/**
* Returns the tag raw data.
*
* @return string
*/
public function __toString()
{
unset($this->_options["unsyncronisation"]);
$data = "";
foreach ($this->_frames as $frames)
foreach ($frames as $frame)
$data .= $frame;
$datalen = strlen($data);
$padlen = 0;
if (isset($this->_options["unsyncronisation"]) &&
$this->_options["unsyncronisation"] === true)
$this->_header->setFlags
($this->_header->getFlags() | ID3_Header::UNSYNCHRONISATION);
/* The tag padding is calculated as follows. If the tag can be written in
the space of the previous tag, the remaining space is used for padding.
If there is no previous tag or the new tag is bigger than the space taken
by the previous tag, the padding is calculated using the following
logaritmic equation: log(0.2(x + 10)), ranging from some 300 bytes to
almost 5000 bytes given the tag length of 0..256M. */
if ($this->hasFooter() === false) {
if ($this->_reader !== null && $datalen < $this->_header->getSize())
$padlen = $this->_header->getSize() - $datalen;
else
$padlen = ceil(log(0.2 * ($datalen / 1024 + 10), 10) * 1024);
}
/* ID3v2.4.0 CRC calculated w/ padding */
if (!isset($this->_options["version"]) || $this->_options["version"] >= 4)
$data = str_pad($data, $datalen + $padlen, "\0");
if ($this->hasExtendedHeader()) {
$this->_extendedHeader->setPadding($padlen);
if ($this->_extendedHeader->hasFlag(ID3_ExtendedHeader::CRC32)) {
$crc = crc32($data);
if ($crc & 0x80000000)
$crc = -(($crc ^ 0xffffffff) + 1);
$this->_extendedHeader->setCrc($crc);
}
$data = $this->getExtendedHeader() . $data;
}
/* ID3v2.3.0 CRC calculated w/o padding */
if (isset($this->_options["version"]) && $this->_options["version"] < 4)
$data = str_pad($data, $datalen + $padlen, "\0");
$this->_header->setSize(strlen($data));
return "ID3" . $this->_header . $data .
($this->hasFooter() ? "3DI" . $this->getFooter() : "");
}
