.Substring(2, 1) == "1") { bit3 = true; }
                  if (byt.Substring(2, 1) == "0") { bit3 = false; }
                  if (byt.Substring(3, 1) == "1") { bit4 = true; }
                  if (byt.Substring(3, 1) == "0") { bit4 = false; }
                  if (byt.Substring(4, 1) == "1") { bit5 = true; }
                  if (byt.Substring(4, 1) == "0") { bit5 = false; }
                  if (byt.Substring(5, 1) == "1") { bit6 = true; }
                  if (byt.Substring(5, 1) == "0") { bit6 = false; }
                  if (byt.Substring(6, 1) == "1") { bit7 = true; }
                  if (byt.Substring(6, 1) == "0") { bit7 = false; }
                  if (byt.Substring(7, 1) == "1") { bit8 = true; }
                  if (byt.Substring(7, 1) == "0") { bit8 = false; }
   
                  if (bit1 == true) { result += (int)Math.Pow(2, 7); }
                  if (bit2 == true) { result += (int)Math.Pow(2, 6); }
                  if (bit3 == true) { result += (int)Math.Pow(2, 5); }
                  if (bit4 == true) { result += (int)Math.Pow(2, 4); }
                  if (bit5 == true) { result += (int)Math.Pow(2, 3); }
                  if (bit6 == true) { result += (int)Math.Pow(2, 2); }
                  if (bit7 == true) { result += (int)Math.Pow(2, 1); }
                  if (bit8 == true) { result += (int)Math.Pow(2, 0); }
   
                  ret += (char)result;
              }
              return ret;
          }
   
   
   
          static string LettersToBin(string str)
          {
              string result = "";
              foreach (char chr in str)
              {
                  result += Convert.ToString(chr, 2).PadLeft(8, '0');
              }
   
              return result.Trim();
          }
   
          static void Main(string[] args)
          {
   
              while (true)
              {
   
                  Console.Clear();
                  Console.ForegroundColor = ConsoleColor.Red;
                  Console.WriteLine("(c) 2016 - ROSTISLAV PERSION - BMP/PNG IMAGE EMBEDDER");
                  Console.WriteLine();
   
                  Console.ForegroundColor = ConsoleColor.Green;
   
                  Console.Write("STORE [S] or DECODE [D] or QUIT [Q]: ");
                  string inpt = Console.ReadLine().Trim().ToUpper();
   
                  if (inpt == "Q")
                  {
                      Environment.Exit(0);
                  }
   
                  if (inpt == "S")
                  {
   
   
   
                      // USER INPUT
                      Console.WriteLine();
                      Console.Write("SOURCE BMP/PNG FILE: ");
                      string openfile = Console.ReadLine().Trim();
                      Console.Write("DESTINATION BMP/PNG FILE: ");
                      string openfile2 = Console.ReadLine().Trim();
   
                      // LOAD BITMAP
                      Bitmap bmp1 = new Bitmap(openfile);
   
                      // USER INPUT 
                      Console.Write("MESSAGE TO STORE (MAXIMUM CHARACTERS: " + (Math.Floor((double)(bmp1.Width * bmp1.Height) / 8) - 1).ToString() + "): ");
                      string message = Console.ReadLine().Trim();
                      string bin = LettersToBin(message + "|");
   
   
   
   
                      
   
   
   
   
                      // WILL IT FIT??
                      if (((bmp1.Width * bmp1.Height) / 8) < (message.Length + 1)) { Console.WriteLine("ERROR: TOO MUCH DATA."); Console.ReadLine(); break; }
   
   
                      // PREPARE IMAGE
                      for (int y = 0; y < bmp1.Height; y++)
                      {
                          for (int x = 0; x < bmp1.Width; x++)
                          {
                              Color col1 = bmp1.GetPixel(x, y);
                              int rr = col1.R;
                              int gg = col1.G;
                              int bb = col1.B;
                              if (rr == 255) { rr = 254; }
   
                              Color col2 = Color.FromArgb(rr, gg, bb);
                             
                              bmp1.SetPixel(x, y, col2);
                          }
                      }
   
   
                  
   
   
                      int cnt = -1;
   
                      for (int y = 0; y < bmp1.Height; y++)
                      {
                          for (int x = 0; x < bmp1.Width; x++)
                          {
                              cnt++;
   
                              Color col = bmp1.GetPixel(x, y);
                              Color newcol = Color.White;
   
                              if (cnt < bin.Length)
                              {
   
                                  if (bin.Substring(cnt, 1) == "0") // odd
                                  {
                                      if (IsEven(col.R)) { newcol = col; newcol = Color.FromArgb(col.R + 1, col.G, col.B); } else { newcol = col; }
                                  }
                                  if (bin.Substring(cnt, 1) == "1") // even
                                  {
                                      if (IsEven(col.R)) { newcol = col; } else { newcol = col; newcol = Color.FromArgb(col.R + 1, col.G, col.B); }
                                  }
   
                                  bmp1.SetPixel(x, y, newcol);
   
                              }
   
   
                          }
   
   
                      }
   
                      bmp1.Save(openfile2);
   
   
                      Console.ForegroundColor = ConsoleColor.Yellow;
                      Console.WriteLine();
                      Console.WriteLine("OUTPUT FILE: " + openfile2 + "\n");
                      Console.WriteLine("TEXT MESSAGE: " + message + "\n");
                      Console.WriteLine("BINARY MESSAGE: " + bin + "\n");
                      Console.WriteLine("IMAGE DATA HAS BEEN ENCODED." + "\n");
   
                      Console.ForegroundColor = ConsoleColor.White;
                      Console.WriteLine();
                      Console.WriteLine("PRESS ENTER TO GOT TO MAIN MENU...");
                      Console.ReadLine();
   
                  }
   
   
   
   
   
   
                  if (inpt == "D")
                  {
                      // USER INPUT
                      Console.WriteLine();
                      Console.Write("DECODE BMP/PNG FILE: ");
                      string openfile = Console.ReadLine().Trim();
   
   
                      // LOAD BITMAP
                      Bitmap bmp1 = new Bitmap(openfile);
   
                      // FILE SIZE
                      Console.Write("NUMBER OF CHARACTERS TO GET (MAX: " + Math.Floor((double)(bmp1.Width * bmp1.Height) / 8).ToString() + "): ");
                      int numchars = Convert.ToInt32(Console.ReadLine().Trim());
                      Console.WriteLine();
   
   
                      // WILL IT FIT??
                      if (numchars > Math.Floor((double)(bmp1.Width * bmp1.Height) / 8)) { Console.WriteLine("ERROR: NUMBER OF CGHARACTERS IS MORE THAN MAXIMUM."); Console.ReadLine(); break; }
   
   
   
   
   
                      string bin = "";
                      int cnt = 0;
   
                      for (int y = 0; y < bmp1.Height; y++)
                      {
                          for (int x = 0; x < bmp1.Width; x++)
                          {
                              cnt++;
   
                              if (cnt <= (numchars * 8))
                              {
   
                                  Color col = bmp1.GetPixel(x, y);
                                  if (IsEven(col.R)) { bin += "1"; } else { bin += "0"; }
                              }
                          }
                      }
   
                      Console.ForegroundColor = ConsoleColor.Yellow;
   
   
                      
   
                      string msgout = BinToLetters(bin) + "|";
                      msgout = msgout.Substring(0, msgout.IndexOf("|"));
                      Console.WriteLine("MESSAGE: " + msgout);
   
                      Console.ForegroundColor = ConsoleColor.White;
                      Console.WriteLine();
                      Console.WriteLine("PRESS ENTER TO GO TO MAIN MENU...");
                      Console.ReadLine();
   
   
   
                  }
   
   
   
   
   
   
   
   
   
              }
   
          }
      }
  }