jj2000.j2k.wavelet.synthesis

Class SynWTFilterFloatLift9x7

java.lang.Object

jj2000.j2k.wavelet.synthesis.SynWTFilter

jj2000.j2k.wavelet.synthesis.SynWTFilterFloat

jj2000.j2k.wavelet.synthesis.SynWTFilterFloatLift9x7

All Implemented Interfaces:

Markers, WaveletFilter

public class SynWTFilterFloatLift9x7
extends SynWTFilterFloat

This class inherits from the synthesis wavelet filter definition for int data. It implements the inverse wavelet transform specifically for the 9x7 filter. The implementation is based on the lifting scheme.

See the SynWTFilter class for details such as normalization, how to split odd-length signals, etc. In particular, this method assumes that the low-pass coefficient is computed first.

See Also:

SynWTFilter, SynWTFilterFloat

Field Summary

Fields

Modifier and Type	Field and Description
static float	ALPHA The value of the first lifting step coefficient
static float	BETA The value of the second lifting step coefficient
static float	DELTA The value of the fourth lifting step coefficient
static float	GAMMA The value of the third lifting step coefficient
static float	KH The value of the high-pass subband normalization factor
static float	KL The value of the low-pass subband normalization factor

Fields inherited from interface jj2000.j2k.wavelet.WaveletFilter

WT_FILTER_FLOAT_CONVOL, WT_FILTER_FLOAT_LIFT, WT_FILTER_INT_LIFT

Fields inherited from interface jj2000.j2k.codestream.Markers

COC, COD, COM, CRG, EOC, EPH, EPH_LENGTH, ERS_SEG_SYMBOLS, ERS_SOP, MAX_COMP_BITDEPTH, MAX_LPPM, MAX_LPPT, PLM, PLT, POC, PPM, PPT, PRECINCT_PARTITION_DEF_SIZE, QCC, QCD, RCOM_GEN_USE, RGN, RSIZ_BASELINE, RSIZ_ER_FLAG, RSIZ_ROI, SCOX_HOR_CB_PART, SCOX_PRECINCT_PARTITION, SCOX_USE_EPH, SCOX_USE_SOP, SCOX_VER_CB_PART, SIZ, SOC, SOD, SOP, SOP_LENGTH, SOT, SQCX_EXP_MASK, SQCX_EXP_SHIFT, SQCX_GB_MSK, SQCX_GB_SHIFT, SQCX_NO_QUANTIZATION, SQCX_SCALAR_DERIVED, SQCX_SCALAR_EXPOUNDED, SRGN_IMPLICIT, SSIZ_DEPTH_BITS, TLM

Constructor Summary

Constructors

Constructor and Description
SynWTFilterFloatLift9x7()

Method Summary

Modifier and Type	Method and Description
int	getAnHighNegSupport() Returns the negative support of the high-pass analysis filter.
int	getAnHighPosSupport() Returns the positive support of the high-pass analysis filter.
int	getAnLowNegSupport() Returns the negative support of the low-pass analysis filter.
int	getAnLowPosSupport() Returns the positive support of the low-pass analysis filter.
int	getImplType() Returns the implementation type of this filter, as defined in this class, such as WT_FILTER_INT_LIFT, WT_FILTER_FLOAT_LIFT, WT_FILTER_FLOAT_CONVOL.
int	getSynHighNegSupport() Returns the negative support of the high-pass synthesis filter.
int	getSynHighPosSupport() Returns the positive support of the high-pass synthesis filter.
int	getSynLowNegSupport() Returns the negative support of the low-pass synthesis filter.
int	getSynLowPosSupport() Returns the positive support of the low-pass synthesis filter.
boolean	isReversible() Returns the reversibility of the filter.
boolean	isSameAsFullWT(int tailOvrlp, int headOvrlp, int inLen) Returns true if the wavelet filter computes or uses the same "inner" subband coefficient as the full frame wavelet transform, and false otherwise.
void	synthetize_hpf(float[] lowSig, int lowOff, int lowLen, int lowStep, float[] highSig, int highOff, int highLen, int highStep, float[] outSig, int outOff, int outStep) An implementation of the synthetize_hpf() method that works on int data, for the inverse 9x7 wavelet transform using the lifting scheme.
void	synthetize_lpf(float[] lowSig, int lowOff, int lowLen, int lowStep, float[] highSig, int highOff, int highLen, int highStep, float[] outSig, int outOff, int outStep) An implementation of the synthetize_lpf() method that works on int data, for the inverse 9x7 wavelet transform using the lifting scheme.
String	toString() Returns a string of information about the synthesis wavelet filter

Methods inherited from class jj2000.j2k.wavelet.synthesis.SynWTFilterFloat

getDataType, synthetize_hpf, synthetize_lpf

Methods inherited from class java.lang.Object

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

Field Detail

ALPHA

public static final float ALPHA

The value of the first lifting step coefficient

See Also:

Constant Field Values

BETA

public static final float BETA

The value of the second lifting step coefficient

See Also:

Constant Field Values

GAMMA

public static final float GAMMA

The value of the third lifting step coefficient

See Also:

Constant Field Values

DELTA

public static final float DELTA

The value of the fourth lifting step coefficient

See Also:

Constant Field Values

KL

public static final float KL

The value of the low-pass subband normalization factor

See Also:

Constant Field Values

KH

public static final float KH

The value of the high-pass subband normalization factor

See Also:

Constant Field Values

Constructor Detail

SynWTFilterFloatLift9x7

public SynWTFilterFloatLift9x7()

Method Detail

synthetize_lpf

public void synthetize_lpf(float[] lowSig,
                           int lowOff,
                           int lowLen,
                           int lowStep,
                           float[] highSig,
                           int highOff,
                           int highLen,
                           int highStep,
                           float[] outSig,
                           int outOff,
                           int outStep)

An implementation of the synthetize_lpf() method that works on int data, for the inverse 9x7 wavelet transform using the lifting scheme. See the general description of the synthetize_lpf() method in the SynWTFilter class for more details.

The low-pass and high-pass subbands are normalized by respectively a factor of 1/KL and a factor of 1/KH

The coefficients of the first lifting step are [-DELTA 1 -DELTA].

The coefficients of the second lifting step are [-GAMMA 1 -GAMMA].

The coefficients of the third lifting step are [-BETA 1 -BETA].

The coefficients of the fourth lifting step are [-ALPHA 1 -ALPHA].

Specified by:

synthetize_lpf in class SynWTFilterFloat

Parameters:

lowSig - This is the array that contains the low-pass input signal.

lowOff - This is the index in lowSig of the first sample to filter.

lowLen - This is the number of samples in the low-pass input signal to filter.

lowStep - This is the step, or interleave factor, of the low-pass input signal samples in the lowSig array.

highSig - This is the array that contains the high-pass input signal.

highOff - This is the index in highSig of the first sample to filter.

highLen - This is the number of samples in the high-pass input signal to filter.

highStep - This is the step, or interleave factor, of the high-pass input signal samples in the highSig array.

outSig - This is the array where the output signal is placed. It should be long enough to contain the output signal.

outOff - This is the index in outSig of the element where to put the first output sample.

outStep - This is the step, or interleave factor, of the output samples in the outSig array.

See Also:

SynWTFilter.synthetize_lpf(java.lang.Object, int, int, int, java.lang.Object, int, int, int, java.lang.Object, int, int)

synthetize_hpf

public void synthetize_hpf(float[] lowSig,
                           int lowOff,
                           int lowLen,
                           int lowStep,
                           float[] highSig,
                           int highOff,
                           int highLen,
                           int highStep,
                           float[] outSig,
                           int outOff,
                           int outStep)

An implementation of the synthetize_hpf() method that works on int data, for the inverse 9x7 wavelet transform using the lifting scheme. See the general description of the synthetize_hpf() method in the SynWTFilter class for more details.

The low-pass and high-pass subbands are normalized by respectively a factor of 1/KL and a factor of 1/KH

The coefficients of the first lifting step are [-DELTA 1 -DELTA].

The coefficients of the second lifting step are [-GAMMA 1 -GAMMA].

The coefficients of the third lifting step are [-BETA 1 -BETA].

The coefficients of the fourth lifting step are [-ALPHA 1 -ALPHA].

Specified by:

synthetize_hpf in class SynWTFilterFloat

Parameters:

lowSig - This is the array that contains the low-pass input signal.

lowOff - This is the index in lowSig of the first sample to filter.

lowLen - This is the number of samples in the low-pass input signal to filter.

lowStep - This is the step, or interleave factor, of the low-pass input signal samples in the lowSig array.

highSig - This is the array that contains the high-pass input signal.

highOff - This is the index in highSig of the first sample to filter.

highLen - This is the number of samples in the high-pass input signal to filter.

highStep - This is the step, or interleave factor, of the high-pass input signal samples in the highSig array.

outSig - This is the array where the output signal is placed. It should be long enough to contain the output signal.

outOff - This is the index in outSig of the element where to put the first output sample.

outStep - This is the step, or interleave factor, of the output samples in the outSig array.

See Also:

SynWTFilter.synthetize_hpf(java.lang.Object, int, int, int, java.lang.Object, int, int, int, java.lang.Object, int, int)

getAnLowNegSupport

public int getAnLowNegSupport()

Returns the negative support of the low-pass analysis filter. That is the number of taps of the filter in the negative direction.

Returns:

2

getAnLowPosSupport

public int getAnLowPosSupport()

Returns the positive support of the low-pass analysis filter. That is the number of taps of the filter in the negative direction.

Returns:

The number of taps of the low-pass analysis filter in the positive direction

getAnHighNegSupport

public int getAnHighNegSupport()

Returns the negative support of the high-pass analysis filter. That is the number of taps of the filter in the negative direction.

Returns:

The number of taps of the high-pass analysis filter in the negative direction

getAnHighPosSupport

public int getAnHighPosSupport()

Returns the positive support of the high-pass analysis filter. That is the number of taps of the filter in the negative direction.

Returns:

The number of taps of the high-pass analysis filter in the positive direction

getSynLowNegSupport

public int getSynLowNegSupport()

Returns the negative support of the low-pass synthesis filter. That is the number of taps of the filter in the negative direction.

A MORE PRECISE DEFINITION IS NEEDED

Returns:

The number of taps of the low-pass synthesis filter in the negative direction

getSynLowPosSupport

public int getSynLowPosSupport()

Returns the positive support of the low-pass synthesis filter. That is the number of taps of the filter in the negative direction.

A MORE PRECISE DEFINITION IS NEEDED

Returns:

The number of taps of the low-pass synthesis filter in the positive direction

getSynHighNegSupport

public int getSynHighNegSupport()

Returns the negative support of the high-pass synthesis filter. That is the number of taps of the filter in the negative direction.

A MORE PRECISE DEFINITION IS NEEDED

Returns:

The number of taps of the high-pass synthesis filter in the negative direction

getSynHighPosSupport

public int getSynHighPosSupport()

Returns the positive support of the high-pass synthesis filter. That is the number of taps of the filter in the negative direction.

A MORE PRECISE DEFINITION IS NEEDED

Returns:

The number of taps of the high-pass synthesis filter in the positive direction

getImplType

public int getImplType()

Returns the implementation type of this filter, as defined in this class, such as WT_FILTER_INT_LIFT, WT_FILTER_FLOAT_LIFT, WT_FILTER_FLOAT_CONVOL.

Returns:

WT_FILTER_INT_LIFT.

isReversible

public boolean isReversible()

Returns the reversibility of the filter. A filter is considered reversible if it is suitable for lossless coding.

Returns:

true since the 9x7 is reversible, provided the appropriate rounding is performed.

isSameAsFullWT

public boolean isSameAsFullWT(int tailOvrlp,
                              int headOvrlp,
                              int inLen)

Returns true if the wavelet filter computes or uses the same "inner" subband coefficient as the full frame wavelet transform, and false otherwise. In particular, for block based transforms with reduced overlap, this method should return false. The term "inner" indicates that this applies only with respect to the coefficient that are not affected by image boundaries processings such as symmetric extension, since there is not reference method for this.

The result depends on the length of the allowed overlap when compared to the overlap required by the wavelet filter. It also depends on how overlap processing is implemented in the wavelet filter.

Parameters:

tailOvrlp - This is the number of samples in the input signal before the first sample to filter that can be used for overlap.

headOvrlp - This is the number of samples in the input signal after the last sample to filter that can be used for overlap.

inLen - This is the lenght of the input signal to filter.The required number of samples in the input signal after the last sample depends on the length of the input signal.

Returns:

true if both overlaps are greater than 2, and correct processing is applied in the analyze() method.

toString

public String toString()

Returns a string of information about the synthesis wavelet filter

Overrides:

toString in class Object

Returns:

wavelet filter type.