getid3_mp3::MPEGaudioHeaderDecode( string $Header4Bytes ): array|false

1919	public static function MPEGaudioHeaderDecode($Header4Bytes) {1920		// AAAA AAAA  AAAB BCCD  EEEE FFGH  IIJJ KLMM1921		// A - Frame sync (all bits set)1922		// B - MPEG Audio version ID1923		// C - Layer description1924		// D - Protection bit1925		// E - Bitrate index1926		// F - Sampling rate frequency index1927		// G - Padding bit1928		// H - Private bit1929		// I - Channel Mode1930		// J - Mode extension (Only if Joint stereo)1931		// K - Copyright1932		// L - Original1933		// M - Emphasis1934 1935		if (strlen($Header4Bytes) != 4) {1936			return false;1937		}1938 1939		$MPEGrawHeader = array();1940		$MPEGrawHeader['synch']         = (getid3_lib::BigEndian2Int(substr($Header4Bytes, 0, 2)) & 0xFFE0) >> 4;1941		$MPEGrawHeader['version']       = (ord($Header4Bytes[1]) & 0x18) >> 3; //    BB1942		$MPEGrawHeader['layer']         = (ord($Header4Bytes[1]) & 0x06) >> 1; //      CC1943		$MPEGrawHeader['protection']    = (ord($Header4Bytes[1]) & 0x01);      //        D1944		$MPEGrawHeader['bitrate']       = (ord($Header4Bytes[2]) & 0xF0) >> 4; // EEEE1945		$MPEGrawHeader['sample_rate']   = (ord($Header4Bytes[2]) & 0x0C) >> 2; //     FF1946		$MPEGrawHeader['padding']       = (ord($Header4Bytes[2]) & 0x02) >> 1; //       G1947		$MPEGrawHeader['private']       = (ord($Header4Bytes[2]) & 0x01);      //        H1948		$MPEGrawHeader['channelmode']   = (ord($Header4Bytes[3]) & 0xC0) >> 6; // II1949		$MPEGrawHeader['modeextension'] = (ord($Header4Bytes[3]) & 0x30) >> 4; //   JJ1950		$MPEGrawHeader['copyright']     = (ord($Header4Bytes[3]) & 0x08) >> 3; //     K1951		$MPEGrawHeader['original']      = (ord($Header4Bytes[3]) & 0x04) >> 2; //      L1952		$MPEGrawHeader['emphasis']      = (ord($Header4Bytes[3]) & 0x03);      //       MM1953 1954		return $MPEGrawHeader;1955	}