Dirac - A Video Codec
Created by the British Broadcasting Corporation.
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39 #ifndef _QUANT_CHOOSER_H_
40 #define _QUANT_CHOOSER_H_
int m_bottom_idx
The smallest quantisation index being tested.
Definition: quant_chooser.h:93
Class encapsulating all the metadata relating to a wavelet subband.
Definition: wavelet_utils.h:139
Choose a quantiser.
Definition: quant_chooser.h:52
int CoeffType
Type of wavelet coefficient data (should be larger than ValueType)
Definition: common.h:74
void LagrangianCalc()
Having got statistics, calculate the Lagrangian costs.
OneDArray< int > m_countNEG
An array used to count the number of negative values.
Definition: quant_chooser.h:118
Definition of class SequenceHeaderByteIO.
Definition: accessunit_byteio.h:51
int m_index_step
The step we use in jumping through the list of quantisers.
Definition: quant_chooser.h:97
A class for wavelet coefficient data.
Definition: wavelet_utils.h:622
Class for encapsulating metadata concerning a block of coefficients in a subband.
Definition: wavelet_utils.h:59
OneDArray< CostType > m_costs
An array used to collate the computed costs.
Definition: quant_chooser.h:122
void IntegralErrorCalc(Subband &node, const int xratio, const int yratio)
Calculate errors and entropies for integral-bit quantisers.
CoeffType BlockAbsMax(const Subband &node)
void SelectBestQuant()
Select the best quantisation index on the basis of the Lagrangian calculations.
QuantChooser & operator=(const QuantChooser &rhs)
Assignment = is private and body-less. This class should not be assigned.
const float m_lambda
The lambda value to be used in the Lagrangian calculation.
Definition: quant_chooser.h:106
int m_top_idx
The largest quantisation index being tested.
Definition: quant_chooser.h:95
void SetSkip(CodeBlock &cblock, const int qidx)
Set the skip flag for a codeblock.
OneDArray< double > m_error_total
An array used to collate the sum of the perceptually-weighted errors.
Definition: quant_chooser.h:120
int m_count1
The number of ones (equal to the number of coefficients)
Definition: quant_chooser.h:114
void NonIntegralErrorCalc(Subband &node, const int xratio, const int yratio)
Calculate errors and entropies for non-integral-bit quantisers.
const CoeffArray & m_coeff_data
A local reference to the data under consideration.
Definition: quant_chooser.h:103
OneDArray< int > m_count0
An array used to count the number of zeroes.
Definition: quant_chooser.h:112
void SetEntropyCorrection(const float ecfac)
Sets the factor used for correcting the entropy calculation.
Definition: quant_chooser.h:63
QuantChooser(const CoeffArray &pic_data, const float lambda)
Constructor.
float m_entropy_correctionfactor
A value for correcting the crude calculation of the entropy.
Definition: quant_chooser.h:109
int m_min_idx
The index of the quantiser with the lowest cost.
Definition: quant_chooser.h:100
int GetBestQuant(Subband &node)
Finds the best quantisers for the subband, returning the predicted number of bits needed.
float m_subband_wt
The perceptual weighting factor of the subband being tested.
Definition: quant_chooser.h:90
OneDArray< int > m_countPOS
An array used to count the number of positive values.
Definition: quant_chooser.h:116
© 2004 British Broadcasting Corporation.
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