public void HideBytesInPng(Image innocuousBmp, string outputImageFileName, byte[] hiddenBytes)
{
hiddenBytes = ByteEncryptionUtil.EncryptSalsa20(hiddenBytes, _key);
byte[] hiddenLengthBytes = BitConverter.GetBytes(hiddenBytes.Length);
byte[] hiddenCombinedBytes = PngUtils.Combine(hiddenLengthBytes, hiddenBytes);
byte[] rgbComponents = PngUtils.RgbComponentsToBytes(innocuousBmp);
byte[] encodedRgbComponents = EncodeBytes(hiddenCombinedBytes, rgbComponents);
Bitmap encodedBmp = PngUtils.ByteArrayToBitmap(encodedRgbComponents, innocuousBmp.Width, innocuousBmp.Height);
encodedBmp.Save(outputImageFileName, ImageFormat.Png);
encodedBmp.Dispose();
innocuousBmp.Dispose();
}
public byte[] ReadHiddenBytesFromPng(string imageFileName)
{
Bitmap loadedEncodedBmp = new Bitmap(imageFileName);
byte[] loadedEncodedRgbComponents = PngUtils.RgbComponentsToBytes(loadedEncodedBmp);
const int bytesInInt = 4;
byte[] loadedHiddenLengthBytes = DecodeBytes(loadedEncodedRgbComponents, 0, bytesInInt);
int loadedHiddenLength = BitConverter.ToInt32(loadedHiddenLengthBytes, 0);
byte[] loadedHiddenBytes = DecodeBytes(loadedEncodedRgbComponents, bytesInInt, loadedHiddenLength);
loadedEncodedBmp.Dispose();
return(ByteEncryptionUtil.DecryptSalsa20(loadedHiddenBytes, _key));
}
public void HideBytesInPng(Image innocuousBmp, string outputImageFileName, byte[] hiddenBytes)
{
byte[] hiddenLengthBytes = BitConverter.GetBytes(hiddenBytes.Length);
byte[] hiddenCombinedBytes = PngUtils.Combine(hiddenLengthBytes, hiddenBytes);
byte[] rgbComponents = PngUtils.RgbComponentsToBytes(innocuousBmp);
byte[] encodedRgbComponents = EncodeBytes(hiddenCombinedBytes, rgbComponents);
Bitmap encodedBmp = PngUtils.ByteArrayToBitmap(encodedRgbComponents, innocuousBmp.Width, innocuousBmp.Height);
encodedBmp.Save(outputImageFileName, ImageFormat.Png);
encodedBmp.Dispose();
innocuousBmp.Dispose();
Console.WriteLine("Saved as " + outputImageFileName);
return;
}
public byte[] ReadHiddenBytesFromPng(Image container) //image from RAM
{
Bitmap loadedEncodedBmp = container as Bitmap; //RGB bitmap from Image
byte[] loadedEncodedRgbComponents = PngUtils.RgbComponentsToBytes(loadedEncodedBmp);
loadedEncodedBmp.Dispose(); //no need dispose temp bitmap, and this can be disposed now.
const int bytesInInt = 4;
byte[] loadedHiddenLengthBytes = DecodeBytes(loadedEncodedRgbComponents, 0, bytesInInt);
int loadedHiddenLength = BitConverter.ToInt32(loadedHiddenLengthBytes, 0);
byte[] loadedHiddenBytes = DecodeBytes(loadedEncodedRgbComponents, bytesInInt, loadedHiddenLength);
return(loadedHiddenBytes);
}
public byte[] ReadHiddenBytesFromPng(string imageFileName) //pathway
{
Bitmap loadedEncodedBmp;
if ( //if dataURL
imageFileName.IndexOf("data:") != -1 &&
imageFileName.IndexOf("base64,") != -1 &&
nbpack.NBPackMain.IsBase64Encoded(imageFileName.Split(',')[1])
)
{
//create bitmap from dataURL, and save this as PNG-file to Upload folder.
var base64Data = Regex.Match(imageFileName, @"data:image/(?<type>.+?),(?<data>.+)").Groups["data"].Value;
var binData = Convert.FromBase64String(base64Data);
using (var stream = new MemoryStream(binData))
{
loadedEncodedBmp = new Bitmap(stream); //create image from dataURL
}
}
else
{
/* //loadedEncodedBmp = new Bitmap(imageFileName);
* Bitmap temp = new Bitmap(imageFileName); //file will be locked if incorrect
* loadedEncodedBmp = (Bitmap)temp.Clone(); //clone bitmap
* temp.Dispose(); //now file can be deleted.
*/
byte[] bytes = System.IO.File.ReadAllBytes(imageFileName);
System.IO.MemoryStream ms = new System.IO.MemoryStream(bytes);
//Image img = Image.FromStream(ms);
//loadedEncodedBmp = img as Bitmap;
loadedEncodedBmp = new Bitmap(ms);
}
byte[] loadedEncodedRgbComponents = PngUtils.RgbComponentsToBytes(loadedEncodedBmp);
const int bytesInInt = 4;
byte[] loadedHiddenLengthBytes = DecodeBytes(loadedEncodedRgbComponents, 0, bytesInInt);
int loadedHiddenLength = BitConverter.ToInt32(loadedHiddenLengthBytes, 0);
byte[] loadedHiddenBytes = DecodeBytes(loadedEncodedRgbComponents, bytesInInt, loadedHiddenLength);
loadedEncodedBmp.Dispose();
return(loadedHiddenBytes);
}
