public void InitializeDictionary(byte[] text, string newName)
{
for (int i = 0; i < text.Length; i++)
{
string caracter = ByteGenerator.ConvertToString(new byte[] { text[i] });
if (!alphabet.ContainsValue(caracter))
{
alphabet.Add(cont, caracter);
cont++;
}
}
string folder = @"C:\Compressions\";
string fullPath = folder + newName;
string content = "";
foreach (var item in alphabet)
{
KeyValuePair <long, string> pair = item;
content += pair.Value;
}
using (FileStream writer = new FileStream(fullPath, FileMode.OpenOrCreate))
{
byte[] ToWrite = ByteGenerator.ConvertToBytes(content);
for (int i = 0; i < ToWrite.Length; i++)
{
byte[] temp = { ToWrite[i] };
writer.Seek(0, SeekOrigin.End);
writer.Write(temp, 0, 1);
}
writer.Seek(0, SeekOrigin.End);
writer.Write(ByteGenerator.ConvertToBytes("@@@"), 0, 3);
}
}
public void decode(Node root, ref int index, BitArray str, ref string result)
{
if (root == null)
{
return;
}
if (root.Left == null && root.Right == null)
{
byte[] toStr = { root.byt };
result += ByteGenerator.ConvertToString(toStr);
return;
}
index++;
if (str[index] == false)
{
decode(root.Left, ref index, str, ref result);
}
else
{
decode(root.Right, ref index, str, ref result);
}
}
public void DecodeFile(byte[] text, string newName, string name)
{
string txt = ByteGenerator.ConvertToString(text);
string[] nodes = txt.Split("@@@");
int start = (nodes.Length - 1) * 3;
Dictionary <byte, int> freq = new Dictionary <byte, int>();
for (int i = 0; i < nodes.Length - 1; i++)
{
string val = nodes[i];
string character = "";
string integer = "";
if (int.TryParse(val[0].ToString(), out _))
{
character += val[0];
for (int j = 1; j < val.Length; j++)
{
integer += val[j];
start++;
}
}
else
{
for (int j = 0; j < val.Length; j++)
{
if (!int.TryParse(val[j].ToString(), out _))
{
character += val[j];
}
else
{
integer += val[j];
start++;
}
}
}
byte[] bt;
if (character == "NTR")
{
bt = ByteGenerator.ConvertToBytes('\n'.ToString());
}
else if (character == "NDL")
{
bt = ByteGenerator.ConvertToBytes('\r'.ToString());
}
else
{
bt = ByteGenerator.ConvertToBytes(character.ToString());
}
start += character.Length;
if (!freq.ContainsKey(bt[0]))
{
freq.Add(bt[0], Convert.ToInt32(integer));
}
}
BuildHuffman(freq);
BitArray result = ToBitArray(text.Skip(start).ToArray());
int index = -1;
string decoded = "";
while (index < result.Length - 1)
{
decode(this.root, ref index, result, ref decoded);
}
string folder = @"C:\Compressions\";
string fullPath = folder + newName;
using (StreamWriter sw = new StreamWriter(fullPath))
{
sw.Write(decoded);
}
}
public void Decompress(byte[] txt, string name)
{
string content = ByteGenerator.ConvertToString(txt);
string[] archivo = content.Split("@@@");
byte[] originalDict = ByteGenerator.ConvertToBytes(archivo[0]);
byte[] text = ByteGenerator.ConvertToBytes(archivo[1]);
int TextPosition = originalDict.Length + 3;
//contruir de nuevo el diccionario
for (int i = 0; i < originalDict.Length; i++)
{
alphabet.Add(cont, ByteGenerator.ConvertToString(new byte[] { originalDict[i] }));
cont++;
}
//empezar a descifrar
//string outText = "";
string single = "";
int newCode = 0;
byte[] oldByte = { txt[TextPosition] };
TextPosition++;
int oldCode = oldByte[0];
//string caracter = ByteGenerator.ConvertToString(oldByte);
string caracter = alphabet[oldCode];
string folder = @"C:\Decompressions\";
string fullpath = folder + name;
using (FileStream writer = new FileStream(fullpath, FileMode.OpenOrCreate))
{
byte[] byt = ByteGenerator.ConvertToBytes(caracter);
writer.Write(byt, 0, 1);
}
for (int i = TextPosition; i < txt.Length; i++)
{
byte[] byt = { txt[i] };
newCode = byt[0];
if (!alphabet.ContainsKey(newCode)) //si el codigo nuevo no está en el diccionario
{
single = alphabet[oldByte[0]];
single += caracter;
}
else
{
single = alphabet[byt[0]]; //ByteGenerator.ConvertToString(byt);
}
//outText += single;
byte[] salida;
using (FileStream writer = new FileStream(fullpath, FileMode.Append))
{
salida = ByteGenerator.ConvertToBytes(single);
writer.Write(salida, 0, salida.Length);
}
caracter = single[0].ToString();
alphabet.Add(cont, alphabet[oldByte[0]] + caracter);
cont++;
oldByte = byt;
}
}
