getid3_flv

81class getid3_flv extends getid3_handler82{83	const magic = 'FLV';84 85	/**86	 * Break out of the loop if too many frames have been scanned; only scan this87	 * many if meta frame does not contain useful duration.88	 *89	 * @var int90	 */91	public $max_frames = 100000;92 93	/**94	 * @return bool95	 */96	public function Analyze() {97		$info = &$this->getid3->info;98 99		$this->fseek($info['avdataoffset']);100 101		$FLVdataLength = $info['avdataend'] - $info['avdataoffset'];102		$FLVheader = $this->fread(5);103 104		$info['fileformat'] = 'flv';105		$info['flv']['header']['signature'] =                           substr($FLVheader, 0, 3);106		$info['flv']['header']['version']   = getid3_lib::BigEndian2Int(substr($FLVheader, 3, 1));107		$TypeFlags                          = getid3_lib::BigEndian2Int(substr($FLVheader, 4, 1));108 109		if ($info['flv']['header']['signature'] != self::magic) {110			$this->error('Expecting "'.getid3_lib::PrintHexBytes(self::magic).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($info['flv']['header']['signature']).'"');111			unset($info['flv'], $info['fileformat']);112			return false;113		}114 115		$info['flv']['header']['hasAudio'] = (bool) ($TypeFlags & 0x04);116		$info['flv']['header']['hasVideo'] = (bool) ($TypeFlags & 0x01);117 118		$FrameSizeDataLength = getid3_lib::BigEndian2Int($this->fread(4));119		$FLVheaderFrameLength = 9;120		if ($FrameSizeDataLength > $FLVheaderFrameLength) {121			$this->fseek($FrameSizeDataLength - $FLVheaderFrameLength, SEEK_CUR);122		}123		$Duration = 0;124		$found_video = false;125		$found_audio = false;126		$found_meta  = false;127		$found_valid_meta_playtime = false;128		$tagParseCount = 0;129		$info['flv']['framecount'] = array('total'=>0, 'audio'=>0, 'video'=>0);130		$flv_framecount = &$info['flv']['framecount'];131		while ((($this->ftell() + 16) < $info['avdataend']) && (($tagParseCount++ <= $this->max_frames) || !$found_valid_meta_playtime))  {132			$ThisTagHeader = $this->fread(16);133 134			$PreviousTagLength = getid3_lib::BigEndian2Int(substr($ThisTagHeader,  0, 4));135			$TagType           = getid3_lib::BigEndian2Int(substr($ThisTagHeader,  4, 1));136			$DataLength        = getid3_lib::BigEndian2Int(substr($ThisTagHeader,  5, 3));137			$Timestamp         = getid3_lib::BigEndian2Int(substr($ThisTagHeader,  8, 3));138			$LastHeaderByte    = getid3_lib::BigEndian2Int(substr($ThisTagHeader, 15, 1));139			$NextOffset = $this->ftell() - 1 + $DataLength;140			if ($Timestamp > $Duration) {141				$Duration = $Timestamp;142			}143 144			$flv_framecount['total']++;145			switch ($TagType) {146				case GETID3_FLV_TAG_AUDIO:147					$flv_framecount['audio']++;148					if (!$found_audio) {149						$found_audio = true;150						$info['flv']['audio']['audioFormat']     = ($LastHeaderByte >> 4) & 0x0F;151						$info['flv']['audio']['audioRate']       = ($LastHeaderByte >> 2) & 0x03;152						$info['flv']['audio']['audioSampleSize'] = ($LastHeaderByte >> 1) & 0x01;153						$info['flv']['audio']['audioType']       =  $LastHeaderByte       & 0x01;154					}155					break;156 157				case GETID3_FLV_TAG_VIDEO:158					$flv_framecount['video']++;159					if (!$found_video) {160						$found_video = true;