corrade-vassal – Rev 1
?pathlinks?
/*
* CVS identifier:
*
* $Id: CBlkRateDistStats.java,v 1.11 2001/09/14 09:23:51 grosbois Exp $
*
* Class: CBlkRateDistStats
*
* Description: The coded (compressed) code-block with
* rate-distortion statistics.
*
*
*
* COPYRIGHT:
*
* This software module was originally developed by Raphaël Grosbois and
* Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel
* Askelöf (Ericsson Radio Systems AB); and Bertrand Berthelot, David
* Bouchard, Félix Henry, Gerard Mozelle and Patrice Onno (Canon Research
* Centre France S.A) in the course of development of the JPEG2000
* standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This
* software module is an implementation of a part of the JPEG 2000
* Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio
* Systems AB and Canon Research Centre France S.A (collectively JJ2000
* Partners) agree not to assert against ISO/IEC and users of the JPEG
* 2000 Standard (Users) any of their rights under the copyright, not
* including other intellectual property rights, for this software module
* with respect to the usage by ISO/IEC and Users of this software module
* or modifications thereof for use in hardware or software products
* claiming conformance to the JPEG 2000 Standard. Those intending to use
* this software module in hardware or software products are advised that
* their use may infringe existing patents. The original developers of
* this software module, JJ2000 Partners and ISO/IEC assume no liability
* for use of this software module or modifications thereof. No license
* or right to this software module is granted for non JPEG 2000 Standard
* conforming products. JJ2000 Partners have full right to use this
* software module for his/her own purpose, assign or donate this
* software module to any third party and to inhibit third parties from
* using this software module for non JPEG 2000 Standard conforming
* products. This copyright notice must be included in all copies or
* derivative works of this software module.
*
* Copyright (c) 1999/2000 JJ2000 Partners.
* */
using System;
using CSJ2K.j2k.wavelet.analysis;
using CSJ2K.j2k.entropy;
namespace CSJ2K.j2k.entropy.encoder
{
/// <summary> This class stores coded (compressed) code-blocks with their associated
/// rate-distortion statistics. This object should always contain all the
/// compressed data of the code-block. It is applicable to the encoder engine
/// only. Some data of the coded-block is stored in the super class, see
/// CodedCBlk.
///
/// <p>The rate-distortion statistics (i.e. R-D slope) is stored for valid
/// points only. The set of valid points is determined by the entropy coder
/// engine itself. Normally they are selected so as to lye in a convex hull,
/// which can be achived by using the 'selectConvexHull' method of this class,
/// but some other strategies might be employed.</p>
///
/// <p>The rate (in bytes) for each truncation point (valid or not) is stored
/// in the 'truncRates' array. The rate of a truncation point is the total
/// number of bytes in 'data' (see super class) that have to be decoded to
/// reach the truncation point.</p>
///
/// <p>The slope (reduction of distortion divided by the increase in rate) at
/// each of the valid truncation points is stored in 'truncSlopes'.</p>
///
/// <p>The index of each valid truncation point is stored in 'truncIdxs'. The
/// index should be interpreted in the following way: a valid truncation point
/// at position 'n' has the index 'truncIdxs[n]', the rate
/// 'truncRates[truncIdxs[n]]' and the slope 'truncSlopes[n]'. The arrays
/// 'truncIdxs' and 'truncRates' have at least 'nVldTrunc' elements. The
/// 'truncRates' array has at least 'nTotTrunc' elements.</p>
///
/// <p>In addition the 'isTermPass' array contains a flag for each truncation
/// point (valid and non-valid ones) that tells if the pass is terminated or
/// not. If this variable is null then it means that no pass is terminated,
/// except the last one which always is.</p>
///
/// <p>The compressed data is stored in the 'data' member variable of the super
/// class.</p>
///
/// </summary>
/// <seealso cref="CodedCBlk">
///
/// </seealso>
public class CBlkRateDistStats:CodedCBlk
{
/// <summary>The subband to which the code-block belongs </summary>
public SubbandAn sb;
/// <summary>The total number of truncation points </summary>
public int nTotTrunc;
/// <summary>The number of valid truncation points </summary>
public int nVldTrunc;
/// <summary>The rate (in bytes) for each truncation point (valid and non-valid
/// ones)
/// </summary>
public int[] truncRates;
/// <summary>The distortion for each truncation point (valid and non-valid ones) </summary>
public double[] truncDists;
/// <summary>The negative of the rate-distortion slope for each valid truncation
/// point
/// </summary>
public float[] truncSlopes;
/// <summary>The indices of the valid truncation points, in increasing order.</summary>
public int[] truncIdxs;
/// <summary>Array of flags indicating terminated passes (valid or non-valid
/// truncation points).
/// </summary>
public bool[] isTermPass;
/// <summary>The number of ROI coefficients in the code-block </summary>
public int nROIcoeff = 0;
/// <summary>Number of ROI coding passes </summary>
public int nROIcp = 0;
/// <summary> Creates a new CBlkRateDistStats object without allocating any space for
/// 'truncRates', 'truncSlopes', 'truncDists' and 'truncIdxs' or 'data'.
///
/// </summary>
public CBlkRateDistStats()
{
}
/// <summary> Creates a new CBlkRateDistStats object and initializes the valid
/// truncation points, their rates and their slopes, from the 'rates' and
/// 'dist' arrays. The 'rates', 'dist' and 'termp' arrays must contain the
/// rate (in bytes), the reduction in distortion (from nothing coded) and
/// the flag indicating if termination is used, respectively, for each
/// truncation point.
///
/// <p>The valid truncation points are selected by taking them as lying on
/// a convex hull. This is done by calling the method
/// selectConvexHull().</p>
///
/// <p>Note that the arrays 'rates' and 'termp' are copied, not referenced,
/// so they can be modified after a call to this constructor.</p>
///
/// </summary>
/// <param name="m">The horizontal index of the code-block, within the subband.
///
/// </param>
/// <param name="n">The vertical index of the code-block, within the subband.
///
/// </param>
/// <param name="skipMSBP">The number of skipped most significant bit-planes for
/// this code-block.
///
/// </param>
/// <param name="data">The compressed data. This array is referenced by this
/// object so it should not be modified after.
///
/// </param>
/// <param name="rates">The rates (in bytes) for each truncation point in the
/// compressed data. This array is modified by the method but no reference
/// is kept to it.
///
/// </param>
/// <param name="dists">The reduction in distortion (with respect to no
/// information coded) for each truncation point. This array is modified by
/// the method but no reference is kept to it.
///
/// </param>
/// <param name="termp">An array of boolean flags indicating, for each pass, if a
/// pass is terminated or not (true if terminated). If null then it is
/// assumed that no pass is terminated except the last one which always is.
///
/// </param>
/// <param name="np">The number of truncation points contained in 'rates', 'dist'
/// and 'termp'.
///
/// </param>
/// <param name="inclast">If false the convex hull is constructed as for lossy
/// coding. If true it is constructed as for lossless coding, in which case
/// it is ensured that all bit-planes are sent (i.e. the last truncation
/// point is always included).
///
/// </param>
public CBlkRateDistStats(int m, int n, int skipMSBP, byte[] data, int[] rates, double[] dists, bool[] termp, int np, bool inclast):base(m, n, skipMSBP, data)
{
selectConvexHull(rates, dists, termp, np, inclast);
}
/// <summary> Compute the rate-distorsion slopes and selects those that lie in a
/// convex hull. It will compute the slopes, select the ones that form the
/// convex hull and initialize the 'truncIdxs' and 'truncSlopes' arrays, as
/// well as 'nVldTrunc', with the selected truncation points. It will also
/// initialize 'truncRates' and 'isTermPass' arrays, as well as
/// 'nTotTrunc', with all the truncation points (selected or not).
///
/// <p> Note that the arrays 'rates' and 'termp' are copied, not
/// referenced, so they can be modified after a call to this method.</p>
///
/// </summary>
/// <param name="rates">The rates (in bytes) for each truncation point in the
/// compressed data. This array is modified by the method.
///
/// </param>
/// <param name="dists">The reduction in distortion (with respect to no
/// information coded) for each truncation point. This array is modified by
/// the method.
///
/// </param>
/// <param name="termp">An array of boolean flags indicating, for each pass, if a
/// pass is terminated or not (true if terminated). If null then it is
/// assumed that no pass is terminated except the last one which always is.
///
/// </param>
/// <param name="n">The number of truncation points contained in 'rates', 'dist'
/// and 'termp'.
///
/// </param>
/// <param name="inclast">If false the convex hull is constructed as for lossy
/// coding. If true it is constructed as for lossless coding, in which case
/// it is ensured that all bit-planes are sent (i.e. the last truncation
/// point is always included).
///
/// </param>
public virtual void selectConvexHull(int[] rates, double[] dists, bool[] termp, int n, bool inclast)
{
int first_pnt; // The first point containing some coded data
int p; // last selected point
int k; // current point
int i; // current valid point
int npnt; // number of selected (i.e. valid) points
int delta_rate; // Rate difference
double delta_dist; // Distortion difference
float k_slope; // R-D slope for the current point
float p_slope; // R-D slope for the last selected point
//int ll_rate; // Rate for "lossless" coding (i.e. all coded info)
// Convention: when a negative value is stored in 'rates' it meas an
// invalid point. The absolute value is always the rate for that point.
// Look for first point with some coded info (rate not 0)
first_pnt = 0;
while (first_pnt < n && rates[first_pnt] <= 0)
{
first_pnt++;
}
// Select the valid points
npnt = n - first_pnt;
p_slope = 0f; // To keep compiler happy
//UPGRADE_NOTE: Label 'ploop' was moved. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1014'"
do
{
p = - 1;
for (k = first_pnt; k < n; k++)
{
if (rates[k] < 0)
{
// Already invalidated point
continue;
}
// Calculate decrease in distortion and rate
if (p >= 0)
{
delta_rate = rates[k] - rates[p];
delta_dist = dists[k] - dists[p];
}
else
{
// This is with respect to no info coded
delta_rate = rates[k];
delta_dist = dists[k];
}
// If exactly same distortion don't eliminate if the rates are
// equal, otherwise it can lead to infinite slope in lossless
// coding.
if (delta_dist < 0f || (delta_dist == 0f && delta_rate > 0))
{
// This point increases distortion => invalidate
rates[k] = - rates[k];
npnt--;
continue; // Goto next point
}
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
k_slope = (float) (delta_dist / delta_rate);
// Check that there is a decrease in distortion, slope is not
// infinite (i.e. delta_dist is not 0) and slope is
// decreasing.
if (p >= 0 && (delta_rate <= 0 || k_slope >= p_slope))
{
// Last point was not good
rates[p] = - rates[p]; // Remove p from valid points
npnt--;
//UPGRADE_NOTE: Labeled continue statement was changed to a goto statement. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1015'"
goto ploop; // Restart from the first one
}
else
{
p_slope = k_slope;
p = k;
}
}
// If we get to last point we are done
break;
//UPGRADE_NOTE: Label 'ploop' was moved. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1014'"
ploop: ;
}
while (true); // We end the loop with the break statement
// If in lossless mode make sure we don't eliminate any last
// bit-planes from being sent.
if (inclast && n > 0 && rates[n - 1] < 0)
{
rates[n - 1] = - rates[n - 1];
// This rate can never be equal to any previous selected rate,
// given the selection algorithm above, so no problem arises of
// infinite slopes.
npnt++;
}
// Initialize the arrays of this object
nTotTrunc = n;
nVldTrunc = npnt;
truncRates = new int[n];
truncDists = new double[n];
truncSlopes = new float[npnt];
truncIdxs = new int[npnt];
if (termp != null)
{
isTermPass = new bool[n];
Array.Copy(termp, 0, isTermPass, 0, n);
}
else
{
isTermPass = null;
}
Array.Copy(rates, 0, truncRates, 0, n);
for (k = first_pnt, p = - 1, i = 0; k < n; k++)
{
if (rates[k] > 0)
{
// A valid point
truncDists[k] = dists[k];
if (p < 0)
{
// Only arrives at first valid point
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
truncSlopes[i] = (float) (dists[k] / rates[k]);
}
else
{
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
truncSlopes[i] = (float) ((dists[k] - dists[p]) / (rates[k] - rates[p]));
}
truncIdxs[i] = k;
i++;
p = k;
}
else
{
truncDists[k] = - 1;
truncRates[k] = - truncRates[k];
}
}
}
/// <summary> Returns the contents of the object in a string. This is used for
/// debugging.
///
/// </summary>
/// <returns> A string with the contents of the object
///
/// </returns>
public override System.String ToString()
{
System.String str = base.ToString() + "\n nVldTrunc=" + nVldTrunc + ", nTotTrunc=" + nTotTrunc + ", num. ROI" + " coeff=" + nROIcoeff + ", num. ROI coding passes=" + nROIcp + ", sb=" + sb.sbandIdx;
// str += "\n\ttruncRates:\n";
// for(int i=0; i<truncRates.length; i++) {
// str += "\t "+i+": "+truncRates[i]+"\n";
// }
return str;
}
}
}
Generated by GNU Enscript 1.6.5.90.