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diff --git a/kaldi_io/src/kaldi/hmm/transition-model.h b/kaldi_io/src/kaldi/hmm/transition-model.h deleted file mode 100644 index ccc4f11..0000000 --- a/kaldi_io/src/kaldi/hmm/transition-model.h +++ /dev/null @@ -1,345 +0,0 @@ -// hmm/transition-model.h - -// Copyright 2009-2012 Microsoft Corporation -// Johns Hopkins University (author: Guoguo Chen) - -// See ../../COPYING for clarification regarding multiple authors -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY -// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED -// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE, -// MERCHANTABLITY OR NON-INFRINGEMENT. -// See the Apache 2 License for the specific language governing permissions and -// limitations under the License. - -#ifndef KALDI_HMM_TRANSITION_MODEL_H_ -#define KALDI_HMM_TRANSITION_MODEL_H_ - -#include "base/kaldi-common.h" -#include "tree/context-dep.h" -#include "util/const-integer-set.h" -#include "fst/fst-decl.h" // forward declarations. -#include "hmm/hmm-topology.h" -#include "itf/options-itf.h" - -namespace kaldi { - -/// \addtogroup hmm_group -/// @{ - -// The class TransitionModel is a repository for the transition probabilities. -// It also handles certain integer mappings. -// The basic model is as follows. Each phone has a HMM topology defined in -// hmm-topology.h. Each HMM-state of each of these phones has a number of -// transitions (and final-probs) out of it. Each HMM-state defined in the -// HmmTopology class has an associated "pdf_class". This gets replaced with -// an actual pdf-id via the tree. The transition model associates the -// transition probs with the (phone, HMM-state, pdf-id). We associate with -// each such triple a transition-state. Each -// transition-state has a number of associated probabilities to estimate; -// this depends on the number of transitions/final-probs in the topology for -// that (phone, HMM-state). Each probability has an associated transition-index. -// We associate with each (transition-state, transition-index) a unique transition-id. -// Each individual probability estimated by the transition-model is asociated with a -// transition-id. -// -// List of the various types of quantity referred to here and what they mean: -// phone: a phone index (1, 2, 3 ...) -// HMM-state: a number (0, 1, 2...) that indexes TopologyEntry (see hmm-topology.h) -// pdf-id: a number output by the Compute function of ContextDependency (it -// indexes pdf's). Zero-based. -// transition-state: the states for which we estimate transition probabilities for transitions -// out of them. In some topologies, will map one-to-one with pdf-ids. -// One-based, since it appears on FSTs. -// transition-index: identifier of a transition (or final-prob) in the HMM. Indexes the -// "transitions" vector in HmmTopology::HmmState. [if it is out of range, -// equal to transitions.size(), it refers to the final-prob.] -// Zero-based. -// transition-id: identifier of a unique parameter of the TransitionModel. -// Associated with a (transition-state, transition-index) pair. -// One-based, since it appears on FSTs. -// -// List of the possible mappings TransitionModel can do: -// (phone, HMM-state, pdf-id) -> transition-state -// (transition-state, transition-index) -> transition-id -// Reverse mappings: -// transition-id -> transition-state -// transition-id -> transition-index -// transition-state -> phone -// transition-state -> HMM-state -// transition-state -> pdf-id -// -// The main things the TransitionModel object can do are: -// Get initialized (need ContextDependency and HmmTopology objects). -// Read/write. -// Update [given a vector of counts indexed by transition-id]. -// Do the various integer mappings mentioned above. -// Get the probability (or log-probability) associated with a particular transition-id. - - -// Note: this was previously called TransitionUpdateConfig. -struct MleTransitionUpdateConfig { - BaseFloat floor; - BaseFloat mincount; - bool share_for_pdfs; // If true, share all transition parameters that have the same pdf. - MleTransitionUpdateConfig(BaseFloat floor = 0.01, - BaseFloat mincount = 5.0, - bool share_for_pdfs = false): - floor(floor), mincount(mincount), share_for_pdfs(share_for_pdfs) {} - - void Register (OptionsItf *po) { - po->Register("transition-floor", &floor, - "Floor for transition probabilities"); - po->Register("transition-min-count", &mincount, - "Minimum count required to update transitions from a state"); - po->Register("share-for-pdfs", &share_for_pdfs, - "If true, share all transition parameters where the states " - "have the same pdf."); - } -}; - -struct MapTransitionUpdateConfig { - BaseFloat tau; - bool share_for_pdfs; // If true, share all transition parameters that have the same pdf. - MapTransitionUpdateConfig(): tau(5.0), share_for_pdfs(false) { } - - void Register (OptionsItf *po) { - po->Register("transition-tau", &tau, "Tau value for MAP estimation of transition " - "probabilities."); - po->Register("share-for-pdfs", &share_for_pdfs, - "If true, share all transition parameters where the states " - "have the same pdf."); - } -}; - -class TransitionModel { - - public: - /// Initialize the object [e.g. at the start of training]. - /// The class keeps a copy of the HmmTopology object, but not - /// the ContextDependency object. - TransitionModel(const ContextDependency &ctx_dep, - const HmmTopology &hmm_topo); - - - /// Constructor that takes no arguments: typically used prior to calling Read. - TransitionModel() { } - - void Read(std::istream &is, bool binary); // note, no symbol table: topo object always read/written w/o symbols. - void Write(std::ostream &os, bool binary) const; - - - /// return reference to HMM-topology object. - const HmmTopology &GetTopo() const { return topo_; } - - /// \name Integer mapping functions - /// @{ - - int32 TripleToTransitionState(int32 phone, int32 hmm_state, int32 pdf) const; - int32 PairToTransitionId(int32 trans_state, int32 trans_index) const; - int32 TransitionIdToTransitionState(int32 trans_id) const; - int32 TransitionIdToTransitionIndex(int32 trans_id) const; - int32 TransitionStateToPhone(int32 trans_state) const; - int32 TransitionStateToHmmState(int32 trans_state) const; - int32 TransitionStateToPdf(int32 trans_state) const; - int32 SelfLoopOf(int32 trans_state) const; // returns the self-loop transition-id, or zero if - // this state doesn't have a self-loop. - - inline int32 TransitionIdToPdf(int32 trans_id) const; - int32 TransitionIdToPhone(int32 trans_id) const; - int32 TransitionIdToPdfClass(int32 trans_id) const; - int32 TransitionIdToHmmState(int32 trans_id) const; - - /// @} - - bool IsFinal(int32 trans_id) const; // returns true if this trans_id goes to the final state - // (which is bound to be nonemitting). - bool IsSelfLoop(int32 trans_id) const; // return true if this trans_id corresponds to a self-loop. - - /// Returns the total number of transition-ids (note, these are one-based). - inline int32 NumTransitionIds() const { return id2state_.size()-1; } - - /// Returns the number of transition-indices for a particular transition-state. - /// Note: "Indices" is the plural of "index". Index is not the same as "id", - /// here. A transition-index is a zero-based offset into the transitions - /// out of a particular transition state. - int32 NumTransitionIndices(int32 trans_state) const; - - /// Returns the total number of transition-states (note, these are one-based). - int32 NumTransitionStates() const { return triples_.size(); } - - // NumPdfs() actually returns the highest-numbered pdf we ever saw, plus one. - // In normal cases this should equal the number of pdfs in the system, but if you - // initialized this object with fewer than all the phones, and it happens that - // an unseen phone has the highest-numbered pdf, this might be different. - int32 NumPdfs() const { return num_pdfs_; } - - // This loops over the triples and finds the highest phone index present. If - // the FST symbol table for the phones is created in the expected way, i.e.: - // starting from 1 (<eps> is 0) and numbered contiguously till the last phone, - // this will be the total number of phones. - int32 NumPhones() const; - - /// Returns a sorted, unique list of phones. - const std::vector<int32> &GetPhones() const { return topo_.GetPhones(); } - - // Transition-parameter-getting functions: - BaseFloat GetTransitionProb(int32 trans_id) const; - BaseFloat GetTransitionLogProb(int32 trans_id) const; - - // The following functions are more specialized functions for getting - // transition probabilities, that are provided for convenience. - - /// Returns the log-probability of a particular non-self-loop transition - /// after subtracting the probability mass of the self-loop and renormalizing; - /// will crash if called on a self-loop. Specifically: - /// for non-self-loops it returns the log of that prob divided by (1 minus - /// self-loop-prob-for-that-state). - BaseFloat GetTransitionLogProbIgnoringSelfLoops(int32 trans_id) const; - - /// Returns the log-prob of the non-self-loop probability - /// mass for this transition state. (you can get the self-loop prob, if a self-loop - /// exists, by calling GetTransitionLogProb(SelfLoopOf(trans_state)). - BaseFloat GetNonSelfLoopLogProb(int32 trans_state) const; - - /// Does Maximum Likelihood estimation. The stats are counts/weights, indexed - /// by transition-id. This was previously called Update(). - void MleUpdate(const Vector<double> &stats, - const MleTransitionUpdateConfig &cfg, - BaseFloat *objf_impr_out, - BaseFloat *count_out); - - /// Does Maximum A Posteriori (MAP) estimation. The stats are counts/weights, - /// indexed by transition-id. - void MapUpdate(const Vector<double> &stats, - const MapTransitionUpdateConfig &cfg, - BaseFloat *objf_impr_out, - BaseFloat *count_out); - - /// Print will print the transition model in a human-readable way, for purposes of human - /// inspection. The "occs" are optional (they are indexed by pdf-id). - void Print(std::ostream &os, - const std::vector<std::string> &phone_names, - const Vector<double> *occs = NULL); - - - void InitStats(Vector<double> *stats) const { stats->Resize(NumTransitionIds()+1); } - - void Accumulate(BaseFloat prob, int32 trans_id, Vector<double> *stats) const { - KALDI_ASSERT(trans_id <= NumTransitionIds()); - (*stats)(trans_id) += prob; - // This is trivial and doesn't require class members, but leaves us more open - // to design changes than doing it manually. - } - - /// returns true if all the integer class members are identical (but does not - /// compare the transition probabilities. - bool Compatible(const TransitionModel &other) const; - - private: - void MleUpdateShared(const Vector<double> &stats, - const MleTransitionUpdateConfig &cfg, - BaseFloat *objf_impr_out, BaseFloat *count_out); - void MapUpdateShared(const Vector<double> &stats, - const MapTransitionUpdateConfig &cfg, - BaseFloat *objf_impr_out, BaseFloat *count_out); - void ComputeTriples(const ContextDependency &ctx_dep); // called from constructor. initializes triples_. - void ComputeDerived(); // called from constructor and Read function: computes state2id_ and id2state_. - void ComputeDerivedOfProbs(); // computes quantities derived from log-probs (currently just - // non_self_loop_log_probs_; called whenever log-probs change. - void InitializeProbs(); // called from constructor. - void Check() const; - - struct Triple { - int32 phone; - int32 hmm_state; - int32 pdf; - Triple() { } - Triple(int32 phone, int32 hmm_state, int32 pdf): - phone(phone), hmm_state(hmm_state), pdf(pdf) { } - bool operator < (const Triple &other) const { - if (phone < other.phone) return true; - else if (phone > other.phone) return false; - else if (hmm_state < other.hmm_state) return true; - else if (hmm_state > other.hmm_state) return false; - else return pdf < other.pdf; - } - bool operator == (const Triple &other) const { - return (phone == other.phone && hmm_state == other.hmm_state - && pdf == other.pdf); - } - }; - - HmmTopology topo_; - - /// Triples indexed by transition state minus one; - /// the triples are in sorted order which allows us to do the reverse mapping from - /// triple to transition state - std::vector<Triple> triples_; - - /// Gives the first transition_id of each transition-state; indexed by - /// the transition-state. Array indexed 1..num-transition-states+1 (the last one - /// is needed so we can know the num-transitions of the last transition-state. - std::vector<int32> state2id_; - - /// For each transition-id, the corresponding transition - /// state (indexed by transition-id). - std::vector<int32> id2state_; - - /// For each transition-id, the corresponding log-prob. Indexed by transition-id. - Vector<BaseFloat> log_probs_; - - /// For each transition-state, the log of (1 - self-loop-prob). Indexed by - /// transition-state. - Vector<BaseFloat> non_self_loop_log_probs_; - - /// This is actually one plus the highest-numbered pdf we ever got back from the - /// tree (but the tree numbers pdfs contiguously from zero so this is the number - /// of pdfs). - int32 num_pdfs_; - - - DISALLOW_COPY_AND_ASSIGN(TransitionModel); - -}; - -inline int32 TransitionModel::TransitionIdToPdf(int32 trans_id) const { - // If a lot of time is spent here we may create an extra array - // to handle this. - KALDI_ASSERT(static_cast<size_t>(trans_id) < id2state_.size() && - "Likely graph/model mismatch (graph built from wrong model?)"); - int32 trans_state = id2state_[trans_id]; - return triples_[trans_state-1].pdf; -} - -/// Works out which pdfs might correspond to the given phones. Will return true -/// if these pdfs correspond *just* to these phones, false if these pdfs are also -/// used by other phones. -/// @param trans_model [in] Transition-model used to work out this information -/// @param phones [in] A sorted, uniq vector that represents a set of phones -/// @param pdfs [out] Will be set to a sorted, uniq list of pdf-ids that correspond -/// to one of this set of phones. -/// @return Returns true if all of the pdfs output to "pdfs" correspond to phones from -/// just this set (false if they may be shared with phones outside this set). -bool GetPdfsForPhones(const TransitionModel &trans_model, - const std::vector<int32> &phones, - std::vector<int32> *pdfs); - -/// Works out which phones might correspond to the given pdfs. Similar to the -/// above GetPdfsForPhones(, ,) -bool GetPhonesForPdfs(const TransitionModel &trans_model, - const std::vector<int32> &pdfs, - std::vector<int32> *phones); -/// @} - - -} // end namespace kaldi - - -#endif |