CSteganos::__GetHiddenInfo

function __GetHiddenInfo()
{
	if ($this->containerType == "bmp")
	{
		$this->level = -1;


		$header = "";
		for ($i = 0; $i < 12; $i++)
			$header = chr(0);

		for ($i = 55, $j = 7, $k = 0; $i < 151; $i++)
		{
			$header[$k] = chr(ord($header[$k]) | ((ord($this->containerData[$i]) & 1) << $j));
			$j--;
			if ($j < 0)
			{
				$j = 7;
				$k++;
			}
		}

		if (!strcmp(mb_substr($header, 0, 4), "BSAW"))
		{
			sscanf(mb_substr($header, 4, 8), "%x", $this->dataSize);
			$this->level = 1;
			$this->offset = 151;
		}


		if ($this->level == -1)
		{
			$header = "";
			for ($i = 0; $i < 12; $i++)
				$header = chr(0);

			for ($i = 55, $j = 6, $k = 0; $i < 103; $i++)
			{
				$header[$k] = chr(ord($header[$k]) | ((ord($this->containerData[$i]) & 3) << $j));
				$j -= 2;
				if ($j < 0)
				{
					$j = 6;
					$k++;
				}
			}

			if (!strcmp(mb_substr($header, 0, 4), "BSAW"))
			{
				sscanf(mb_substr($header, 4, 8), "%x", $this->dataSize);
				$this->level = 2;
				$this->offset = 103;
			}
		}


		if ($this->level == -1)
		{
			$header = "";
			for ($i = 0; $i < 12; $i++)
				$header = chr(0);

			for ($i = 55, $j = 0; $i < 79; $i += 2, $j++)
			{
				for ($k = 0; $k < 2; $k++)
				{
					if ($k == 0)
						$header[$j] = chr(ord($header[$j]) | ((ord($this->containerData[$i]) & 15) << 4));
					else
						$header[$j] = chr(ord($header[$j]) | (ord($this->containerData[$i+1]) & 15));
				}
			}

			if (!strcmp(mb_substr($header, 0, 4), "BSAW"))
			{
				sscanf(mb_substr($header, 4, 8), "%x", $this->dataSize);
				$this->level = 4;
				$this->offset = 79;
			}
		}

		if ($this->level == -1)
		{
			$this->errorMessage = "The bitmap file '".$this->containerFile."' contains no encrypted data";
			return false;
		}

		$nBytes = (($this->level == 1) ? 8 : (($this->level == 2) ? 4 : 2));

		if ($this->offset + $this->dataSize * $nBytes > mb_strlen($this->containerData))
		{
			$this->errorMessage = "The container file '".$this->containerFile."' contains no encrypted data";
			return false;
		}
	}
	elseif ($this->containerType == "txt")
	{
		$endStr = strrchr($this->containerData, "r");
		if ($endStr === false || $endStr[1] != "n")
		{
			$this->errorMessage = "The container file '".$this->containerFile."' contains no encrypted data";
			return false;
		}

		$bits = mb_substr($this->containerData, mb_strlen($this->containerData) - mb_strlen($endStr) - 32, 32);
		$containerDataLength_bin = $this->__ConvertBitStringToBinary($bits);
		if ($containerDataLength_bin == false)
		{
			$this->errorMessage = "The container file '".$this->containerFile."' contains no encrypted data";
			return false;
		}

		$containerDataLength_hex = "";
		for ($i = 3; $i >= 0; $i--)
			$containerDataLength_hex .= sprintf("%02X", ord($containerDataLength_bin[$i]));
		sscanf($containerDataLength_hex, "%X", $this->offset);

		$this->dataSize = mb_strlen($this->containerData) - mb_strlen($endStr) - 32 - $this->offset;
	}

	return true;
}