Position synchronisation frame delivers information to the * listener of how far into the audio stream he picked up; in effect, it states * the time offset from the first frame in the stream. There may only be one * POSS frame in each tag. * * @package php-reader * @subpackage ID3 * @author Sven Vollbehr * @author Ryan Butterfield * @copyright Copyright (c) 2008 The PHP Reader Project Workgroup * @license http://code.google.com/p/php-reader/wiki/License New BSD License * @version $Rev: 105 $ */ final class ID3_Frame_POSS extends ID3_Frame implements ID3_Timing { /** @var integer */ private $_format = ID3_Timing::MPEG_FRAMES; /** @var integer */ private $_position; /** * Constructs the class with given parameters and parses object related data. * * @param Reader $reader The reader object. * @param Array $options The options array. */ public function __construct($reader = null, &$options = array()) { parent::__construct($reader, $options); if ($reader === null) return; $this->_format = Transform::fromUInt8($this->_data[0]); $this->_position = Transform::fromUInt32BE(substr($this->_data, 1, 4)); } /** * Returns the timing format. * * @return integer */ public function getFormat() { return $this->_format; } /** * Sets the timing format. * * @see ID3_Timing * @param integer $format The timing format. */ public function setFormat($format) { $this->_format = $format; } /** * Returns the position where in the audio the listener starts to receive, * i.e. the beginning of the next frame. * * @return integer */ public function getPosition() { return $this->_position; } /** * Sets the position where in the audio the listener starts to receive, * i.e. the beginning of the next frame, using given format. * * @param integer $position The position. * @param integer $format The timing format. */ public function setPosition($position, $format = false) { $this->_position = $position; if ($format !== false) $this->_format = $format; } /** * Returns the frame raw data. * * @return string */ public function __toString() { $this->setData (Transform::toUInt8($this->_format) . Transform::toUInt32BE($this->_position)); return parent::__toString(); } }