/**
* /// Attaches the given unit to the given tail, expanding the unit if necessary. If an identical unit is already
* /// attached, then this path is folded into the existing path.
*
* /// @param parent the parent state
* /// @param tail the place to attach the unit to
* /// @param units the set of units
* /// @param which the index into the set of units
* /// @param leftContext the left context for the unit
* /// @param rightContext the right context for the unit
* /// @return the tail of the added unit (or null if the path was folded onto an already expanded path.
*/
private SentenceHMMState AttachUnit(PronunciationState parent,
SentenceHMMState tail, Unit[] units, int which,
UnitContext leftContext, UnitContext rightContext)
{
Unit[] lc = GetLC(leftContext, units, which);
Unit[] rc = GetRC(units, which, rightContext);
UnitContext actualRightContext = UnitContext.Get(rc);
LeftRightContext context = LeftRightContext.Get(lc, rc);
Unit cdUnit = _parent.UnitManager.GetUnit(units[which].Name, units[which].IsFiller, context);
UnitState unitState = new ExtendedUnitState(parent, which, cdUnit);
float logInsertionProbability;
if (unitState.Unit.IsSilence)
{
logInsertionProbability = _parent.LogSilenceInsertionProbability;
}
else if (unitState.Unit.IsFiller)
{
logInsertionProbability = _parent._logFillerInsertionProbability;
}
else if (unitState.GetWhich() == 0)
{
logInsertionProbability = _parent._logWordInsertionProbability;
}
else
{
logInsertionProbability = _parent._logUnitInsertionProbability;
}
// check to see if this state already exists, if so
// branch to it and we are done, otherwise, branch to
// the new state and expand it.
SentenceHMMState existingState = GetExistingState(unitState);
if (existingState != null)
{
AttachState(tail, existingState, LogOne, logInsertionProbability);
// T(" Folding " + existingState);
return(null);
}
else
{
AttachState(tail, unitState, LogOne, logInsertionProbability);
AddStateToCache(unitState);
// T(" Attaching " + unitState);
tail = ExpandUnit(unitState);
// if we are attaching the last state of a word, then
// we add it to the exitPoints table. the exit points
// table is indexed by a ContextPair, consisting of
// the exiting left context and the right context.
if (unitState.IsLast())
{
UnitContext nextLeftContext = GenerateNextLeftContext(leftContext, units[which]);
ContextPair cp = ContextPair.Get(nextLeftContext, actualRightContext);
// T(" Adding to exitPoints " + cp);
AddExitPoint(cp, tail);
}
return(tail);
}
}
/**
* /// Given a unit, search for the HMM associated with this unit by replacing all non-silence filler contexts with the
* /// silence filler context
*
* /// @param unit the unit of interest
* /// @return the associated hmm or null
*/
private SenoneHMM GetHMMInSilenceContext(Unit unit, HMMPosition position)
{
SenoneHMM hmm = null;
var mgr = Loader.HMMManager;
var context = unit.Context;
if (context is LeftRightContext)
{
var lrContext = (LeftRightContext)context;
var lc = lrContext.LeftContext;
var rc = lrContext.RightContext;
Unit[] nlc;
Unit[] nrc;
if (HasNonSilenceFiller(lc))
{
nlc = ReplaceNonSilenceFillerWithSilence(lc);
}
else
{
nlc = lc;
}
if (HasNonSilenceFiller(rc))
{
nrc = ReplaceNonSilenceFillerWithSilence(rc);
}
else
{
nrc = rc;
}
if (nlc != lc || nrc != rc)
{
Context newContext = LeftRightContext.Get(nlc, nrc);
var newUnit = UnitManager.GetUnit(unit.Name,
unit.IsFiller, newContext);
hmm = (SenoneHMM)mgr.Get(position, newUnit);
if (hmm == null)
{
hmm = GetHMMAtAnyPosition(newUnit);
}
}
}
return(hmm);
}
/**
* /// Loads the sphinx3 density file, a set of density arrays are created and
* /// placed in the given pool.
* ///
* /// @param useCDUnits
* /// if true, loads also the context dependent units
* /// @param inputStream
* /// the open input stream to use
* /// @param path
* /// the path to a density file
* /// @throws FileNotFoundException
* /// if a file cannot be found
* /// @throws IOException
* /// if an error occurs while loading the data
*/
protected void LoadHMMPool(Boolean useCDUnits, Stream inputStream,
string path)
{
var est = new ExtendedStreamTokenizer(inputStream,
'#', false);
this.LogInfo("Loading HMM file from: " + path);
est.ExpectString(ModelVersion);
var numBase = est.GetInt("numBase");
est.ExpectString("n_base");
var numTri = est.GetInt("numTri");
est.ExpectString("n_tri");
var numStateMap = est.GetInt("numStateMap");
est.ExpectString("n_state_map");
var numTiedState = est.GetInt("numTiedState");
est.ExpectString("n_tied_state");
var numContextIndependentTiedState = est
.GetInt("numContextIndependentTiedState");
est.ExpectString("n_tied_ci_state");
var numTiedTransitionMatrices = est.GetInt("numTiedTransitionMatrices");
est.ExpectString("n_tied_tmat");
var numStatePerHMM = numStateMap / (numTri + numBase);
Debug.Assert(numTiedState == MixtureWeightsPool.StatesNum);
Debug.Assert(numTiedTransitionMatrices == MatrixPool.Size);
// Load the base phones
for (var i = 0; i < numBase; i++)
{
var name = est.GetString();
var left = est.GetString();
var right = est.GetString();
var position = est.GetString();
var attribute = est.GetString();
var tmat = est.GetInt("tmat");
var stid = new int[numStatePerHMM - 1];
for (var j = 0; j < numStatePerHMM - 1; j++)
{
stid[j] = est.GetInt("j");
Debug.Assert(stid[j] >= 0 && stid[j] < numContextIndependentTiedState);
}
est.ExpectString("N");
Debug.Assert(left.Equals("-"));
Debug.Assert(right.Equals("-"));
Debug.Assert(position.Equals("-"));
Debug.Assert(tmat < numTiedTransitionMatrices);
var unit = _unitManager.GetUnit(name, attribute.Equals(Filler));
ContextIndependentUnits.Put(unit.Name, unit);
//this.LogInfo("Loaded " + unit.ToString());
// The first filler
if (unit.IsFiller && unit.Name.Equals(SilenceCiphone))
{
unit = UnitManager.Silence;
}
var transitionMatrix = MatrixPool.Get(tmat);
var ss = GetSenoneSequence(stid);
IHMM hmm = new SenoneHMM(unit, ss, transitionMatrix, GetHMMPosition(position));
HmmManager.Put(hmm);
}
if (HmmManager.Get(HMMPosition.Undefined, UnitManager.Silence) == null)
{
throw new IOException("Could not find SIL unit in acoustic model");
}
// Load the context dependent phones. If the useCDUnits
// property is false, the CD phones will not be created, but
// the values still need to be read in from the file.
var lastUnitName = "";
Unit lastUnit = null;
int[] lastStid = null;
SenoneSequence lastSenoneSequence = null;
for (var i = 0; i < numTri; i++)
{
var name = est.GetString();
var left = est.GetString();
var right = est.GetString();
var position = est.GetString();
var attribute = est.GetString();
var tmat = est.GetInt("tmat");
var stid = new int[numStatePerHMM - 1];
for (var j = 0; j < numStatePerHMM - 1; j++)
{
stid[j] = est.GetInt("j");
Debug.Assert(stid[j] >= numContextIndependentTiedState &&
stid[j] < numTiedState);
}
est.ExpectString("N");
Debug.Assert(!left.Equals("-"));
Debug.Assert(!right.Equals("-"));
Debug.Assert(!position.Equals("-"));
Debug.Assert(attribute.Equals("n/a"));
Debug.Assert(tmat < numTiedTransitionMatrices);
if (useCDUnits)
{
Unit unit;
var unitName = (name + ' ' + left + ' ' + right);
if (unitName.Equals(lastUnitName))
{
unit = lastUnit;
}
else
{
var leftContext = new Unit[1];
leftContext[0] = ContextIndependentUnits.Get(left);
var rightContext = new Unit[1];
rightContext[0] = ContextIndependentUnits.Get(right);
Context context = LeftRightContext.Get(leftContext,
rightContext);
unit = _unitManager.GetUnit(name, false, context);
}
lastUnitName = unitName;
lastUnit = unit;
//this.LogInfo("Loaded " + unit.ToString());
var transitionMatrix = MatrixPool.Get(tmat);
var ss = lastSenoneSequence;
if (ss == null || !SameSenoneSequence(stid, lastStid))
{
ss = GetSenoneSequence(stid);
}
lastSenoneSequence = ss;
lastStid = stid;
IHMM hmm = new SenoneHMM(unit, ss, transitionMatrix, GetHMMPosition(position));
HmmManager.Put(hmm);
}
}
est.Close();
}