org.xiph.speex

Class SpeexEncoder

java.lang.Object

org.xiph.speex.SpeexEncoder

public class SpeexEncoder
extends java.lang.Object

Main Speex Encoder class. This class encodes the given PCM 16bit samples into Speex packets.

Version:

$Revision: 1.6 $

Author:

Marc Gimpel, Wimba S.A. (mgimpel@horizonwimba.com)

Field Summary

Fields

Modifier and Type	Field and Description
private Bits	bits
private int	channels
private Encoder	encoder
private int	frameSize
private float[]	rawData
private int	sampleRate
static java.lang.String	VERSION Version of the Speex Encoder

Constructor Summary

Constructors

Constructor and Description
SpeexEncoder() Constructor

Method Summary

Modifier and Type	Method and Description
int	getChannels() Returns the number of channels.
Encoder	getEncoder() Returns the Encoder being used (Narrowband, Wideband or Ultrawideband).
int	getFrameSize() Returns the size of a frame.
int	getProcessedData(byte[] data, int offset) Pull the decoded data out into a byte array at the given offset and returns the number of bytes of encoded data just read.
int	getProcessedDataByteSize() Returns the number of bytes of encoded data ready to be read.
int	getSampleRate() Returns the sample rate.
boolean	init(int mode, int quality, int sampleRate, int channels) Initialisation
static void	mapPcm16bitLittleEndian2Float(byte[] pcm16bitBytes, int offsetInput, float[] samples, int offsetOutput, int length) Converts a 16 bit linear PCM stream (in the form of a byte array) into a floating point PCM stream (in the form of an float array).
boolean	processData(byte[] data, int offset, int len) This is where the actual encoding takes place
boolean	processData(float[] data, int numSamples) Encode an array of floats.
boolean	processData(short[] data, int offset, int numShorts) Encode an array of shorts.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VERSION

public static final java.lang.String VERSION

Version of the Speex Encoder

See Also:

Constant Field Values

encoder

private Encoder encoder

bits

private Bits bits

rawData

private float[] rawData

sampleRate

private int sampleRate

channels

private int channels

frameSize

private int frameSize

Constructor Detail

SpeexEncoder

public SpeexEncoder()

Constructor

Method Detail

init

public boolean init(int mode,
                    int quality,
                    int sampleRate,
                    int channels)

Initialisation

Parameters:

mode - the mode of the encoder (0=NB, 1=WB, 2=UWB).

quality - the quality setting of the encoder (between 0 and 10).

sampleRate - the number of samples per second.

channels - the number of audio channels (1=mono, 2=stereo, ...).

Returns:

true if initialisation successful.

getEncoder

public Encoder getEncoder()

Returns the Encoder being used (Narrowband, Wideband or Ultrawideband).

Returns:

the Encoder being used (Narrowband, Wideband or Ultrawideband).

getSampleRate

public int getSampleRate()

Returns the sample rate.

Returns:

the sample rate.

getChannels

public int getChannels()

Returns the number of channels.

Returns:

the number of channels.

getFrameSize

public int getFrameSize()

Returns the size of a frame.

Returns:

the size of a frame.

getProcessedData

public int getProcessedData(byte[] data,
                            int offset)

Pull the decoded data out into a byte array at the given offset and returns the number of bytes of encoded data just read.

Parameters:

data -

offset -

Returns:

the number of bytes of encoded data just read.

getProcessedDataByteSize

public int getProcessedDataByteSize()

Returns the number of bytes of encoded data ready to be read.

Returns:

the number of bytes of encoded data ready to be read.

processData

public boolean processData(byte[] data,
                           int offset,
                           int len)

This is where the actual encoding takes place

Parameters:

data -

offset -

len -

Returns:

true if successful.

processData

public boolean processData(short[] data,
                           int offset,
                           int numShorts)

Encode an array of shorts.

Parameters:

data -

offset -

numShorts -

Returns:

true if successful.

processData

public boolean processData(float[] data,
                           int numSamples)

Encode an array of floats.

Parameters:

data -

numSamples -

Returns:

true if successful.

mapPcm16bitLittleEndian2Float

public static void mapPcm16bitLittleEndian2Float(byte[] pcm16bitBytes,
                                                 int offsetInput,
                                                 float[] samples,
                                                 int offsetOutput,
                                                 int length)

Converts a 16 bit linear PCM stream (in the form of a byte array) into a floating point PCM stream (in the form of an float array). Here are some important details about the encoding:

• Java uses big endian for shorts and ints, and Windows uses little Endian. Therefore, shorts and ints must be read as sequences of bytes and combined with shifting operations.

Parameters:

pcm16bitBytes - - byte array of linear 16-bit PCM formated audio.

offsetInput -

samples - - float array to receive the 16-bit linear audio samples.

offsetOutput -

length -