public static string stegoHuffmanRet(string fileName, Dictionary <char, int> frequencies)
{
string toRet = "";
List <bool> binary = new List <bool>();
List <char> chars;
chars = WordDocument.returnChars(fileName);
HuffmanTree huffTree = new HuffmanTree();
huffTree.Frequencies = frequencies;
huffTree.buildFromFrequences();
for (int i = 0; i < chars.Count; i++)
{
if (chars[i] == ' ')
{
string temp;
if (chars[i + 1] == ' ')
{
binary.Add(true);
i++;
temp = huffTree.decodeChar(true);
}
else
{
binary.Add(false);
temp = huffTree.decodeChar(false);
}
if (temp != string.Empty && temp != "\0")
{
toRet += temp;
}
if (temp == "\0")
{
break;
}
}
}
return(toRet);
}
public static Dictionary <char, int> stegoHuffman(string txt, string fileName, string newFileName)
{
List <bool> msg = new List <bool>();
HuffmanTree huffTree = new HuffmanTree();
txt += '\0';
huffTree.build(txt);
huffTree.Root.Traverse1();
List <bool> encoded = huffTree.encode(txt);
foreach (bool b in encoded)
{
msg.Add(b);
}
int noWords = WordDocument.noWords(fileName);
if (noWords - 1 < msg.Count)
{
return(null);
}
string coverString = WordDocument.returnDocument(fileName);
List <char> cover = coverString.ToCharArray().ToList();
string stegoText = "";
int j = 0;
int k = 0;
do
{
char pref = cover[k++];
if (pref == ' ')
{
if (msg[j])
{
stegoText += pref + " ";
}
else
{
stegoText += pref;
}
j++;
}
else
{
stegoText += pref;
}
} while (k < cover.Count - 1 && j < msg.Count);
if (j < msg.Count)
{
if (msg[j])
{
stegoText += " ";
}
else
{
stegoText += " ";
}
}
if (k < cover.Count - 1)
{
stegoText += coverString.Substring(k);
}
WordDocument.createWord(stegoText, newFileName);
return(huffTree.Frequencies);
}
