module.audio.mp3.php

CMS系统 提供学习研究修改最好了 比流行的一些CMS简单 但是更容易理解 是帮助你学习PHPCMS系统的好东东哦

			$ThisFileInfo['audio']['sample_rate'] = $thisfile_mpeg_audio['sample_rate'];

			if ($thisfile_mpeg_audio['protection']) {
				$thisfile_mpeg_audio['crc'] = getid3_lib::BigEndian2Int(substr($headerstring, 4, 2));
			}

		}

		if ($thisfile_mpeg_audio['raw']['bitrate'] == 15) {
			// http://www.hydrogenaudio.org/?act=ST&f=16&t=9682&st=0
			$ThisFileInfo['warning'][] = 'Invalid bitrate index (15), this is a known bug in free-format MP3s encoded by LAME v3.90 - 3.93.1';
			$thisfile_mpeg_audio['raw']['bitrate'] = 0;
		}
		$thisfile_mpeg_audio['padding'] = (bool) $thisfile_mpeg_audio['raw']['padding'];
		$thisfile_mpeg_audio['bitrate'] = $MPEGaudioBitrateLookup[$thisfile_mpeg_audio['version']][$thisfile_mpeg_audio['layer']][$thisfile_mpeg_audio['raw']['bitrate']];

		if (($thisfile_mpeg_audio['bitrate'] == 'free') && ($offset == $ThisFileInfo['avdataoffset'])) {
			// only skip multiple frame check if free-format bitstream found at beginning of file
			// otherwise is quite possibly simply corrupted data
			$recursivesearch = false;
		}

		// For Layer 2 there are some combinations of bitrate and mode which are not allowed.
		if (!$FastMPEGheaderScan && ($thisfile_mpeg_audio['layer'] == '2')) {

			$ThisFileInfo['audio']['dataformat'] = 'mp2';
			switch ($thisfile_mpeg_audio['channelmode']) {

				case 'mono':
					if (($thisfile_mpeg_audio['bitrate'] == 'free') || ($thisfile_mpeg_audio['bitrate'] <= 192000)) {
						// these are ok
					} else {
						$ThisFileInfo['error'][] = $thisfile_mpeg_audio['bitrate'].'kbps not allowed in Layer 2, '.$thisfile_mpeg_audio['channelmode'].'.';
						return false;
					}
					break;

				case 'stereo':
				case 'joint stereo':
				case 'dual channel':
					if (($thisfile_mpeg_audio['bitrate'] == 'free') || ($thisfile_mpeg_audio['bitrate'] == 64000) || ($thisfile_mpeg_audio['bitrate'] >= 96000)) {
						// these are ok
					} else {
						$ThisFileInfo['error'][] = intval(round($thisfile_mpeg_audio['bitrate'] / 1000)).'kbps not allowed in Layer 2, '.$thisfile_mpeg_audio['channelmode'].'.';
						return false;
					}
					break;

			}

		}


		if ($ThisFileInfo['audio']['sample_rate'] > 0) {
			$thisfile_mpeg_audio['framelength'] = getid3_mp3::MPEGaudioFrameLength($thisfile_mpeg_audio['bitrate'], $thisfile_mpeg_audio['version'], $thisfile_mpeg_audio['layer'], (int) $thisfile_mpeg_audio['padding'], $ThisFileInfo['audio']['sample_rate']);
		}

		$nextframetestoffset = $offset + 1;
		if ($thisfile_mpeg_audio['bitrate'] != 'free') {

			$ThisFileInfo['audio']['bitrate'] = $thisfile_mpeg_audio['bitrate'];

			if (isset($thisfile_mpeg_audio['framelength'])) {
				$nextframetestoffset = $offset + $thisfile_mpeg_audio['framelength'];
			} else {
				$ThisFileInfo['error'][] = 'Frame at offset('.$offset.') is has an invalid frame length.';
				return false;
			}

		}

		$ExpectedNumberOfAudioBytes = 0;

		////////////////////////////////////////////////////////////////////////////////////
		// Variable-bitrate headers

		if (substr($headerstring, 4 + 32, 4) == 'VBRI') {
			// Fraunhofer VBR header is hardcoded 'VBRI' at offset 0x24 (36)
			// specs taken from http://minnie.tuhs.org/pipermail/mp3encoder/2001-January/001800.html

			$thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
			$thisfile_mpeg_audio['VBR_method']   = 'Fraunhofer';
			$ThisFileInfo['audio']['codec']                = 'Fraunhofer';

			$SideInfoData = substr($headerstring, 4 + 2, 32);

			$FraunhoferVBROffset = 36;

			$thisfile_mpeg_audio['VBR_encoder_version']     = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset +  4, 2)); // VbriVersion
			$thisfile_mpeg_audio['VBR_encoder_delay']       = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset +  6, 2)); // VbriDelay
			$thisfile_mpeg_audio['VBR_quality']             = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset +  8, 2)); // VbriQuality
			$thisfile_mpeg_audio['VBR_bytes']               = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 10, 4)); // VbriStreamBytes
			$thisfile_mpeg_audio['VBR_frames']              = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 14, 4)); // VbriStreamFrames
			$thisfile_mpeg_audio['VBR_seek_offsets']        = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 18, 2)); // VbriTableSize
			$thisfile_mpeg_audio['VBR_seek_scale']          = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 20, 2)); // VbriTableScale
			$thisfile_mpeg_audio['VBR_entry_bytes']         = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 22, 2)); // VbriEntryBytes
			$thisfile_mpeg_audio['VBR_entry_frames']        = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 24, 2)); // VbriEntryFrames

			$ExpectedNumberOfAudioBytes = $thisfile_mpeg_audio['VBR_bytes'];

			$previousbyteoffset = $offset;
			for ($i = 0; $i < $thisfile_mpeg_audio['VBR_seek_offsets']; $i++) {
				$Fraunhofer_OffsetN = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset, $thisfile_mpeg_audio['VBR_entry_bytes']));
				$FraunhoferVBROffset += $thisfile_mpeg_audio['VBR_entry_bytes'];
				$thisfile_mpeg_audio['VBR_offsets_relative'][$i] = ($Fraunhofer_OffsetN * $thisfile_mpeg_audio['VBR_seek_scale']);
				$thisfile_mpeg_audio['VBR_offsets_absolute'][$i] = ($Fraunhofer_OffsetN * $thisfile_mpeg_audio['VBR_seek_scale']) + $previousbyteoffset;
				$previousbyteoffset += $Fraunhofer_OffsetN;
			}


		} else {

			// Xing VBR header is hardcoded 'Xing' at a offset 0x0D (13), 0x15 (21) or 0x24 (36)
			// depending on MPEG layer and number of channels

			$VBRidOffset = getid3_mp3::XingVBRidOffset($thisfile_mpeg_audio['version'], $thisfile_mpeg_audio['channelmode']);
			$SideInfoData = substr($headerstring, 4 + 2, $VBRidOffset - 4);

			if ((substr($headerstring, $VBRidOffset, strlen('Xing')) == 'Xing') || (substr($headerstring, $VBRidOffset, strlen('Info')) == 'Info')) {
				// 'Xing' is traditional Xing VBR frame
				// 'Info' is LAME-encoded CBR (This was done to avoid CBR files to be recognized as traditional Xing VBR files by some decoders.)
				// 'Info' *can* legally be used to specify a VBR file as well, however.

				// http://www.multiweb.cz/twoinches/MP3inside.htm
				//00..03 = "Xing" or "Info"
				//04..07 = Flags:
				//  0x01  Frames Flag     set if value for number of frames in file is stored
				//  0x02  Bytes Flag      set if value for filesize in bytes is stored
				//  0x04  TOC Flag        set if values for TOC are stored
				//  0x08  VBR Scale Flag  set if values for VBR scale is stored
				//08..11  Frames: Number of frames in file (including the first Xing/Info one)
				//12..15  Bytes:  File length in Bytes
				//16..115  TOC (Table of Contents):
				//  Contains of 100 indexes (one Byte length) for easier lookup in file. Approximately solves problem with moving inside file.
				//  Each Byte has a value according this formula:
				//  (TOC[i] / 256) * fileLenInBytes
				//  So if song lasts eg. 240 sec. and you want to jump to 60. sec. (and file is 5 000 000 Bytes length) you can use:
				//  TOC[(60/240)*100] = TOC[25]
				//  and corresponding Byte in file is then approximately at:
				//  (TOC[25]/256) * 5000000
				//116..119  VBR Scale


				// should be safe to leave this at 'vbr' and let it be overriden to 'cbr' if a CBR preset/mode is used by LAME
//				if (substr($headerstring, $VBRidOffset, strlen('Info')) == 'Xing') {
					$thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
					$thisfile_mpeg_audio['VBR_method']   = 'Xing';
//				} else {
//					$ScanAsCBR = true;
//					$thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
//				}

				$thisfile_mpeg_audio['xing_flags_raw'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 4, 4));

				$thisfile_mpeg_audio['xing_flags']['frames']    = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000001);
				$thisfile_mpeg_audio['xing_flags']['bytes']     = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000002);
				$thisfile_mpeg_audio['xing_flags']['toc']       = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000004);
				$thisfile_mpeg_audio['xing_flags']['vbr_scale'] = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000008);

				if ($thisfile_mpeg_audio['xing_flags']['frames']) {
					$thisfile_mpeg_audio['VBR_frames'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset +  8, 4));
					//$thisfile_mpeg_audio['VBR_frames']--; // don't count header Xing/Info frame
				}
				if ($thisfile_mpeg_audio['xing_flags']['bytes']) {
					$thisfile_mpeg_audio['VBR_bytes']  = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 12, 4));
				}

				//if (($thisfile_mpeg_audio['bitrate'] == 'free') && !empty($thisfile_mpeg_audio['VBR_frames']) && !empty($thisfile_mpeg_audio['VBR_bytes'])) {
				if (!empty($thisfile_mpeg_audio['VBR_frames']) && !empty($thisfile_mpeg_audio['VBR_bytes'])) {

					$framelengthfloat = $thisfile_mpeg_audio['VBR_bytes'] / $thisfile_mpeg_audio['VBR_frames'];

					if ($thisfile_mpeg_audio['layer'] == '1') {
						// BitRate = (((FrameLengthInBytes / 4) - Padding) * SampleRate) / 12
						//$ThisFileInfo['audio']['bitrate'] = ((($framelengthfloat / 4) - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 12;
						$ThisFileInfo['audio']['bitrate'] = ($framelengthfloat / 4) * $thisfile_mpeg_audio['sample_rate'] * (2 / $ThisFileInfo['audio']['channels']) / 12;
					} else {
						// Bitrate = ((FrameLengthInBytes - Padding) * SampleRate) / 144
						//$ThisFileInfo['audio']['bitrate'] = (($framelengthfloat - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 144;
						$ThisFileInfo['audio']['bitrate'] = $framelengthfloat * $thisfile_mpeg_audio['sample_rate'] * (2 / $ThisFileInfo['audio']['channels']) / 144;
					}
					$thisfile_mpeg_audio['framelength'] = floor($framelengthfloat);
				}

				if ($thisfile_mpeg_audio['xing_flags']['toc']) {
					$LAMEtocData = substr($headerstring, $VBRidOffset + 16, 100);
					for ($i = 0; $i < 100; $i++) {
						$thisfile_mpeg_audio['toc'][$i] = ord($LAMEtocData{$i});
					}
				}
				if ($thisfile_mpeg_audio['xing_flags']['vbr_scale']) {
					$thisfile_mpeg_audio['VBR_scale'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 116, 4));
				}


				// http://gabriel.mp3-tech.org/mp3infotag.html
				if (substr($headerstring, $VBRidOffset + 120, 4) == 'LAME') {

					// shortcut
					$thisfile_mpeg_audio['LAME'] = array();
					$thisfile_mpeg_audio_lame    = &$thisfile_mpeg_audio['LAME'];


					$thisfile_mpeg_audio_lame['long_version']  = substr($headerstring, $VBRidOffset + 120, 20);
					$thisfile_mpeg_audio_lame['short_version'] = substr($thisfile_mpeg_audio_lame['long_version'], 0, 9);

					if ($thisfile_mpeg_audio_lame['short_version'] >= 'LAME3.90') {

						// extra 11 chars are not part of version string when LAMEtag present
						unset($thisfile_mpeg_audio_lame['long_version']);

						// It the LAME tag was only introduced in LAME v3.90
						// http://www.hydrogenaudio.org/?act=ST&f=15&t=9933

						// Offsets of various bytes in http://gabriel.mp3-tech.org/mp3infotag.html
						// are assuming a 'Xing' identifier offset of 0x24, which is the case for
						// MPEG-1 non-mono, but not for other combinations
						$LAMEtagOffsetContant = $VBRidOffset - 0x24;

						// shortcuts
						$thisfile_mpeg_audio_lame['RGAD']    = array('track'=>array(), 'album'=>array());
						$thisfile_mpeg_audio_lame_RGAD       = &$thisfile_mpeg_audio_lame['RGAD'];
						$thisfile_mpeg_audio_lame_RGAD_track = &$thisfile_mpeg_audio_lame_RGAD['track'];
						$thisfile_mpeg_audio_lame_RGAD_album = &$thisfile_mpeg_audio_lame_RGAD['album'];
						$thisfile_mpeg_audio_lame['raw'] = array();
						$thisfile_mpeg_audio_lame_raw    = &$thisfile_mpeg_audio_lame['raw'];

						// byte $9B  VBR Quality
						// This field is there to indicate a quality level, although the scale was not precised in the original Xing specifications.
						// Actually overwrites original Xing bytes
						unset($thisfile_mpeg_audio['VBR_scale']);
						$thisfile_mpeg_audio_lame['vbr_quality'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0x9B, 1));

						// bytes $9C-$A4  Encoder short VersionString
						$thisfile_mpeg_audio_lame['short_version'] = substr($headerstring, $LAMEtagOffsetContant + 0x9C, 9);

						// byte $A5  Info Tag revision + VBR method
						$LAMEtagRevisionVBRmethod = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xA5, 1));

						$thisfile_mpeg_audio_lame['tag_revision']      = ($LAMEtagRevisionVBRmethod & 0xF0) >> 4;