/// <summary>
/// Decrypts an text hidden inside the image.
/// </summary>
/// <param name="image">The bytes of the image where the message is hidden.</param>
/// <param name="skipAlpha">Should the alpha channel remain untouched?.</param>
/// <returns>An array of bytes with the text that was hidden.</returns>
private static byte[] DecryptStringMessage(byte[] image, bool skipAlpha)
{
//Transfome bytes to bits.
BitArray imageBits = new BitArray(image);
//Get the size of the message we'll have to decrypt, at the beginning of the image.
int messageSize = DecryptionHelper.GetMessageSize(imageBits, 0, skipAlpha);
//Empty array of bits the size of the message size we just got.
BitArray messageBits = new BitArray(messageSize);
//Decrypts the message.
byte[] messageDecrypted = DecryptionHelper.GetDecryptedMessage(imageBits, messageBits,
SizeInfo.Text, skipAlpha);
return(messageDecrypted);
}
/// <summary>
/// Decrypts an image hidden inside the image.
/// </summary>
/// <param name="image">The bytes of the image where the message is hidden.</param>
/// <param name="skipAlpha">Should the alpha channel remain untouched?.</param>
/// <returns>An array of bytes with the image that was hidden.</returns>
private static byte[] DecryptImageMessage(byte[] image, bool skipAlpha)
{
//Transform bytes to bits.
BitArray imageBits = new BitArray(image);
//Get the size of the message we'll have to decrypt, at the beginning of the image.
Steganography.embeddedWidth = DecryptionHelper.GetMessageSize(imageBits, 0, skipAlpha);
Steganography.embeddedHeight = DecryptionHelper.GetMessageSize(imageBits, 24 * 8, skipAlpha);
//Empty array of bits the size of the message size we just got.
BitArray messageBits = new BitArray(Steganography.embeddedWidth * Steganography.embeddedHeight * 32);
//Decrypts the message.
byte[] messageDecrypted = DecryptionHelper.GetDecryptedMessage(imageBits, messageBits,
SizeInfo.Image, skipAlpha);
return(messageDecrypted);
}