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Diffstat (limited to 'kaldi_io/src/kaldi/hmm/hmm-topology.h')
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diff --git a/kaldi_io/src/kaldi/hmm/hmm-topology.h b/kaldi_io/src/kaldi/hmm/hmm-topology.h deleted file mode 100644 index 53ca427..0000000 --- a/kaldi_io/src/kaldi/hmm/hmm-topology.h +++ /dev/null @@ -1,172 +0,0 @@ -// hmm/hmm-topology.h - -// Copyright 2009-2011 Microsoft Corporation - -// 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_HMM_TOPOLOGY_H_ -#define KALDI_HMM_HMM_TOPOLOGY_H_ - -#include "base/kaldi-common.h" -#include "tree/context-dep.h" -#include "util/const-integer-set.h" - - -namespace kaldi { - - -/// \addtogroup hmm_group -/// @{ - -/* - // The following would be the text form for the "normal" HMM topology. - // Note that the first state is the start state, and the final state, - // which must have no output transitions and must be nonemitting, has - // an exit probability of one (no other state can have nonzero exit - // probability; you can treat the transition probability to the final - // state as an exit probability). - // Note also that it's valid to omit the "<PdfClass>" entry of the <State>, which - // will mean we won't have a pdf on that state [non-emitting state]. This is equivalent - // to setting the <PdfClass> to -1. We do this normally just for the final state. - // The Topology object can have multiple <TopologyEntry> blocks. - // This is useful if there are multiple types of topology in the system. - - <Topology> - <TopologyEntry> - <ForPhones> 1 2 3 4 5 6 7 8 </ForPhones> - <State> 0 <PdfClass> 0 - <Transition> 0 0.5 - <Transition> 1 0.5 - </State> - <State> 1 <PdfClass> 1 - <Transition> 1 0.5 - <Transition> 2 0.5 - </State> - <State> 2 <PdfClass> 2 - <Transition> 2 0.5 - <Transition> 3 0.5 - <Final> 0.5 - </State> - <State> 3 - </State> - </TopologyEntry> - </Topology> -*/ - -// kNoPdf is used where pdf_class or pdf would be used, to indicate, -// none is there. Mainly useful in skippable models, but also used -// for end states. -// A caveat with nonemitting states is that their out-transitions -// are not trainable, due to technical issues with the way -// we decided to accumulate the stats. Any transitions arising from (*) -// HMM states with "kNoPdf" as the label are second-class transitions, -// They do not have "transition-states" or "transition-ids" associated -// with them. They are used to create the FST version of the -// HMMs, where they lead to epsilon arcs. -// (*) "arising from" is a bit of a technical term here, due to the way -// (if reorder == true), we put the transition-id associated with the -// outward arcs of the state, on the input transition to the state. - -/// A constant used in the HmmTopology class as the \ref pdf_class "pdf-class" -/// kNoPdf, which is used when a HMM-state is nonemitting (has no associated -/// PDF). - -static const int32 kNoPdf = -1; - -/// A class for storing topology information for phones. See \ref hmm for context. -/// This object is sometimes accessed in a file by itself, but more often -/// as a class member of the Transition class (this is for convenience to reduce -/// the number of files programs have to access). - -class HmmTopology { - public: - /// A structure defined inside HmmTopology to represent a HMM state. - struct HmmState { - /// The \ref pdf_class pdf-class, typically 0, 1 or 2 (the same as the HMM-state index), - /// but may be different to enable us to hardwire sharing of state, and may be - /// equal to \ref kNoPdf == -1 in order to specify nonemitting states (unusual). - int32 pdf_class; - - /// A list of transitions. The first member of each pair is the index of - /// the next HmmState, and the second is the default transition probability - /// (before training). - std::vector<std::pair<int32, BaseFloat> > transitions; - - explicit HmmState(int32 p): pdf_class(p) { } - - bool operator == (const HmmState &other) const { - return (pdf_class == other.pdf_class && transitions == other.transitions); - } - - HmmState(): pdf_class(-1) { } - }; - - /// TopologyEntry is a typedef that represents the topology of - /// a single (prototype) state. - typedef std::vector<HmmState> TopologyEntry; - - void Read(std::istream &is, bool binary); - void Write(std::ostream &os, bool binary) const; - - // Checks that the object is valid, and throw exception otherwise. - void Check(); - - - /// Returns the topology entry (i.e. vector of HmmState) for this phone; - /// will throw exception if phone not covered by the topology. - const TopologyEntry &TopologyForPhone(int32 phone) const; - - /// Returns the number of \ref pdf_class "pdf-classes" for this phone; - /// throws exception if phone not covered by this topology. - int32 NumPdfClasses(int32 phone) const; - - /// Returns a reference to a sorted, unique list of phones covered by - /// the topology (these phones will be positive integers, and usually - /// contiguous and starting from one but the toolkit doesn't assume - /// they are contiguous). - const std::vector<int32> &GetPhones() const { return phones_; }; - - /// Outputs a vector of int32, indexed by phone, that gives the - /// number of \ref pdf_class pdf-classes for the phones; this is - /// used by tree-building code such as BuildTree(). - void GetPhoneToNumPdfClasses(std::vector<int32> *phone2num_pdf_classes) const; - - HmmTopology() {} - - bool operator == (const HmmTopology &other) const { - return phones_ == other.phones_ && phone2idx_ == other.phone2idx_ - && entries_ == other.entries_; - } - // Allow default assignment operator and copy constructor. - private: - std::vector<int32> phones_; // list of all phones we have topology for. Sorted, uniq. no epsilon (zero) phone. - std::vector<int32> phone2idx_; // map from phones to indexes into the entries vector (or -1 for not present). - std::vector<TopologyEntry> entries_; -}; - - -/// This function returns a HmmTopology object giving a normal 3-state topology, -/// covering all phones in the list "phones". This is mainly of use in testing -/// code. -HmmTopology GetDefaultTopology(const std::vector<int32> &phones); - -/// @} end "addtogroup hmm_group" - - -} // end namespace kaldi - - -#endif |