LAMEHeader (Beaglebuddy Software's MP3 Library Documentation)

java.lang.Object
- com.beaglebuddy.mpeg.LAMEHeader

```
public class LAMEHeader
extends java.lang.Object
```
The LAME header is an extension of the Xing header and is found in variable bit rate encoded .mp3 files. It is an optional header, and if present, will be found within the first MPEG audio frame directly following the Xing header.

When the LAME header was first added in the LAME 3.12 encoder, it consisted of 20 bytes, with only the first 9 bytes being used for a version string. In LAME 3.90, the lame tag was expanded to include additional information, and expanded again in version 3.94. It is in version 3.94 that the Lame encoder started adding the Xing/LAME headers to constant bit rate encoded .mp3s, albeit with the Xing header id being set to "Info" instead of "Xing". All of this is explained in the VBR header and LAME tag article.

See Also:
official LAME Header Format, LAME Header Format, VBRI, XING, and LAME headers

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`HEADER_MAX_SIZE` LAME headers after version 3.90 were 36 bytes long
`static int`	`HEADER_MIN_SIZE` LAME headers prior to version 3.90 were 20 bytes long

Constructor Summary

Constructors
Constructor and Description
`LAMEHeader()` default constructor.
`LAMEHeader(byte[] bytes, int index)` constructor.
`LAMEHeader(java.io.InputStream inputStream)` constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`int`	`getAthType()` get the ATH type.
`ReplayGain`	`getAudiophileReplayGain()` get the gain (volume) setting specified by the user for playing the .mp3 file.
`int`	`getBitrate()` get the bit rate used to encode the .mp3 file.
`byte[]`	`getCRC()` get the 16 bit CRC value of the first 190 bytes of the Info header frame.
`int`	`getEncodingDelay()` get the number of samples of silence added to the begining of the .mp3 file
`int`	`getEncodingPadding()` get the number of samples of silence added to the end of the .mp3 file
`java.lang.String`	`getId()` get the LAME header id;
`int`	`getLowpassFilterFrequency()` get the low pass filter frequency (in hz) setting used by the LAME encoder to encode the .mp3 file.
`byte`	`getMp3Gain()` get the gain byte used by tools like mp3 Gain to normalize volumes for mp3's.
`byte[]`	`getMusicCRC()` get the 16 bit CRC value of the complete .mp3 music data as originally made by LAME.
`int`	`getMusicLength()` get length (in bytes) from the LAME header to the last byte of the last mpeg audio frame.
`int`	`getNoiseShaping()` get type of noise shaping used to encode the .mp3 file.
`float`	`getPeakSignalAmplitude()` get the peak signal amplitude that occurs in the digital audio samples in this frame.
`int`	`getPreset()` get the preset used internally by the LAME encoder/decoder as an index into an internal LAME preset enum.
`ReplayGain`	`getRadioReplayGain()` get the gain (volume) setting specified for playing the .mp3 file on the radio.
`int`	`getRevision()` get the LAME header revision;
`int`	`getSize()` gets the size (in bytes) of the LAME header.
`SourceFrequency`	`getSourceSampleFrequency()` get the original audio source's sample frequency (in hz).
`StereoMode`	`getStereoMode()` get the stereo mode used to encode the .mp3 file.
`SurroundInfo`	`getSurroundInfo()` get the surround info.
`VBRMethod`	`getVBRMethod()` get the bit rate encoding method used to encode the .mp3 file.
`Version`	`getVersion()` get the LAME header version;
`java.lang.String`	`toString()` get a string representation of the LAME header.
`boolean`	`usedNoGapNext()` get whether the .mp3 file was encoded by the LAME encoder with the --nogap option.
`boolean`	`usedNoGapPrevious()` get whether the .mp3 file was encoded by the LAME encoder with the --nogap option.
`boolean`	`usedPsytune()` get whether the .mp3 file was encoded by the LAME encoder with the --nspsytune option.
`boolean`	`usedSafejoint()` get whether the .mp3 file was encoded by the LAME encoder with the --nssafejoint option.
`boolean`	`usedUnwise()` get whether the user used some settings which would likely damage quality in normal circumstances.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - HEADER_MIN_SIZE
```
public static final int HEADER_MIN_SIZE
```
    LAME headers prior to version 3.90 were 20 bytes long
    
    See Also:
    Constant Field Values
  - HEADER_MAX_SIZE
```
public static final int HEADER_MAX_SIZE
```
    LAME headers after version 3.90 were 36 bytes long
    
    See Also:
    Constant Field Values
- Constructor Detail
  - LAMEHeader
```
public LAMEHeader()
```
    default constructor.
  - LAMEHeader
```
public LAMEHeader(java.io.InputStream inputStream)
           throws java.io.IOException,
                  ParseException
```
    constructor.
    
    Parameters:
    inputStream - input stream pointing to the LAME header in an mpeg audio frame in an .mp3 file.
    
    Throws:
    
    java.io.IOException - if there is an error while reading the LAME header from the .mp3 file.
    
    ParseException - if an invalid value is detected while parsing the LAME header's raw bytes.
  - LAMEHeader
```
public LAMEHeader(byte[] bytes,
          int index)
           throws ParseException
```
    constructor.
    
    Parameters:
    bytes - the raw bytes of an MPEG audio frame.
    index - the offset into the bytes of the MPEG audio frame where the LAME header begins.
    
    Throws:
    
    ParseException - if an invalid value is detected while parsing the LAME header's raw bytes.
- Method Detail
  - getId
```
public java.lang.String getId()
```
    get the LAME header id;
    
    Returns:
    the LAME header id;
  - getVersion
```
public Version getVersion()
```
    get the LAME header version;
    
    Returns:
    the LAME header version;
  - getRevision
```
public int getRevision()
```
    get the LAME header revision;
    
    Returns:
    the LAME header revision;
  - getVBRMethod
```
public VBRMethod getVBRMethod()
```
    get the bit rate encoding method used to encode the .mp3 file.
    
    Returns:
    the bit rate encoding method used to encode the .mp3 file.
  - getLowpassFilterFrequency
```
public int getLowpassFilterFrequency()
```
    get the low pass filter frequency (in hz) setting used by the LAME encoder to encode the .mp3 file.
    
    Returns:
    the low pass filter frequency (in hz) setting used by the LAME encoder to encode the .mp3 file.
  - getPeakSignalAmplitude
```
public float getPeakSignalAmplitude()
```
    get the peak signal amplitude that occurs in the digital audio samples in this frame.
    
    Returns:
    the LAME header peak signal amplitude;
  - getRadioReplayGain
```
public ReplayGain getRadioReplayGain()
```
    get the gain (volume) setting specified for playing the .mp3 file on the radio.
    
    Returns:
    the gain (volume) setting specified for playing the .mp3 file on the radio.
  - getAudiophileReplayGain
```
public ReplayGain getAudiophileReplayGain()
```
    get the gain (volume) setting specified by the user for playing the .mp3 file.
    
    Returns:
    the gain (volume) setting specified by the user for playing the .mp3 file.
  - getAthType
```
public int getAthType()
```
    get the ATH type.
    
    Returns:
    the ATH type.
  - usedPsytune
```
public boolean usedPsytune()
```
    get whether the .mp3 file was encoded by the LAME encoder with the --nspsytune option.
    
    Returns:
    whether the .mp3 file was encoded by the LAME encoder with the --nspsytune option.
  - usedSafejoint
```
public boolean usedSafejoint()
```
    get whether the .mp3 file was encoded by the LAME encoder with the --nssafejoint option.
    
    Returns:
    whether the .mp3 file was encoded by the LAME encoder with the --nssafejoint option.
  - usedNoGapNext
```
public boolean usedNoGapNext()
```
    get whether the .mp3 file was encoded by the LAME encoder with the --nogap option. This indicates that the --nogap continued to the next track.
    
    Returns:
    boolean indicating that the --nogap continued to the next track. It is true for all but the last track in a --nogap album.
  - usedNoGapPrevious
```
public boolean usedNoGapPrevious()
```
    get whether the .mp3 file was encoded by the LAME encoder with the --nogap option. This indicates that the --nogap continued to the previous track.
    
    Returns:
    boolean indicating that the --nogap continued to the previous track. It is true for all but the first track in a --nogap album.
  - getBitrate
```
public int getBitrate()
```
    get the bit rate used to encode the .mp3 file. If the .mp3 file was encoded using an ABR method, then this method will return the specified average bit rate. If the .mp3 file was encoded using a CBR method, then this method will return the actual bit rate. For a variable rate encoded .mp3 file, the minimal bitrate will returned. A value of 255 means that a bit rate of 255 or higher was used to encode the .mp3 file.
    
    Returns:
    the bit rate used to encode the .mp3 file.
  - getEncodingDelay
```
public int getEncodingDelay()
```
    get the number of samples of silence added to the begining of the .mp3 file
    
    Returns:
    the number of samples of silence used in the encoding delay.
  - getEncodingPadding
```
public int getEncodingPadding()
```
    get the number of samples of silence added to the end of the .mp3 file
    
    Returns:
    the number of samples of silence used in the encoding padding.
  - getNoiseShaping
```
public int getNoiseShaping()
```
    get type of noise shaping used to encode the .mp3 file.
    
    Returns:
    type of noise shaping used to encode the .mp3 file.
  - getStereoMode
```
public StereoMode getStereoMode()
```
    get the stereo mode used to encode the .mp3 file.
    
    Returns:
    the stereo mode used to encode the .mp3 file.
  - usedUnwise
```
public boolean usedUnwise()
```
    get whether the user used some settings which would likely damage quality in normal circumstances.
    
    Returns:
    whether the user used some settings which would likely damage quality in normal circumstances.
  - getSourceSampleFrequency
```
public SourceFrequency getSourceSampleFrequency()
```
    get the original audio source's sample frequency (in hz).
    
    Returns:
    the original audio source's sample frequency (in hz).
  - getMp3Gain
```
public byte getMp3Gain()
```
    get the gain byte used by tools like mp3 Gain to normalize volumes for mp3's.
    
    Returns:
    the gain settings used to normalize the sound of the .mp3 file.
  - getSurroundInfo
```
public SurroundInfo getSurroundInfo()
```
    get the surround info.
    
    Returns:
    the surround info.
  - getPreset
```
public int getPreset()
```
    get the preset used internally by the LAME encoder/decoder as an index into an internal LAME preset enum.
    
    Returns:
    one of the 2047 presets allowed ey the LAME encoder.
  - getMusicLength
```
public int getMusicLength()
```
    get length (in bytes) from the LAME header to the last byte of the last mpeg audio frame.
    
    Returns:
    the length (in bytes) from the LAME header to the last byte of the last mpeg audio frame.
  - getMusicCRC
```
public byte[] getMusicCRC()
```
    get the 16 bit CRC value of the complete .mp3 music data as originally made by LAME.
    
    Returns:
    the 16 bit CRC value of the complete .mp3 music data as originally made by LAME.
  - getCRC
```
public byte[] getCRC()
```
    get the 16 bit CRC value of the first 190 bytes of the Info header frame.
    
    Returns:
    the 16 bit CRC value of the first 190 bytes of the Info header frame.
  - getSize
```
public int getSize()
```
    gets the size (in bytes) of the LAME header. When the LAME header was first introduced with the LAME 3.12 encoder, it consisted of a 20-byte LAME version string. This was actually comprised of only a nine byte version string, with the remaining 11 bytes unused. In LAME 3.90, the lame tag was expanded to a 36 bytes in order to include numerous fields.
    
    Returns:
    the size of the LAME header.
  - toString
```
public java.lang.String toString()
```
    get a string representation of the LAME header.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    a string representation of the LAME header.

Class LAMEHeader

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

HEADER_MIN_SIZE

HEADER_MAX_SIZE

Constructor Detail

LAMEHeader

LAMEHeader

LAMEHeader

Method Detail

getId

getVersion

getRevision

getVBRMethod

getLowpassFilterFrequency

getPeakSignalAmplitude

getRadioReplayGain

getAudiophileReplayGain

getAthType

usedPsytune

usedSafejoint

usedNoGapNext

usedNoGapPrevious

getBitrate

getEncodingDelay

getEncodingPadding

getNoiseShaping

getStereoMode

usedUnwise

getSourceSampleFrequency

getMp3Gain

getSurroundInfo

getPreset

getMusicLength

getMusicCRC

getCRC

getSize

toString