add implementation for kaldi io (by ymz)

1 files changed, 532 insertions, 0 deletions

diff --git a/kaldi_io/src/tools/openfst/include/fst/bi-table.h b/kaldi_io/src/tools/openfst/include/fst/bi-table.h
new file mode 100644
index 0000000..d220ce4
--- /dev/null
+++ b/kaldi_io/src/tools/openfst/include/fst/bi-table.h
@@ -0,0 +1,532 @@
+// bi-table.h
+
+// 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
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2005-2010 Google, Inc.
+// Author: [email protected] (Michael Riley)
+//
+// \file
+// Classes for representing a bijective mapping between an arbitrary entry
+// of type T and a signed integral ID.
+
+#ifndef FST_LIB_BI_TABLE_H__
+#define FST_LIB_BI_TABLE_H__
+
+#include <deque>
+using std::deque;
+#include <functional>
+#include <vector>
+using std::vector;
+
+#include <tr1/unordered_set>
+using std::tr1::unordered_set;
+using std::tr1::unordered_multiset;
+
+namespace fst {
+
+// BI TABLES - these determine a bijective mapping between an
+// arbitrary entry of type T and an signed integral ID of type I. The IDs are
+// allocated starting from 0 in order.
+//
+// template <class I, class T>
+// class BiTable {
+//  public:
+//
+//   // Required constructors.
+//   BiTable();
+//
+//   // Lookup integer ID from entry. If it doesn't exist and 'insert'
+//   / is true, then add it. Otherwise return -1.
+//   I FindId(const T &entry, bool insert = true);
+//   // Lookup entry from integer ID.
+//   const T &FindEntry(I) const;
+//   // # of stored entries.
+//   I Size() const;
+// };
+
+// An implementation using a hash map for the entry to ID mapping.
+// H is the hash function and E is the equality function.
+// If passed to the constructor, ownership is given to this class.
+
+template <class I, class T, class H, class E = std::equal_to<T> >
+class HashBiTable {
+ public:
+  // Reserves space for 'table_size' elements.
+  explicit HashBiTable(size_t table_size = 0, H *h = 0, E *e = 0)
+      : hash_func_(h),
+        hash_equal_(e),
+        entry2id_(table_size, (h ? *h : H()), (e ? *e : E())) {
+    if (table_size)
+      id2entry_.reserve(table_size);
+  }
+
+  HashBiTable(const HashBiTable<I, T, H, E> &table)
+      : hash_func_(table.hash_func_ ? new H(*table.hash_func_) : 0),
+        hash_equal_(table.hash_equal_ ? new E(*table.hash_equal_) : 0),
+        entry2id_(table.entry2id_.begin(), table.entry2id_.end(),
+                  table.entry2id_.size(),
+                  (hash_func_ ? *hash_func_ : H()),
+                  (hash_equal_ ? *hash_equal_ : E())),
+        id2entry_(table.id2entry_) { }
+
+  ~HashBiTable() {
+    delete hash_func_;
+    delete hash_equal_;
+  }
+
+  I FindId(const T &entry, bool insert = true) {
+    I &id_ref = entry2id_[entry];
+    if (id_ref == 0) {  // T not found
+      if (insert) {     // store and assign it a new ID
+        id2entry_.push_back(entry);
+        id_ref = id2entry_.size();
+      } else {
+        return -1;
+      }
+    }
+    return id_ref - 1;  // NB: id_ref = ID + 1
+  }
+
+  const T &FindEntry(I s) const {
+    return id2entry_[s];
+  }
+
+  I Size() const { return id2entry_.size(); }
+
+ private:
+  H *hash_func_;
+  E *hash_equal_;
+  unordered_map<T, I, H, E> entry2id_;
+  vector<T> id2entry_;
+
+  void operator=(const HashBiTable<I, T, H, E> &table);  // disallow
+};
+
+
+// Enables alternative hash set representations below.
+// typedef enum { HS_STL = 0, HS_DENSE = 1, HS_SPARSE = 2 } HSType;
+typedef enum { HS_STL = 0, HS_DENSE = 1, HS_SPARSE = 2 } HSType;
+
+// Default hash set is STL hash_set
+template<class K, class H, class E, HSType>
+struct  HashSet : public unordered_set<K, H, E> {
+  HashSet(size_t n = 0, const H &h = H(), const E &e = E())
+      : unordered_set<K, H, E>(n, h, e)  { }
+
+  void rehash(size_t n) { }
+};
+
+
+// An implementation using a hash set for the entry to ID mapping.
+// The hash set holds 'keys' which are either the ID or kCurrentKey.
+// These keys can be mapped to entrys either by looking up in the
+// entry vector or, if kCurrentKey, in current_entry_ member. The hash
+// and key equality functions map to entries first. H
+// is the hash function and E is the equality function. If passed to
+// the constructor, ownership is given to this class.
+template <class I, class T, class H,
+          class E = std::equal_to<T>, HSType HS = HS_DENSE>
+class CompactHashBiTable {
+ public:
+  friend class HashFunc;
+  friend class HashEqual;
+
+  // Reserves space for 'table_size' elements.
+  explicit CompactHashBiTable(size_t table_size = 0, H *h = 0, E *e = 0)
+      : hash_func_(h),
+        hash_equal_(e),
+        compact_hash_func_(*this),
+        compact_hash_equal_(*this),
+        keys_(table_size, compact_hash_func_, compact_hash_equal_) {
+    if (table_size)
+      id2entry_.reserve(table_size);
+  }
+
+  CompactHashBiTable(const CompactHashBiTable<I, T, H, E, HS> &table)
+      : hash_func_(table.hash_func_ ? new H(*table.hash_func_) : 0),
+        hash_equal_(table.hash_equal_ ? new E(*table.hash_equal_) : 0),
+        compact_hash_func_(*this),
+        compact_hash_equal_(*this),
+        keys_(table.keys_.size(), compact_hash_func_, compact_hash_equal_),
+        id2entry_(table.id2entry_) {
+    keys_.insert(table.keys_.begin(), table.keys_.end());
+ }
+
+  ~CompactHashBiTable() {
+    delete hash_func_;
+    delete hash_equal_;
+  }
+
+  I FindId(const T &entry, bool insert = true) {
+    current_entry_ = &entry;
+    typename KeyHashSet::const_iterator it = keys_.find(kCurrentKey);
+    if (it == keys_.end()) {  // T not found
+      if (insert) {           // store and assign it a new ID
+        I key = id2entry_.size();
+        id2entry_.push_back(entry);
+        keys_.insert(key);
+        return key;
+      } else {
+        return -1;
+      }
+    } else {
+      return *it;
+    }
+  }
+
+  const T &FindEntry(I s) const { return id2entry_[s]; }
+
+  I Size() const { return id2entry_.size(); }
+
+  // Clear content. With argument, erases last n IDs.
+  void Clear(ssize_t n = -1) {
+    if (n < 0 || n > id2entry_.size())
+      n = id2entry_.size();
+    while (n-- > 0) {
+      I key = id2entry_.size() - 1;
+      keys_.erase(key);
+      id2entry_.pop_back();
+    }
+    keys_.rehash(0);
+  }
+
+ private:
+  static const I kCurrentKey;    // -1
+  static const I kEmptyKey;      // -2
+  static const I kDeletedKey;    // -3
+
+  class HashFunc {
+   public:
+    HashFunc(const CompactHashBiTable &ht) : ht_(&ht) {}
+
+    size_t operator()(I k) const {
+      if (k >= kCurrentKey) {
+        return (*ht_->hash_func_)(ht_->Key2Entry(k));
+      } else {
+        return 0;
+      }
+    }
+
+   private:
+    const CompactHashBiTable *ht_;
+  };
+
+  class HashEqual {
+   public:
+    HashEqual(const CompactHashBiTable &ht) : ht_(&ht) {}
+
+    bool operator()(I k1, I k2) const {
+      if (k1 >= kCurrentKey && k2 >= kCurrentKey) {
+        return (*ht_->hash_equal_)(ht_->Key2Entry(k1), ht_->Key2Entry(k2));
+      } else {
+        return k1 == k2;
+      }
+    }
+   private:
+    const CompactHashBiTable *ht_;
+  };
+
+  typedef HashSet<I, HashFunc, HashEqual, HS> KeyHashSet;
+
+  const T &Key2Entry(I k) const {
+    if (k == kCurrentKey)
+      return *current_entry_;
+    else
+      return id2entry_[k];
+  }
+
+  H *hash_func_;
+  E *hash_equal_;
+  HashFunc compact_hash_func_;
+  HashEqual compact_hash_equal_;
+  KeyHashSet keys_;
+  vector<T> id2entry_;
+  const T *current_entry_;
+
+  void operator=(const CompactHashBiTable<I, T, H, E, HS> &table);  // disallow
+};
+
+
+template <class I, class T, class H, class E, HSType HS>
+const I CompactHashBiTable<I, T, H, E, HS>::kCurrentKey = -1;
+
+template <class I, class T, class H, class E, HSType HS>
+const I CompactHashBiTable<I, T, H, E, HS>::kEmptyKey = -2;
+
+template <class I, class T, class H, class E, HSType HS>
+const I CompactHashBiTable<I, T, H, E, HS>::kDeletedKey = -3;
+
+
+// An implementation using a vector for the entry to ID mapping.
+// It is passed a function object FP that should fingerprint entries
+// uniquely to an integer that can used as a vector index. Normally,
+// VectorBiTable constructs the FP object.  The user can instead
+// pass in this object; in that case, VectorBiTable takes its
+// ownership.
+template <class I, class T, class FP>
+class VectorBiTable {
+ public:
+  // Reserves space for 'table_size' elements.
+  explicit VectorBiTable(FP *fp = 0, size_t table_size = 0)
+      : fp_(fp ? fp : new FP()) {
+    if (table_size)
+      id2entry_.reserve(table_size);
+  }
+
+  VectorBiTable(const VectorBiTable<I, T, FP> &table)
+      : fp_(table.fp_ ? new FP(*table.fp_) : 0),
+        fp2id_(table.fp2id_),
+        id2entry_(table.id2entry_) { }
+
+  ~VectorBiTable() { delete fp_; }
+
+  I FindId(const T &entry, bool insert = true) {
+    ssize_t fp = (*fp_)(entry);
+    if (fp >= fp2id_.size())
+      fp2id_.resize(fp + 1);
+    I &id_ref = fp2id_[fp];
+    if (id_ref == 0) {  // T not found
+      if (insert) {     // store and assign it a new ID
+        id2entry_.push_back(entry);
+        id_ref = id2entry_.size();
+      } else {
+        return -1;
+      }
+    }
+    return id_ref - 1;  // NB: id_ref = ID + 1
+  }
+
+  const T &FindEntry(I s) const { return id2entry_[s]; }
+
+  I Size() const { return id2entry_.size(); }
+
+  const FP &Fingerprint() const { return *fp_; }
+
+ private:
+  FP *fp_;
+  vector<I> fp2id_;
+  vector<T> id2entry_;
+
+  void operator=(const VectorBiTable<I, T, FP> &table);  // disallow
+};
+
+
+// An implementation using a vector and a compact hash table. The
+// selecting functor S returns true for entries to be hashed in the
+// vector.  The fingerprinting functor FP returns a unique fingerprint
+// for each entry to be hashed in the vector (these need to be
+// suitable for indexing in a vector).  The hash functor H is used
+// when hashing entry into the compact hash table.  If passed to the
+// constructor, ownership is given to this class.
+template <class I, class T, class S, class FP, class H, HSType HS = HS_DENSE>
+class VectorHashBiTable {
+ public:
+  friend class HashFunc;
+  friend class HashEqual;
+
+  explicit VectorHashBiTable(S *s, FP *fp = 0, H *h = 0,
+                             size_t vector_size = 0,
+                             size_t entry_size = 0)
+      : selector_(s),
+        fp_(fp ? fp : new FP()),
+        h_(h ? h : new H()),
+        hash_func_(*this),
+        hash_equal_(*this),
+        keys_(0, hash_func_, hash_equal_) {
+    if (vector_size)
+      fp2id_.reserve(vector_size);
+    if (entry_size)
+      id2entry_.reserve(entry_size);
+ }
+
+  VectorHashBiTable(const VectorHashBiTable<I, T, S, FP, H, HS> &table)
+      : selector_(new S(table.s_)),
+        fp_(table.fp_ ? new FP(*table.fp_) : 0),
+        h_(table.h_ ? new H(*table.h_) : 0),
+        id2entry_(table.id2entry_),
+        fp2id_(table.fp2id_),
+        hash_func_(*this),
+        hash_equal_(*this),
+        keys_(table.keys_.size(), hash_func_, hash_equal_) {
+     keys_.insert(table.keys_.begin(), table.keys_.end());
+  }
+
+  ~VectorHashBiTable() {
+    delete selector_;
+    delete fp_;
+    delete h_;
+  }
+
+  I FindId(const T &entry, bool insert = true) {
+    if ((*selector_)(entry)) {  // Use the vector if 'selector_(entry) == true'
+      uint64 fp = (*fp_)(entry);
+      if (fp2id_.size() <= fp)
+        fp2id_.resize(fp + 1, 0);
+      if (fp2id_[fp] == 0) {         // T not found
+        if (insert) {                // store and assign it a new ID
+          id2entry_.push_back(entry);
+          fp2id_[fp] = id2entry_.size();
+        } else {
+          return -1;
+        }
+      }
+      return fp2id_[fp] - 1;  // NB: assoc_value = ID + 1
+    } else {  // Use the hash table otherwise.
+      current_entry_ = &entry;
+      typename KeyHashSet::const_iterator it = keys_.find(kCurrentKey);
+      if (it == keys_.end()) {
+        if (insert) {
+          I key = id2entry_.size();
+          id2entry_.push_back(entry);
+          keys_.insert(key);
+          return key;
+        } else {
+          return -1;
+        }
+      } else {
+        return *it;
+      }
+    }
+  }
+
+  const T &FindEntry(I s) const {
+    return id2entry_[s];
+  }
+
+  I Size() const { return id2entry_.size(); }
+
+  const S &Selector() const { return *selector_; }
+
+  const FP &Fingerprint() const { return *fp_; }
+
+  const H &Hash() const { return *h_; }
+
+ private:
+  static const I kCurrentKey;  // -1
+  static const I kEmptyKey;    // -2
+
+  class HashFunc {
+   public:
+    HashFunc(const VectorHashBiTable &ht) : ht_(&ht) {}
+
+    size_t operator()(I k) const {
+      if (k >= kCurrentKey) {
+        return (*(ht_->h_))(ht_->Key2Entry(k));
+      } else {
+        return 0;
+      }
+    }
+   private:
+    const VectorHashBiTable *ht_;
+  };
+
+  class HashEqual {
+   public:
+    HashEqual(const VectorHashBiTable &ht) : ht_(&ht) {}
+
+    bool operator()(I k1, I k2) const {
+      if (k1 >= kCurrentKey && k2 >= kCurrentKey) {
+        return ht_->Key2Entry(k1) == ht_->Key2Entry(k2);
+      } else {
+        return k1 == k2;
+      }
+    }
+   private:
+    const VectorHashBiTable *ht_;
+  };
+
+  typedef HashSet<I, HashFunc, HashEqual, HS> KeyHashSet;
+
+  const T &Key2Entry(I k) const {
+    if (k == kCurrentKey)
+      return *current_entry_;
+    else
+      return id2entry_[k];
+  }
+
+  S *selector_;  // Returns true if entry hashed into vector
+  FP *fp_;       // Fingerprint used when hashing entry into vector
+  H *h_;         // Hash function used when hashing entry into hash_set
+
+  vector<T> id2entry_;  // Maps state IDs to entry
+  vector<I> fp2id_;     // Maps entry fingerprints to IDs
+
+  // Compact implementation of the hash table mapping entrys to
+  // state IDs using the hash function 'h_'
+  HashFunc hash_func_;
+  HashEqual hash_equal_;
+  KeyHashSet keys_;
+  const T *current_entry_;
+
+  // disallow
+  void operator=(const VectorHashBiTable<I, T, S, FP, H, HS> &table);
+};
+
+template <class I, class T, class S, class FP, class H, HSType HS>
+const I VectorHashBiTable<I, T, S, FP, H, HS>::kCurrentKey = -1;
+
+template <class I, class T, class S, class FP, class H, HSType HS>
+const I VectorHashBiTable<I, T, S, FP, H, HS>::kEmptyKey = -3;
+
+
+// An implementation using a hash map for the entry to ID
+// mapping. This version permits erasing of arbitrary states.  The
+// entry T must have == defined and its default constructor must
+// produce a entry that will never be seen. F is the hash function.
+template <class I, class T, class F>
+class ErasableBiTable {
+ public:
+  ErasableBiTable() : first_(0) {}
+
+  I FindId(const T &entry, bool insert = true) {
+    I &id_ref = entry2id_[entry];
+    if (id_ref == 0) {  // T not found
+      if (insert) {     // store and assign it a new ID
+        id2entry_.push_back(entry);
+        id_ref = id2entry_.size() + first_;
+      } else {
+        return -1;
+      }
+    }
+    return id_ref - 1;  // NB: id_ref = ID + 1
+  }
+
+  const T &FindEntry(I s) const { return id2entry_[s - first_]; }
+
+  I Size() const { return id2entry_.size(); }
+
+  void Erase(I s) {
+    T &entry = id2entry_[s - first_];
+    typename unordered_map<T, I, F>::iterator it =
+        entry2id_.find(entry);
+    entry2id_.erase(it);
+    id2entry_[s - first_] = empty_entry_;
+    while (!id2entry_.empty() && id2entry_.front() == empty_entry_) {
+      id2entry_.pop_front();
+      ++first_;
+    }
+  }
+
+ private:
+  unordered_map<T, I, F> entry2id_;
+  deque<T> id2entry_;
+  const T empty_entry_;
+  I first_;        // I of first element in the deque;
+
+  // disallow
+  void operator=(const ErasableBiTable<I, T, F> &table);  //disallow
+};
+
+}  // namespace fst
+
+#endif  // FST_LIB_BI_TABLE_H__