com.beaglebuddy.mpeg

Class VBRIHeader

java.lang.Object

com.beaglebuddy.mpeg.VBRIHeader

public class VBRIHeader
extends java.lang.Object

A VBRI header is found in variable bit rate encoded .mp3 files that were encoded using the Fraunhofer encoder. The VBRI header is an optional header, and if present, will be found within the first MPEG audio frame directly following the MPEG side information. It is mutually exclusive with the Xing and LAME headers. That is, if an Xing or Xing/LAME header is found in the first MPEG audio frame, then a VBRI header can not occur and vice versa. If a VBRI header is found in the first MPEG audio frame, then neither an Xing or LAME header can be present. The format of a variable bit rate encoded .mp3 file is shown below.

See Also:

VBRI Header

Field Summary

Fields

Modifier and Type	Field and Description
static int	HEADER_MIN_SIZE VBRI headers are at least 26 bytes long

Constructor Summary

Constructors

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

Method Summary

Methods

Modifier and Type	Method and Description
int	getDelay() gets the delay?
java.lang.String	getId() gets the VBRI header id which is always "VBRI".
int	getNumBytes() gets the number of bytes in the .mp3 file.
int	getNumFrames() gets the number of mpeg audio frames in the .mp3 file.
int	getNumTOCEntries() gets the number of entries in the table of contents.
int	getQuality() gets the quality value, which has a range of [0 - 100], where 0 is the best and 100 is the worst.
int	getSize() gets the size (in bytes) of the VBRI header.
byte[][]	getTableOfContents() gets the table of contents, which specifies entries used for seeking mpeg audio frames within the .mp3 file.
int	getTOCEntryNumFrames() gets the number of frames per entry in the table of contents.
int	getTOCEntryScaleFactor() gets the scale factor for the entries in the table of contents.
int	getTOCEntrySize() gets the size of each entry in the table of contents.
int	getVersion() gets the VBRI header version.
java.lang.String	toString()

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

VBRI headers are at least 26 bytes long

See Also:

Constant Field Values

Constructor Detail

VBRIHeader

public VBRIHeader()

default constructor.

VBRIHeader

public VBRIHeader(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 VBRI header begins.

Throws:

ParseException - if an invalid value is detected while parsing the VBRI header's raw bytes.

VBRIHeader

public VBRIHeader(byte[] bytes,
          java.io.InputStream inputStream)
           throws java.io.IOException,
                  ParseException

constructor.

Parameters:

bytes - bytes read in from the previous attempt to find the Xing header.

inputStream - input stream pointing to the VBRI header in an mpeg audio frame in an .mp3 file.

Throws:

java.io.IOException - if there is an error while reading the VBRI header from the .mp3 file.

ParseException - if an invalid value is detected while parsing the VBRI header's raw bytes.

Method Detail

getSize

public int getSize()

gets the size (in bytes) of the VBRI header.

Returns:

the size (in bytes) of the VBRI header.

getId

public java.lang.String getId()

gets the VBRI header id which is always "VBRI".

Returns:

the VBRI header id.

getVersion

public int getVersion()

gets the VBRI header version.

Returns:

the VBRI header version.

getDelay

public int getDelay()

gets the delay?

Returns:

the delay of the mpeg audio frame.

getQuality

public int getQuality()

gets the quality value, which has a range of [0 - 100], where 0 is the best and 100 is the worst.

Returns:

the quality of the mpeg audio frame.

getNumBytes

public int getNumBytes()

gets the number of bytes in the .mp3 file.

Returns:

the number of bytes in the .mp3 file.

getNumFrames

public int getNumFrames()

gets the number of mpeg audio frames in the .mp3 file.

Returns:

the number of mpeg audio frames in the .mp3 file.

getNumTOCEntries

public int getNumTOCEntries()

gets the number of entries in the table of contents.

Returns:

the number of entries in the table of contents.

getTOCEntryScaleFactor

public int getTOCEntryScaleFactor()

gets the scale factor for the entries in the table of contents.

Returns:

the scale factor for the entries in the table of contents.

getTOCEntrySize

public int getTOCEntrySize()

gets the size of each entry in the table of contents.

Returns:

the size of each entry in the table of contents.

getTOCEntryNumFrames

public int getTOCEntryNumFrames()

gets the number of frames per entry in the table of contents.

Returns:

the number of frames per entry in the table of contents.

getTableOfContents

public byte[][] getTableOfContents()

gets the table of contents, which specifies entries used for seeking mpeg audio frames within the .mp3 file.

Returns:

the table of contents used for seeking mpeg audio frames within the .mp3 file.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

a string representation of the VBRI header.