getid3_mp3::MPEGaudioHeaderValid

	 */
	public static function MPEGaudioHeaderBytesValid($head4, $allowBitrate15=false) {
		return self::MPEGaudioHeaderValid(self::MPEGaudioHeaderDecode($head4), false, $allowBitrate15);
	}

	/**
	 * @param array $rawarray
	 * @param bool  $echoerrors
	 * @param bool  $allowBitrate15
	 *
	 * @return bool
	 */
	public static function MPEGaudioHeaderValid($rawarray, $echoerrors=false, $allowBitrate15=false) {
		if (!isset($rawarray['synch']) || ($rawarray['synch'] & 0x0FFE) != 0x0FFE) {
			return false;
		}

		static $MPEGaudioVersionLookup;
		static $MPEGaudioLayerLookup;
		static $MPEGaudioBitrateLookup;
		static $MPEGaudioFrequencyLookup;
		static $MPEGaudioChannelModeLookup;
		static $MPEGaudioModeExtensionLookup;
		static $MPEGaudioEmphasisLookup;
		if (empty($MPEGaudioVersionLookup)) {
			$MPEGaudioVersionLookup       = self::MPEGaudioVersionArray();
			$MPEGaudioLayerLookup         = self::MPEGaudioLayerArray();
			$MPEGaudioBitrateLookup       = self::MPEGaudioBitrateArray();
			$MPEGaudioFrequencyLookup     = self::MPEGaudioFrequencyArray();
			$MPEGaudioChannelModeLookup   = self::MPEGaudioChannelModeArray();
			$MPEGaudioModeExtensionLookup = self::MPEGaudioModeExtensionArray();
			$MPEGaudioEmphasisLookup      = self::MPEGaudioEmphasisArray();
		}

		if (isset($MPEGaudioVersionLookup[$rawarray['version']])) {
			$decodedVersion = $MPEGaudioVersionLookup[$rawarray['version']];
		} else {
			echo ($echoerrors ? "\n".'invalid Version ('.$rawarray['version'].')' : '');
			return false;
		}
		if (isset($MPEGaudioLayerLookup[$rawarray['layer']])) {
			$decodedLayer = $MPEGaudioLayerLookup[$rawarray['layer']];
		} else {
			echo ($echoerrors ? "\n".'invalid Layer ('.$rawarray['layer'].')' : '');
			return false;
		}
		if (!isset($MPEGaudioBitrateLookup[$decodedVersion][$decodedLayer][$rawarray['bitrate']])) {
			echo ($echoerrors ? "\n".'invalid Bitrate ('.$rawarray['bitrate'].')' : '');
			if ($rawarray['bitrate'] == 15) {
				// known issue in LAME 3.90 - 3.93.1 where free-format has bitrate ID of 15 instead of 0
				// let it go through here otherwise file will not be identified
				if (!$allowBitrate15) {
					return false;
				}
			} else {
				return false;
			}
		}
		if (!isset($MPEGaudioFrequencyLookup[$decodedVersion][$rawarray['sample_rate']])) {
			echo ($echoerrors ? "\n".'invalid Frequency ('.$rawarray['sample_rate'].')' : '');
			return false;
		}
		if (!isset($MPEGaudioChannelModeLookup[$rawarray['channelmode']])) {
			echo ($echoerrors ? "\n".'invalid ChannelMode ('.$rawarray['channelmode'].')' : '');
			return false;
		}
		if (!isset($MPEGaudioModeExtensionLookup[$decodedLayer][$rawarray['modeextension']])) {
			echo ($echoerrors ? "\n".'invalid Mode Extension ('.$rawarray['modeextension'].')' : '');
			return false;
		}
		if (!isset($MPEGaudioEmphasisLookup[$rawarray['emphasis']])) {