Sample Size Box contains the sample count and a table giving the * size in bytes of each sample. This allows the media data itself to be * unframed. The total number of samples in the media is always indicated in the * sample count. * * There are two variants of the sample size box. The first variant has a fixed * size 32-bit field for representing the sample sizes; it permits defining a * constant size for all samples in a track. The second variant permits smaller * size fields, to save space when the sizes are varying but small. One of these * boxes must be present; the first version is preferred for maximum * compatibility. * * @category Zend * @package Zend_Media * @subpackage ISO14496 * @author Sven Vollbehr * @copyright Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com) * @license http://framework.zend.com/license/new-bsd New BSD License * @version $Id$ */ final class Zend_Media_Iso14496_Box_Stsz extends Zend_Media_Iso14496_FullBox { /** @var integer */ private $_sampleSize; /** @var Array */ private $_sampleSizeTable = array(); /** * Constructs the class with given parameters and reads box related data * from the ISO Base Media file. * * @param Zend_Io_Reader $reader The reader object. * @param Array $options The options array. */ public function __construct($reader, &$options = array()) { parent::__construct($reader, $options); $this->_sampleSize = $this->_reader->readUInt32BE(); $sampleCount = $this->_reader->readUInt32BE(); if ($this->_sampleSize == 0) { for ($i = 1; $i <= $sampleCount; $i++) { $this->_sampleSizeTable[$i] = $this->_reader->readUInt32BE(); } } } /** * Returns the default sample size. If all the samples are the same size, * this field contains that size value. If this field is set to 0, then the * samples have different sizes, and those sizes are stored in the sample * size table. * * @return integer */ public function getSampleSize() { return $this->_sampleSize; } /** * Sets the default sample size. If all the samples are the same size, * this field contains that size value. If this field is set to 0, then the * samples have different sizes, and those sizes are stored in the sample * size table. * * @param integer $sampleSize The default sample size. */ public function setSampleSize($sampleSize) { $this->_sampleSize = $sampleSize; } /** * Returns an array of sample sizes specifying the size of a sample, indexed * by its number. * * @return Array */ public function getSampleSizeTable() { return $this->_sampleSizeTable; } /** * Sets an array of sample sizes specifying the size of a sample, indexed * by its number. * * @param Array $sampleSizeTable The array of sample sizes. */ public function setSampleSizeTable($sampleSizeTable) { $this->_sampleSizeTable = $sampleSizeTable; } /** * Returns the box heap size in bytes. * * @return integer */ public function getHeapSize() { return parent::getHeapSize() + 8 + ($this->_sampleSize == 0 ? count($this->_sampleSizeTable) * 4 : 0); } /** * Writes the box data. * * @param Zend_Io_Writer $writer The writer object. * @return void */ protected function _writeData($writer) { parent::_writeData($writer); $writer->writeUInt32BE($this->_sampleSize); $writer->writeUInt32BE($entryCount = count($this->_sampleSizeTable)); if ($this->_sampleSize == 0) { for ($i = 1; $i <= $entryCount; $i++) { $writer->writeUInt32BE($this->_sampleSizeTable[$i]); } } } }