org.xiph.speex
Class NbDecoder

java.lang.Object
  org.xiph.speex.NbCodec
      org.xiph.speex.NbDecoder

All Implemented Interfaces:

Codebook, Decoder

public class NbDecoder

extends NbCodec

implements Decoder

Narrowband Speex Decoder

Version:

$Revision: 1.6 $

Author:

Jim Lawrence, helloNetwork.com, Marc Gimpel, Wimba S.A. (marc@wimba.com)

Field Summary

private int	count_lost
protected boolean	enhanced
protected Inband	inband
private float[]	innov2
private float	last_ol_gain Tail of the buffer
private int	last_pitch
private float	last_pitch_gain Pitch of last correctly decoded frame
private float[]	pitch_gain_buf Pitch gain of last correctly decoded frame
private int	pitch_gain_buf_idx Pitch gain of last decoded frames
protected java.util.Random	random
protected Stereo	stereo

Fields inherited from class org.xiph.speex.NbCodec

awk1, awk2, awk3, bufSize, dtx_enabled, exc_gain_quant_scal1, exc_gain_quant_scal3, excBuf, excIdx, filters, first, frameSize, frmBuf, frmIdx, gamma1, gamma2, innov, interp_qlpc, interp_qlsp, lag_factor, lpc, lpc_floor, lpcSize, m_lsp, max_pitch, mem_sp, min_pitch, NB_FRAME_SIZE, NB_SUBMODE_BITS, NB_SUBMODES, nbSubframes, old_qlsp, pi_gain, pre_mem, preemph, qlsp, subframeSize, submodeID, submodes, VERY_SMALL, voc_m1, voc_m2, voc_mean, voc_offset, windowSize

Fields inherited from interface org.xiph.speex.Codebook

cdbk_nb, cdbk_nb_high1, cdbk_nb_high2, cdbk_nb_low1, cdbk_nb_low2, exc_10_16_table, exc_10_32_table, exc_20_32_table, exc_5_256_table, exc_5_64_table, exc_8_128_table, gain_cdbk_lbr, gain_cdbk_nb, h0, h1, hexc_10_32_table, hexc_table, high_lsp_cdbk, high_lsp_cdbk2, NB_CDBK_SIZE, NB_CDBK_SIZE_HIGH1, NB_CDBK_SIZE_HIGH2, NB_CDBK_SIZE_LOW1, NB_CDBK_SIZE_LOW2

Constructor Summary

NbDecoder()
Constructor

Method Summary

int	decode(Bits bits, float[] out) Decode the given input bits.
int	decodeLost(float[] out) Decode when packets are lost.
void	decodeStereo(float[] data, int frameSize) Decode the given bits to stereo.
boolean	getPerceptualEnhancement() Returns whether perceptual enhancement is enabled or disabled.
void	init(int frameSize, int subframeSize, int lpcSize, int bufSize) Initialise
void	setPerceptualEnhancement(boolean enhanced) Enables or disables perceptual enhancement.

Methods inherited from class org.xiph.speex.NbCodec

getDtx, getExc, getFrameSize, getInnov, getPiGain, nbinit

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.xiph.speex.Decoder

getDtx, getExc, getFrameSize, getInnov, getPiGain

Field Detail

innov2

private float[] innov2

count_lost

private int count_lost

last_pitch

private int last_pitch

last_pitch_gain

private float last_pitch_gain

Pitch of last correctly decoded frame

pitch_gain_buf

private float[] pitch_gain_buf

Pitch gain of last correctly decoded frame

pitch_gain_buf_idx

private int pitch_gain_buf_idx

Pitch gain of last decoded frames

last_ol_gain

private float last_ol_gain

Tail of the buffer

random

protected java.util.Random random

stereo

protected Stereo stereo

inband

protected Inband inband

enhanced

protected boolean enhanced

Constructor Detail

NbDecoder

public NbDecoder()

Constructor

Method Detail

init

public void init(int frameSize,
                 int subframeSize,
                 int lpcSize,
                 int bufSize)

Initialise

Overrides:

init in class NbCodec

Parameters:

frameSize -

subframeSize -

lpcSize -

bufSize -

decode

public int decode(Bits bits,
                  float[] out)
           throws java.io.StreamCorruptedException

Decode the given input bits.

Specified by:

decode in interface Decoder

Parameters:

bits - - Speex bits buffer.

out - - the decoded mono audio frame.

Returns:

1 if a terminator was found, 0 if not.

Throws:

java.io.StreamCorruptedException - If there is an error detected in the data stream.

decodeLost

public int decodeLost(float[] out)

Decode when packets are lost.

Parameters:

out - - the generated mono audio frame.

Returns:

0 if successful.

decodeStereo

public void decodeStereo(float[] data,
                         int frameSize)

Decode the given bits to stereo.

Specified by:

decodeStereo in interface Decoder

Parameters:

data - - float array of size 2*frameSize, that contains the mono audio samples in the first half. When the function has completed, the array will contain the interlaced stereo audio samples.

frameSize - - the size of a frame of mono audio samples.

setPerceptualEnhancement

public void setPerceptualEnhancement(boolean enhanced)

Enables or disables perceptual enhancement.

Specified by:

setPerceptualEnhancement in interface Decoder

Parameters:

enhanced -

getPerceptualEnhancement

public boolean getPerceptualEnhancement()

Returns whether perceptual enhancement is enabled or disabled.

Specified by:

getPerceptualEnhancement in interface Decoder

Returns:

whether perceptual enhancement is enabled or disabled.