getID3::GetFileFormat( string $filedata, string $filename = '' ): mixed|false

1544	public function GetFileFormat(&$filedata, $filename='') {1545		// this function will determine the format of a file based on usually1546		// the first 2-4 bytes of the file (8 bytes for PNG, 16 bytes for JPG,1547		// and in the case of ISO CD image, 6 bytes offset 32kb from the start1548		// of the file).1549 1550		// Identify file format - loop through $format_info and detect with reg expr1551		foreach ($this->GetFileFormatArray() as $format_name => $info) {1552			// The /s switch on preg_match() forces preg_match() NOT to treat1553			// newline (0x0A) characters as special chars but do a binary match1554			if (!empty($info['pattern']) && preg_match('#'.$info['pattern'].'#s', $filedata)) {1555				$info['include'] = 'module.'.$info['group'].'.'.$info['module'].'.php';1556				return $info;1557			}1558		}1559 1560 1561		if (preg_match('#\\.mp[123a]$#i', $filename)) {1562			// Too many mp3 encoders on the market put garbage in front of mpeg files1563			// use assume format on these if format detection failed1564			$GetFileFormatArray = $this->GetFileFormatArray();1565			$info = $GetFileFormatArray['mp3'];1566			$info['include'] = 'module.'.$info['group'].'.'.$info['module'].'.php';1567			return $info;1568		} elseif (preg_match('#\\.mp[cp\\+]$#i', $filename) && preg_match('#[\x00\x01\x10\x11\x40\x41\x50\x51\x80\x81\x90\x91\xC0\xC1\xD0\xD1][\x20-37][\x00\x20\x40\x60\x80\xA0\xC0\xE0]#s', $filedata)) {1569			// old-format (SV4-SV6) Musepack header that has a very loose pattern match and could falsely match other data (e.g. corrupt mp3)1570			// only enable this pattern check if the filename ends in .mpc/mpp/mp+1571			$GetFileFormatArray = $this->GetFileFormatArray();1572			$info = $GetFileFormatArray['mpc'];1573			$info['include'] = 'module.'.$info['group'].'.'.$info['module'].'.php';1574			return $info;1575		} elseif (preg_match('#\\.cue$#i', $filename) && preg_match('#FILE "[^"]+" (BINARY|MOTOROLA|AIFF|WAVE|MP3)#', $filedata)) {1576			// there's not really a useful consistent "magic" at the beginning of .cue files to identify them1577			// so until I think of something better, just go by filename if all other format checks fail1578			// and verify there's at least one instance of "TRACK xx AUDIO" in the file1579			$GetFileFormatArray = $this->GetFileFormatArray();1580			$info = $GetFileFormatArray['cue'];1581			$info['include']   = 'module.'.$info['group'].'.'.$info['module'].'.php';1582			return $info;1583		}1584 1585		return false;1586	}