private void buttonEncode_Click(object sender, EventArgs e)
{
try
{
int key;
if (!int.TryParse(textBoxGetEncodeKey.Text, out key))
{
throw new Exception("Ошибка при вводе ключа!");
}
EncodeKey = Int32.Parse(textBoxGetEncodeKey.Text);
SteganoTransformation transformation = new SteganoTransformation();
SteganoContainer container = new SteganoContainer(ContainerForEncode);
SteganoMessage message = new SteganoMessage(InputMessage);
container.InitBlocks(8, 8);
container.InitBlueComponent(8, 8);
transformation.Encode(container, message, EncodeKey, 250);
container.InsertBlueComponent(8, 8);
container.SaveImage(8, 8, "encode_output.bmp");
MessageBox.Show("Успешно!\nФайл находится в директории:\n" + Directory.GetCurrentDirectory(), "Успех", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
catch (Exception excptn)
{
MessageBox.Show("Анта бака!\nОшибка при кодировании!\n" + excptn.Message + excptn.StackTrace, "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
public Color getMaxDifference(SteganoContainer original, SteganoContainer container)
{
// need to add different check params of containers
if (container.Image.Height != original.Image.Height ||
container.Image.Width != original.Image.Width)
{
throw new Exception("Размеры изображений не совпадают, сэмпай!");
}
byte g = Convert.ToByte(0);
byte b = Convert.ToByte(0);
byte r = Convert.ToByte(0);
byte a = Convert.ToByte(0);
for (var row = 0; row < container.Image.Height; row++)
{
for (var column = 0; column < container.Image.Width; column++)
{
Color pixelOriginal = original.Image.GetPixel((int)column, (int)row);
Color pixelContainer = container.Image.GetPixel((int)column, (int)row);
byte gBuf = (byte)(pixelOriginal.G ^ pixelContainer.G);
byte bBuf = (byte)(pixelOriginal.B ^ pixelContainer.B);
byte rBuf = (byte)(pixelOriginal.R ^ pixelContainer.R);
byte aBuf = (byte)(pixelOriginal.A ^ pixelContainer.A);
if (g < gBuf)
{
g = gBuf;
}
if (b < bBuf)
{
b = bBuf;
}
if (r < rBuf)
{
r = rBuf;
}
if (a < aBuf)
{
a = aBuf;
}
}
}
Color outputData = Color.FromArgb(a, r, g, b);
return(outputData);
}
private void buttonСalculate_Click(object sender, EventArgs e)
{
try
{
StatisticalCharacteristics statParams = new StatisticalCharacteristics();
SteganoContainer container = new SteganoContainer(_mainForm.ContainerForDecode);
SteganoContainer original = new SteganoContainer(_mainForm.ContainerForEncode);
Color maxDifference = statParams.getMaxDifference(container, original);
string maxDifferenceAlpha = Convert.ToString(maxDifference.A, 2).PadLeft(8, '0');
string maxDifferenceRed = Convert.ToString(maxDifference.R, 2).PadLeft(8, '0');
string maxDifferenceGreen = Convert.ToString(maxDifference.G, 2).PadLeft(8, '0');
string maxDifferenceBlue = Convert.ToString(maxDifference.B, 2).PadLeft(8, '0');
textBoxMaxDifference.Text = "Alpha: " + maxDifferenceAlpha + " Red: " + maxDifferenceRed + " Green: " + maxDifferenceGreen + " Blue: " + maxDifferenceBlue;
double [] pValues = new double [300];
for (double i = 0; i < 300; i++)
{
pValues[(int)i] = i;
}
var psnrValues = statParams.getPSNRValues(_mainForm.ContainerForEncode, _mainForm.InputMessage, pValues.Length,
_mainForm.EncodeKey);
for (int i = 0; i < 300; i++)
{
if (double.IsInfinity(psnrValues[i]))
{
psnrValues[i] = 0;
}
}
this.chartPSNRfromP.Series[0].Points.Clear();
for (int i = 0; i < pValues.Length; i++)
{
this.chartPSNRfromP.Series[0].Points.AddXY(pValues[i], psnrValues[i]);
}
}
catch (Exception excptn)
{
MessageBox.Show("Анта бака!\nОшибка при расчете характеристик!\n" + excptn.Message + excptn.StackTrace, "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
public double [] getPSNRValues(string original, string message, int maxP, int key)
{
double [] PSNRvalues = new double[maxP];
Parallel.For(0, maxP, ctr => {
SteganoTransformation transformation = new SteganoTransformation();
SteganoContainer originalImage = new SteganoContainer(original);
SteganoContainer container = new SteganoContainer(original);
SteganoMessage originalMessage = new SteganoMessage(message);
container.InitBlocks(8, 8);
container.InitBlueComponent(8, 8);
transformation.Encode(container, originalMessage, key, ctr);
container.InsertBlueComponent(8, 8);
container.SaveBitmap(8, 8);
double buf = getPSNR(originalImage, container);
PSNRvalues[ctr] = buf;
container.Image.Dispose();
originalImage.Image.Dispose();
});
return(PSNRvalues);
}
public double getPSNR(SteganoContainer original, SteganoContainer container)
{
double mseR = 0;
double mseG = 0;
double mseB = 0;
// Calculate mean square error of R, G, B.
for (var row = 0; row < container.Image.Height; row++)
{
for (var column = 0; column < container.Image.Width; column++)
{
mseR += Math.Pow(original.Image.GetPixel(column, (int)row).R ^ container.Image.GetPixel(column, (int)row).R, 2);
mseG += Math.Pow(original.Image.GetPixel(column, (int)row).G ^ container.Image.GetPixel(column, (int)row).G, 2);
mseB += Math.Pow(original.Image.GetPixel(column, (int)row).B ^ container.Image.GetPixel(column, (int)row).B, 2);
}
}
// Calculate final value of mean square error
double MSE = (mseR + mseG + mseB) / ((container.Image.Height * container.Image.Width) * 3);
// Calculate peak signal to noise ratio
double PSNR = 10 * Math.Log10(Math.Pow(RGBMaxValue, 2) / MSE);
return(PSNR);
}
public void Encode(SteganoContainer container, SteganoMessage steganoMessage, int key, int P)
{
if (steganoMessage.Size + 32 > container.Blocks.Count)
{
throw new Exception("Размер контейнера слишком мал, сэмпай!");
}
//Применили дкп ко всем блокам 8х8
foreach (var block in container.BlueComponent)
{
EncodeCoefficient.Add(DKP.Dkp(block));
}
Random rnd = new Random(key);
bool[] data = new bool[container.BlueComponent.Count - 32];
for (int i = 0; i < steganoMessage.DataBinaryString.Length; i++)
{
data[i] = true;
}
var distribution = Shuffle(data, rnd);
var steganoMessageLength = GetBinaryStringFromUInt32(steganoMessage.Size);
// put data about message length in blocks
for (int counter = 0; counter < 32; counter++)
{
EncodeCoefficient[counter] = DKP.CoefficientChange(EncodeCoefficient[counter],
steganoMessageLength[counter], u1, v1, u2, v2, P);
}
int marker = 32;
for (int i = 32; i < container.BlueComponent.Count; i++)
{
if (marker == steganoMessage.DataBinaryString.Length + 32)
{
break;
}
if (distribution[i - 32] == true)
{
EncodeCoefficient[i] = DKP.CoefficientChange(EncodeCoefficient[i], steganoMessage.DataBinaryString[marker - 32], u1, v1, u2, v2, P);
marker += 1;
}
else
{
continue;
}
}
foreach (var block in EncodeCoefficient)
{
EncodeCoefficientForWrite.Add(DKP.Odkp(block));
}
// change BlueComponent in container
for (var counter = 0; counter < container.BlueComponent.Count; counter++)
{
byte[,] buf = new byte[8, 8];
for (uint i = 0; i < 8; i++)
{
for (uint k = 0; k < 8; k++)
{
if (EncodeCoefficientForWrite[counter][i, k] < 0)
{
buf[i, k] = 0;
}
else if (EncodeCoefficientForWrite[counter][i, k] > 255)
{
buf[i, k] = 255;
}
else
{
buf[i, k] = (byte)Math.Round(EncodeCoefficientForWrite[counter][i, k]);
}
}
}
container.BlueComponent[counter] = buf;
}
}
public void Decode(SteganoContainer container, SteganoMessage steganoMessage, int key)
{
// Применили ДКП к блокам 8х8
foreach (var block in container.BlueComponent)
{
DecodeCoefficient.Add(DKP.Dkp(block));
}
double Abs1;
double Abs2;
string bits = ""; //временная переменная для записи сообщения
double[,] dkp_8x8; // временная переменная для одной матрицы 8на8
var steganoMessageLength = "";
for (int counter = 0; counter < 32; counter++)
{
dkp_8x8 = DecodeCoefficient[counter];
Abs1 = Math.Abs(dkp_8x8[u1, v1]);
Abs2 = Math.Abs(dkp_8x8[u2, v2]);
if (Abs1 > Abs2)
{
steganoMessageLength += "0";
}
if (Abs1 < Abs2)
{
steganoMessageLength += "1";
}
}
var steganoMessageLengthUInt32 = GetUInt32FromBinaryString(steganoMessageLength);
if (steganoMessageLengthUInt32 + 32 > container.Blocks.Count)
{
throw new Exception("Контейнер поврежден, сэмпай!");
}
Random rnd = new Random(key);
bool[] data = new bool[container.BlueComponent.Count - 32];
for (int i = 0; i < steganoMessageLengthUInt32; i++)
{
data[i] = true;
}
var distribution = Shuffle(data, rnd);
for (int k = 32; k < container.Blocks.Count; k++)
{
if (distribution[k - 32] == true)
{
dkp_8x8 = DecodeCoefficient[k];
Abs1 = Math.Abs(dkp_8x8[u1, v1]);
Abs2 = Math.Abs(dkp_8x8[u2, v2]);
if (Abs1 > Abs2)
{
bits += "0";
}
if (Abs1 < Abs2)
{
bits += "1";
}
}
else
{
continue;
}
}
steganoMessage.DataBinaryString = bits;
}