diff --git a/native/jni/Android.mk b/native/jni/Android.mk
index 1b758c680..0631b2255 100644
--- a/native/jni/Android.mk
+++ b/native/jni/Android.mk
@@ -58,6 +58,8 @@ LATIN_IME_CORE_SRC_FILES := \
         dic_nodes_cache.cpp) \
     $(addprefix suggest/core/dictionary/, \
         char_utils.cpp \
+        binary_dictionary_format.cpp \
+        byte_array_utils.cpp \
         dictionary.cpp \
         digraph_utils.cpp) \
     $(addprefix suggest/core/layout/, \
diff --git a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
index 9f5e2ae73..e80abf6e6 100644
--- a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
+++ b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
@@ -35,7 +35,8 @@
 #include "jni.h"
 #include "jni_common.h"
 #include "suggest_options.h"
-#include "suggest/core/dictionary/binary_format.h"
+#include "suggest/core/dictionary/binary_dictionary_format.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/dictionary.h"
 
 namespace latinime {
@@ -110,8 +111,8 @@ static jlong latinime_BinaryDictionary_open(JNIEnv *env, jclass clazz, jstring s
         return 0;
     }
     Dictionary *dictionary = 0;
-    if (BinaryFormat::UNKNOWN_FORMAT
-            == BinaryFormat::detectFormat(static_cast<uint8_t *>(dictBuf),
+    if (BinaryDictionaryFormat::UNKNOWN_VERSION
+            == BinaryDictionaryFormat::detectFormatVersion(static_cast<uint8_t *>(dictBuf),
                     static_cast<int>(dictSize))) {
         AKLOGE("DICT: dictionary format is unknown, bad magic number");
 #ifdef USE_MMAP_FOR_DICTIONARY
@@ -260,7 +261,7 @@ static jint latinime_BinaryDictionary_editDistance(JNIEnv *env, jclass clazz, ji
 static void latinime_BinaryDictionary_close(JNIEnv *env, jclass clazz, jlong dict) {
     Dictionary *dictionary = reinterpret_cast<Dictionary *>(dict);
     if (!dictionary) return;
-    const void *dictBuf = dictionary->getDict();
+    const void *dictBuf = dictionary->getBinaryDictionaryInfo()->getDictBuf();
     if (!dictBuf) return;
 #ifdef USE_MMAP_FOR_DICTIONARY
     releaseDictBuf(static_cast<const char *>(dictBuf) - dictionary->getDictBufAdjust(),
diff --git a/native/jni/src/bigram_dictionary.cpp b/native/jni/src/bigram_dictionary.cpp
index e04d8cfc1..b57227880 100644
--- a/native/jni/src/bigram_dictionary.cpp
+++ b/native/jni/src/bigram_dictionary.cpp
@@ -21,6 +21,7 @@
 #include "bigram_dictionary.h"
 
 #include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 #include "suggest/core/dictionary/bloom_filter.h"
 #include "suggest/core/dictionary/char_utils.h"
@@ -29,7 +30,8 @@
 
 namespace latinime {
 
-BigramDictionary::BigramDictionary(const uint8_t *const streamStart) : DICT_ROOT(streamStart) {
+BigramDictionary::BigramDictionary(const BinaryDictionaryInfo *const binaryDictionaryInfo)
+        : mBinaryDictionaryInfo(binaryDictionaryInfo) {
     if (DEBUG_DICT) {
         AKLOGI("BigramDictionary - constructor");
     }
@@ -104,7 +106,7 @@ int BigramDictionary::getBigrams(const int *prevWord, int prevWordLength, int *i
     // TODO: remove unused arguments, and refrain from storing stuff in members of this class
     // TODO: have "in" arguments before "out" ones, and make out args explicit in the name
 
-    const uint8_t *const root = DICT_ROOT;
+    const uint8_t *const root = mBinaryDictionaryInfo->getDictRoot();
     int pos = getBigramListPositionForWord(prevWord, prevWordLength,
             false /* forceLowerCaseSearch */);
     // getBigramListPositionForWord returns 0 if this word isn't in the dictionary or has no bigrams
@@ -150,7 +152,7 @@ int BigramDictionary::getBigrams(const int *prevWord, int prevWordLength, int *i
 int BigramDictionary::getBigramListPositionForWord(const int *prevWord, const int prevWordLength,
         const bool forceLowerCaseSearch) const {
     if (0 >= prevWordLength) return 0;
-    const uint8_t *const root = DICT_ROOT;
+    const uint8_t *const root = mBinaryDictionaryInfo->getDictRoot();
     int pos = BinaryFormat::getTerminalPosition(root, prevWord, prevWordLength,
             forceLowerCaseSearch);
 
@@ -171,7 +173,7 @@ int BigramDictionary::getBigramListPositionForWord(const int *prevWord, const in
 void BigramDictionary::fillBigramAddressToProbabilityMapAndFilter(const int *prevWord,
         const int prevWordLength, std::map<int, int> *map, uint8_t *filter) const {
     memset(filter, 0, BIGRAM_FILTER_BYTE_SIZE);
-    const uint8_t *const root = DICT_ROOT;
+    const uint8_t *const root = mBinaryDictionaryInfo->getDictRoot();
     int pos = getBigramListPositionForWord(prevWord, prevWordLength,
             false /* forceLowerCaseSearch */);
     if (0 == pos) {
@@ -210,7 +212,7 @@ bool BigramDictionary::checkFirstCharacter(int *word, int *inputCodePoints) cons
 
 bool BigramDictionary::isValidBigram(const int *word1, int length1, const int *word2,
         int length2) const {
-    const uint8_t *const root = DICT_ROOT;
+    const uint8_t *const root = mBinaryDictionaryInfo->getDictRoot();
     int pos = getBigramListPositionForWord(word1, length1, false /* forceLowerCaseSearch */);
     // getBigramListPositionForWord returns 0 if this word isn't in the dictionary or has no bigrams
     if (0 == pos) return false;
diff --git a/native/jni/src/bigram_dictionary.h b/native/jni/src/bigram_dictionary.h
index b86e564c3..8b7a253a2 100644
--- a/native/jni/src/bigram_dictionary.h
+++ b/native/jni/src/bigram_dictionary.h
@@ -24,9 +24,12 @@
 
 namespace latinime {
 
+class BinaryDictionaryInfo;
+
 class BigramDictionary {
  public:
-    BigramDictionary(const uint8_t *const streamStart);
+    BigramDictionary(const BinaryDictionaryInfo *const binaryDictionaryInfo);
+
     int getBigrams(const int *word, int length, int *inputCodePoints, int inputSize, int *outWords,
             int *frequencies, int *outputTypes) const;
     void fillBigramAddressToProbabilityMapAndFilter(const int *prevWord, const int prevWordLength,
@@ -35,13 +38,14 @@ class BigramDictionary {
     ~BigramDictionary();
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(BigramDictionary);
+
     void addWordBigram(int *word, int length, int probability, int *bigramProbability,
             int *bigramCodePoints, int *outputTypes) const;
     bool checkFirstCharacter(int *word, int *inputCodePoints) const;
     int getBigramListPositionForWord(const int *prevWord, const int prevWordLength,
             const bool forceLowerCaseSearch) const;
 
-    const uint8_t *const DICT_ROOT;
+    const BinaryDictionaryInfo *const mBinaryDictionaryInfo;
     // TODO: Re-implement proximity correction for bigram correction
     static const int MAX_ALTERNATIVES = 1;
 };
diff --git a/native/jni/src/suggest/core/dicnode/dic_node_utils.cpp b/native/jni/src/suggest/core/dicnode/dic_node_utils.cpp
index 6787efff5..46dbe4364 100644
--- a/native/jni/src/suggest/core/dicnode/dic_node_utils.cpp
+++ b/native/jni/src/suggest/core/dicnode/dic_node_utils.cpp
@@ -20,6 +20,7 @@
 #include "suggest/core/dicnode/dic_node.h"
 #include "suggest/core/dicnode/dic_node_utils.h"
 #include "suggest/core/dicnode/dic_node_vector.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 #include "suggest/core/dictionary/char_utils.h"
 #include "suggest/core/dictionary/multi_bigram_map.h"
@@ -33,20 +34,23 @@ namespace latinime {
 // Node initialization utils //
 ///////////////////////////////
 
-/* static */ void DicNodeUtils::initAsRoot(const int rootPos, const uint8_t *const dicRoot,
-        const int prevWordNodePos, DicNode *newRootNode) {
-    int curPos = rootPos;
+/* static */ void DicNodeUtils::initAsRoot(const BinaryDictionaryInfo *const binaryDictionaryInfo,
+        const int prevWordNodePos, DicNode *const newRootNode) {
+    int curPos = binaryDictionaryInfo->getRootPosition();
     const int pos = curPos;
-    const int childrenCount = BinaryFormat::getGroupCountAndForwardPointer(dicRoot, &curPos);
+    const int childrenCount = BinaryFormat::getGroupCountAndForwardPointer(
+            binaryDictionaryInfo->getDictRoot(), &curPos);
     const int childrenPos = curPos;
     newRootNode->initAsRoot(pos, childrenPos, childrenCount, prevWordNodePos);
 }
 
-/*static */ void DicNodeUtils::initAsRootWithPreviousWord(const int rootPos,
-        const uint8_t *const dicRoot, DicNode *prevWordLastNode, DicNode *newRootNode) {
-    int curPos = rootPos;
+/*static */ void DicNodeUtils::initAsRootWithPreviousWord(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo,
+        DicNode *const prevWordLastNode, DicNode *const newRootNode) {
+    int curPos = binaryDictionaryInfo->getRootPosition();
     const int pos = curPos;
-    const int childrenCount = BinaryFormat::getGroupCountAndForwardPointer(dicRoot, &curPos);
+    const int childrenCount = BinaryFormat::getGroupCountAndForwardPointer(
+            binaryDictionaryInfo->getDictRoot(), &curPos);
     const int childrenPos = curPos;
     newRootNode->initAsRootWithPreviousWord(prevWordLastNode, pos, childrenPos, childrenCount);
 }
@@ -72,16 +76,19 @@ namespace latinime {
 }
 
 /* static */ int DicNodeUtils::createAndGetLeavingChildNode(DicNode *dicNode, int pos,
-        const uint8_t *const dicRoot, const int terminalDepth, const ProximityInfoState *pInfoState,
-        const int pointIndex, const bool exactOnly, const std::vector<int> *const codePointsFilter,
-        const ProximityInfo *const pInfo, DicNodeVector *childDicNodes) {
+        const BinaryDictionaryInfo *const binaryDictionaryInfo, const int terminalDepth,
+        const ProximityInfoState *pInfoState, const int pointIndex, const bool exactOnly,
+        const std::vector<int> *const codePointsFilter, const ProximityInfo *const pInfo,
+        DicNodeVector *childDicNodes) {
     int nextPos = pos;
-    const uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(dicRoot, &pos);
+    const uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(
+            binaryDictionaryInfo->getDictRoot(), &pos);
     const bool hasMultipleChars = (0 != (BinaryFormat::FLAG_HAS_MULTIPLE_CHARS & flags));
     const bool isTerminal = (0 != (BinaryFormat::FLAG_IS_TERMINAL & flags));
     const bool hasChildren = BinaryFormat::hasChildrenInFlags(flags);
 
-    int codePoint = BinaryFormat::getCodePointAndForwardPointer(dicRoot, &pos);
+    int codePoint = BinaryFormat::getCodePointAndForwardPointer(
+            binaryDictionaryInfo->getDictRoot(), &pos);
     ASSERT(NOT_A_CODE_POINT != codePoint);
     const int nodeCodePoint = codePoint;
     // TODO: optimize this
@@ -91,7 +98,8 @@ namespace latinime {
 
     do {
         const int nextCodePoint = hasMultipleChars
-                ? BinaryFormat::getCodePointAndForwardPointer(dicRoot, &pos) : NOT_A_CODE_POINT;
+                ? BinaryFormat::getCodePointAndForwardPointer(
+                        binaryDictionaryInfo->getDictRoot(), &pos) : NOT_A_CODE_POINT;
         const bool isLastChar = (NOT_A_CODE_POINT == nextCodePoint);
         if (!isLastChar) {
             additionalWordBuf[additionalSubwordLength++] = nextCodePoint;
@@ -99,12 +107,14 @@ namespace latinime {
         codePoint = nextCodePoint;
     } while (NOT_A_CODE_POINT != codePoint);
 
-    const int probability =
-            isTerminal ? BinaryFormat::readProbabilityWithoutMovingPointer(dicRoot, pos) : -1;
+    const int probability = isTerminal ? BinaryFormat::readProbabilityWithoutMovingPointer(
+            binaryDictionaryInfo->getDictRoot(), pos) : -1;
     pos = BinaryFormat::skipProbability(flags, pos);
-    int childrenPos = hasChildren ? BinaryFormat::readChildrenPosition(dicRoot, flags, pos) : 0;
+    int childrenPos = hasChildren ? BinaryFormat::readChildrenPosition(
+            binaryDictionaryInfo->getDictRoot(), flags, pos) : 0;
     const int attributesPos = BinaryFormat::skipChildrenPosition(flags, pos);
-    const int siblingPos = BinaryFormat::skipChildrenPosAndAttributes(dicRoot, flags, pos);
+    const int siblingPos = BinaryFormat::skipChildrenPosAndAttributes(
+            binaryDictionaryInfo->getDictRoot(), flags, pos);
 
     if (isDicNodeFilteredOut(nodeCodePoint, pInfo, codePointsFilter)) {
         return siblingPos;
@@ -112,8 +122,8 @@ namespace latinime {
     if (!isMatchedNodeCodePoint(pInfoState, pointIndex, exactOnly, nodeCodePoint)) {
         return siblingPos;
     }
-    const int childrenCount = hasChildren
-            ? BinaryFormat::getGroupCountAndForwardPointer(dicRoot, &childrenPos) : 0;
+    const int childrenCount = hasChildren ? BinaryFormat::getGroupCountAndForwardPointer(
+            binaryDictionaryInfo->getDictRoot(), &childrenPos) : 0;
     childDicNodes->pushLeavingChild(dicNode, nextPos, flags, childrenPos, attributesPos, siblingPos,
             nodeCodePoint, childrenCount, probability, -1 /* bigramProbability */, isTerminal,
             hasMultipleChars, hasChildren, additionalSubwordLength, additionalWordBuf);
@@ -149,16 +159,18 @@ namespace latinime {
 }
 
 /* static */ void DicNodeUtils::createAndGetAllLeavingChildNodes(DicNode *dicNode,
-        const uint8_t *const dicRoot, const ProximityInfoState *pInfoState, const int pointIndex,
-        const bool exactOnly, const std::vector<int> *const codePointsFilter,
-        const ProximityInfo *const pInfo, DicNodeVector *childDicNodes) {
+        const BinaryDictionaryInfo *const binaryDictionaryInfo,
+        const ProximityInfoState *pInfoState, const int pointIndex, const bool exactOnly,
+        const std::vector<int> *const codePointsFilter, const ProximityInfo *const pInfo,
+        DicNodeVector *childDicNodes) {
     const int terminalDepth = dicNode->getLeavingDepth();
     const int childCount = dicNode->getChildrenCount();
     int nextPos = dicNode->getChildrenPos();
     for (int i = 0; i < childCount; i++) {
         const int filterSize = codePointsFilter ? codePointsFilter->size() : 0;
-        nextPos = createAndGetLeavingChildNode(dicNode, nextPos, dicRoot, terminalDepth, pInfoState,
-                pointIndex, exactOnly, codePointsFilter, pInfo, childDicNodes);
+        nextPos = createAndGetLeavingChildNode(dicNode, nextPos, binaryDictionaryInfo,
+                terminalDepth, pInfoState, pointIndex, exactOnly, codePointsFilter, pInfo,
+                childDicNodes);
         if (!pInfo && filterSize > 0 && childDicNodes->exceeds(filterSize)) {
             // All code points have been found.
             break;
@@ -166,14 +178,15 @@ namespace latinime {
     }
 }
 
-/* static */ void DicNodeUtils::getAllChildDicNodes(DicNode *dicNode, const uint8_t *const dicRoot,
-        DicNodeVector *childDicNodes) {
-    getProximityChildDicNodes(dicNode, dicRoot, 0, 0, false, childDicNodes);
+/* static */ void DicNodeUtils::getAllChildDicNodes(DicNode *dicNode,
+        const BinaryDictionaryInfo *const binaryDictionaryInfo, DicNodeVector *childDicNodes) {
+    getProximityChildDicNodes(dicNode, binaryDictionaryInfo, 0, 0, false, childDicNodes);
 }
 
 /* static */ void DicNodeUtils::getProximityChildDicNodes(DicNode *dicNode,
-        const uint8_t *const dicRoot, const ProximityInfoState *pInfoState, const int pointIndex,
-        bool exactOnly, DicNodeVector *childDicNodes) {
+        const BinaryDictionaryInfo *const binaryDictionaryInfo,
+        const ProximityInfoState *pInfoState, const int pointIndex, bool exactOnly,
+        DicNodeVector *childDicNodes) {
     if (dicNode->isTotalInputSizeExceedingLimit()) {
         return;
     }
@@ -181,9 +194,9 @@ namespace latinime {
         DicNodeUtils::createAndGetPassingChildNode(dicNode, pInfoState, pointIndex, exactOnly,
                 childDicNodes);
     } else {
-        DicNodeUtils::createAndGetAllLeavingChildNodes(dicNode, dicRoot, pInfoState, pointIndex,
-                exactOnly, 0 /* codePointsFilter */, 0 /* pInfo */,
-                childDicNodes);
+        DicNodeUtils::createAndGetAllLeavingChildNodes(
+                dicNode, binaryDictionaryInfo, pInfoState, pointIndex, exactOnly,
+                0 /* codePointsFilter */, 0 /* pInfo */, childDicNodes);
     }
 }
 
@@ -193,19 +206,21 @@ namespace latinime {
 /**
  * Computes the combined bigram / unigram cost for the given dicNode.
  */
-/* static */ float DicNodeUtils::getBigramNodeImprobability(const uint8_t *const dicRoot,
+/* static */ float DicNodeUtils::getBigramNodeImprobability(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo,
         const DicNode *const node, MultiBigramMap *multiBigramMap) {
     if (node->isImpossibleBigramWord()) {
         return static_cast<float>(MAX_VALUE_FOR_WEIGHTING);
     }
-    const int probability = getBigramNodeProbability(dicRoot, node, multiBigramMap);
+    const int probability = getBigramNodeProbability(binaryDictionaryInfo, node, multiBigramMap);
     // TODO: This equation to calculate the improbability looks unreasonable.  Investigate this.
     const float cost = static_cast<float>(MAX_PROBABILITY - probability)
             / static_cast<float>(MAX_PROBABILITY);
     return cost;
 }
 
-/* static */ int DicNodeUtils::getBigramNodeProbability(const uint8_t *const dicRoot,
+/* static */ int DicNodeUtils::getBigramNodeProbability(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo,
         const DicNode *const node, MultiBigramMap *multiBigramMap) {
     const int unigramProbability = node->getProbability();
     const int wordPos = node->getPos();
@@ -216,9 +231,10 @@ namespace latinime {
     }
     if (multiBigramMap) {
         return multiBigramMap->getBigramProbability(
-                dicRoot, prevWordPos, wordPos, unigramProbability);
+                binaryDictionaryInfo, prevWordPos, wordPos, unigramProbability);
     }
-    return BinaryFormat::getBigramProbability(dicRoot, prevWordPos, wordPos, unigramProbability);
+    return BinaryFormat::getBigramProbability(
+            binaryDictionaryInfo->getDictRoot(), prevWordPos, wordPos, unigramProbability);
 }
 
 ///////////////////////////////////////
diff --git a/native/jni/src/suggest/core/dicnode/dic_node_utils.h b/native/jni/src/suggest/core/dicnode/dic_node_utils.h
index 5bc542d05..e198d6181 100644
--- a/native/jni/src/suggest/core/dicnode/dic_node_utils.h
+++ b/native/jni/src/suggest/core/dicnode/dic_node_utils.h
@@ -24,6 +24,7 @@
 
 namespace latinime {
 
+class BinaryDictionaryInfo;
 class DicNode;
 class DicNodeVector;
 class ProximityInfo;
@@ -34,19 +35,20 @@ class DicNodeUtils {
  public:
     static int appendTwoWords(const int *src0, const int16_t length0, const int *src1,
             const int16_t length1, int *dest);
-    static void initAsRoot(const int rootPos, const uint8_t *const dicRoot,
+    static void initAsRoot(const BinaryDictionaryInfo *const binaryDictionaryInfo,
             const int prevWordNodePos, DicNode *newRootNode);
-    static void initAsRootWithPreviousWord(const int rootPos, const uint8_t *const dicRoot,
+    static void initAsRootWithPreviousWord(const BinaryDictionaryInfo *const binaryDictionaryInfo,
             DicNode *prevWordLastNode, DicNode *newRootNode);
     static void initByCopy(DicNode *srcNode, DicNode *destNode);
-    static void getAllChildDicNodes(DicNode *dicNode, const uint8_t *const dicRoot,
-            DicNodeVector *childDicNodes);
-    static float getBigramNodeImprobability(const uint8_t *const dicRoot,
+    static void getAllChildDicNodes(DicNode *dicNode,
+            const BinaryDictionaryInfo *const binaryDictionaryInfo, DicNodeVector *childDicNodes);
+    static float getBigramNodeImprobability(const BinaryDictionaryInfo *const binaryDictionaryInfo,
             const DicNode *const node, MultiBigramMap *const multiBigramMap);
     static bool isDicNodeFilteredOut(const int nodeCodePoint, const ProximityInfo *const pInfo,
             const std::vector<int> *const codePointsFilter);
     // TODO: Move to private
-    static void getProximityChildDicNodes(DicNode *dicNode, const uint8_t *const dicRoot,
+    static void getProximityChildDicNodes(DicNode *dicNode,
+            const BinaryDictionaryInfo *const binaryDictionaryInfo,
             const ProximityInfoState *pInfoState, const int pointIndex, bool exactOnly,
             DicNodeVector *childDicNodes);
 
@@ -60,16 +62,18 @@ class DicNodeUtils {
     // Max number of bigrams to look up
     static const int MAX_BIGRAMS_CONSIDERED_PER_CONTEXT = 500;
 
-    static int getBigramNodeProbability(const uint8_t *const dicRoot, const DicNode *const node,
-            MultiBigramMap *multiBigramMap);
+    static int getBigramNodeProbability(const BinaryDictionaryInfo *const binaryDictionaryInfo,
+            const DicNode *const node, MultiBigramMap *multiBigramMap);
     static void createAndGetPassingChildNode(DicNode *dicNode, const ProximityInfoState *pInfoState,
             const int pointIndex, const bool exactOnly, DicNodeVector *childDicNodes);
-    static void createAndGetAllLeavingChildNodes(DicNode *dicNode, const uint8_t *const dicRoot,
+    static void createAndGetAllLeavingChildNodes(DicNode *dicNode,
+            const BinaryDictionaryInfo *const binaryDictionaryInfo,
             const ProximityInfoState *pInfoState, const int pointIndex, const bool exactOnly,
             const std::vector<int> *const codePointsFilter,
             const ProximityInfo *const pInfo, DicNodeVector *childDicNodes);
-    static int createAndGetLeavingChildNode(DicNode *dicNode, int pos, const uint8_t *const dicRoot,
-            const int terminalDepth, const ProximityInfoState *pInfoState, const int pointIndex,
+    static int createAndGetLeavingChildNode(DicNode *dicNode, int pos,
+            const BinaryDictionaryInfo *const binaryDictionaryInfo, const int terminalDepth,
+            const ProximityInfoState *pInfoState, const int pointIndex,
             const bool exactOnly, const std::vector<int> *const codePointsFilter,
             const ProximityInfo *const pInfo, DicNodeVector *childDicNodes);
 
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_format.cpp b/native/jni/src/suggest/core/dictionary/binary_dictionary_format.cpp
new file mode 100644
index 000000000..50e0211d7
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_format.cpp
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "suggest/core/dictionary/binary_dictionary_format.h"
+
+namespace latinime {
+
+/**
+ * Dictionary size
+ */
+// Any file smaller than this is not a dictionary.
+const int BinaryDictionaryFormat::DICTIONARY_MINIMUM_SIZE = 4;
+
+/**
+ * Format versions
+ */
+// Originally, format version 1 had a 16-bit magic number, then the version number `01'
+// then options that must be 0. Hence the first 32-bits of the format are always as follow
+// and it's okay to consider them a magic number as a whole.
+const uint32_t BinaryDictionaryFormat::FORMAT_VERSION_1_MAGIC_NUMBER = 0x78B10100;
+const int BinaryDictionaryFormat::FORMAT_VERSION_1_HEADER_SIZE = 5;
+
+// The versions of Latin IME that only handle format version 1 only test for the magic
+// number, so we had to change it so that version 2 files would be rejected by older
+// implementations. On this occasion, we made the magic number 32 bits long.
+const uint32_t BinaryDictionaryFormat::FORMAT_VERSION_2_MAGIC_NUMBER = 0x9BC13AFE;
+// Magic number (4 bytes), version (2 bytes), options (2 bytes), header size (4 bytes) = 12
+const int BinaryDictionaryFormat::FORMAT_VERSION_2_MINIMUM_SIZE = 12;
+const int BinaryDictionaryFormat::VERSION_2_MAGIC_NUMBER_SIZE = 4;
+const int BinaryDictionaryFormat::VERSION_2_DICTIONARY_VERSION_SIZE = 2;
+const int BinaryDictionaryFormat::VERSION_2_DICTIONARY_FLAG_SIZE = 2;
+
+/* static */ BinaryDictionaryFormat::FORMAT_VERSION BinaryDictionaryFormat::detectFormatVersion(
+        const uint8_t *const dict, const int dictSize) {
+    // The magic number is stored big-endian.
+    // If the dictionary is less than 4 bytes, we can't even read the magic number, so we don't
+    // understand this format.
+    if (dictSize < DICTIONARY_MINIMUM_SIZE) {
+        return UNKNOWN_VERSION;
+    }
+    const uint32_t magicNumber = ByteArrayUtils::readUint32(dict, 0);
+    switch (magicNumber) {
+    case FORMAT_VERSION_1_MAGIC_NUMBER:
+        // Format 1 header is exactly 5 bytes long and looks like:
+        // Magic number (2 bytes) 0x78 0xB1
+        // Version number (1 byte) 0x01
+        // Options (2 bytes) must be 0x00 0x00
+        return VERSION_1;
+    case FORMAT_VERSION_2_MAGIC_NUMBER:
+        // Version 2 dictionaries are at least 12 bytes long.
+        // If this dictionary has the version 2 magic number but is less than 12 bytes long,
+        // then it's an unknown format and we need to avoid confidently reading the next bytes.
+        if (dictSize < FORMAT_VERSION_2_MINIMUM_SIZE) {
+            return UNKNOWN_VERSION;
+        }
+        // Format 2 header is as follows:
+        // Magic number (4 bytes) 0x9B 0xC1 0x3A 0xFE
+        // Version number (2 bytes) 0x00 0x02
+        // Options (2 bytes)
+        // Header size (4 bytes) : integer, big endian
+        if (ByteArrayUtils::readUint16(dict, 4) == 2) {
+            return VERSION_2;
+        } else {
+            return UNKNOWN_VERSION;
+        }
+    default:
+        return UNKNOWN_VERSION;
+    }
+}
+
+} // namespace latinime
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_format.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_format.h
new file mode 100644
index 000000000..3aa1662da
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_format.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef LATINIME_BINARY_DICTIONARY_FORMAT_H
+#define LATINIME_BINARY_DICTIONARY_FORMAT_H
+
+#include <stdint.h>
+
+#include "defines.h"
+#include "suggest/core/dictionary/byte_array_utils.h"
+
+namespace latinime {
+
+/**
+ * Methods to handle binary dictionary format version.
+ *
+ * Currently, we have a file with a similar name, binary_format.h. binary_format.h contains binary
+ * reading methods and utility methods for various purposes.
+ * On the other hand, this file deals with only about dictionary format version.
+ */
+class BinaryDictionaryFormat {
+ public:
+    // TODO: Remove obsolete version logic
+    enum FORMAT_VERSION {
+        VERSION_1,
+        VERSION_2,
+        UNKNOWN_VERSION
+    };
+
+    static FORMAT_VERSION detectFormatVersion(const uint8_t *const dict, const int dictSize);
+
+    static AK_FORCE_INLINE int getHeaderSize(
+            const uint8_t *const dict, const FORMAT_VERSION format) {
+        switch (format) {
+        case VERSION_1:
+            return FORMAT_VERSION_1_HEADER_SIZE;
+        case VERSION_2:
+            // See the format of the header in the comment in detectFormat() above
+            return ByteArrayUtils::readUint32(dict, 8);
+        default:
+            return S_INT_MAX;
+        }
+    }
+
+ private:
+    DISALLOW_IMPLICIT_CONSTRUCTORS(BinaryDictionaryFormat);
+
+    static const int DICTIONARY_MINIMUM_SIZE;
+    static const uint32_t FORMAT_VERSION_1_MAGIC_NUMBER;
+    static const int FORMAT_VERSION_1_HEADER_SIZE;
+    static const uint32_t FORMAT_VERSION_2_MAGIC_NUMBER;
+    static const int FORMAT_VERSION_2_MINIMUM_SIZE;
+    static const int VERSION_2_MAGIC_NUMBER_SIZE;
+    static const int VERSION_2_DICTIONARY_VERSION_SIZE ;
+    static const int VERSION_2_DICTIONARY_FLAG_SIZE;
+};
+} // namespace latinime
+#endif /* LATINIME_BINARY_DICTIONARY_FORMAT_H */
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
new file mode 100644
index 000000000..8508c6786
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef LATINIME_BINARY_DICTIONARY_INFO_H
+#define LATINIME_BINARY_DICTIONARY_INFO_H
+
+#include <stdint.h>
+
+#include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_format.h"
+
+namespace latinime {
+
+class BinaryDictionaryInfo {
+ public:
+    BinaryDictionaryInfo(const uint8_t *const dictBuf, const int dictSize)
+            : mDictBuf(dictBuf),
+              mFormat(BinaryDictionaryFormat::detectFormatVersion(mDictBuf, dictSize)),
+              mDictRoot(mDictBuf + BinaryDictionaryFormat::getHeaderSize(mDictBuf, mFormat)) {}
+
+    AK_FORCE_INLINE const uint8_t *getDictBuf() const {
+        return mDictBuf;
+    }
+
+    AK_FORCE_INLINE const uint8_t *getDictRoot() const {
+        return mDictRoot;
+    }
+
+    AK_FORCE_INLINE BinaryDictionaryFormat::FORMAT_VERSION getFormat() const {
+        return mFormat;
+    }
+
+    AK_FORCE_INLINE int getRootPosition() const {
+        return 0;
+    }
+
+ private:
+    DISALLOW_COPY_AND_ASSIGN(BinaryDictionaryInfo);
+
+    const uint8_t *const mDictBuf;
+    const BinaryDictionaryFormat::FORMAT_VERSION mFormat;
+    const uint8_t *const mDictRoot;
+};
+}
+#endif /* LATINIME_BINARY_DICTIONARY_INFO_H */
diff --git a/native/jni/src/suggest/core/dictionary/byte_array_utils.cpp b/native/jni/src/suggest/core/dictionary/byte_array_utils.cpp
new file mode 100644
index 000000000..68b1d5d15
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/byte_array_utils.cpp
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "suggest/core/dictionary/byte_array_utils.h"
+
+namespace latinime {
+
+const uint8_t ByteArrayUtils::MINIMAL_ONE_BYTE_CHARACTER_VALUE = 0x20;
+const uint8_t ByteArrayUtils::CHARACTER_ARRAY_TERMINATOR = 0x1F;
+
+} // namespace latinime
diff --git a/native/jni/src/suggest/core/dictionary/byte_array_utils.h b/native/jni/src/suggest/core/dictionary/byte_array_utils.h
new file mode 100644
index 000000000..832b74725
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/byte_array_utils.h
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef LATINIME_BYTE_ARRAY_UTILS_H
+#define LATINIME_BYTE_ARRAY_UTILS_H
+
+#include <stdint.h>
+
+#include "defines.h"
+
+namespace latinime {
+
+/**
+ * Utility methods for reading byte arrays.
+ */
+class ByteArrayUtils {
+ public:
+    /**
+     * Integer
+     *
+     * Each method read a corresponding size integer in a big endian manner.
+     */
+    static AK_FORCE_INLINE uint32_t readUint32(const uint8_t *const buffer, const int pos) {
+        return (buffer[pos] << 24) ^ (buffer[pos + 1] << 16)
+                ^ (buffer[pos + 2] << 8) ^ buffer[pos + 3];
+    }
+
+    static AK_FORCE_INLINE uint32_t readUint24(const uint8_t *const buffer, const int pos) {
+        return (buffer[pos] << 16) ^ (buffer[pos + 1] << 8) ^ buffer[pos + 2];
+    }
+
+    static AK_FORCE_INLINE uint16_t readUint16(const uint8_t *const buffer, const int pos) {
+        return (buffer[pos] << 8) ^ buffer[pos + 1];
+    }
+
+    static AK_FORCE_INLINE uint8_t readUint8(const uint8_t *const buffer, const int pos) {
+        return buffer[pos];
+    }
+
+    static AK_FORCE_INLINE uint32_t readUint32andAdvancePosition(
+            const uint8_t *const buffer, int *const pos) {
+        const uint32_t value = readUint32(buffer, *pos);
+        *pos += 4;
+        return value;
+    }
+
+    static AK_FORCE_INLINE uint32_t readUint24andAdvancePosition(
+            const uint8_t *const buffer, int *const pos) {
+        const uint32_t value = readUint24(buffer, *pos);
+        *pos += 3;
+        return value;
+    }
+
+    static AK_FORCE_INLINE uint16_t readUint16andAdvancePosition(
+            const uint8_t *const buffer, int *const pos) {
+        const uint16_t value = readUint16(buffer, *pos);
+        *pos += 2;
+        return value;
+    }
+
+    static AK_FORCE_INLINE uint8_t readUint8andAdvancePosition(
+            const uint8_t *const buffer, int *const pos) {
+        return buffer[(*pos)++];
+    }
+
+    /**
+     * Code Point
+     *
+     * 1 byte = bbbbbbbb match
+     * case 000xxxxx: xxxxx << 16 + next byte << 8 + next byte
+     * else: if 00011111 (= 0x1F) : this is the terminator. This is a relevant choice because
+     *       unicode code points range from 0 to 0x10FFFF, so any 3-byte value starting with
+     *       00011111 would be outside unicode.
+     * else: iso-latin-1 code
+     * This allows for the whole unicode range to be encoded, including chars outside of
+     * the BMP. Also everything in the iso-latin-1 charset is only 1 byte, except control
+     * characters which should never happen anyway (and still work, but take 3 bytes).
+     */
+    static AK_FORCE_INLINE int readCodePoint(const uint8_t *const buffer, const int pos) {
+        int p = pos;
+        return readCodePointAndAdvancePosition(buffer, &p);
+    }
+
+    static AK_FORCE_INLINE int readCodePointAndAdvancePosition(
+            const uint8_t *const buffer, int *const pos) {
+        const uint8_t firstByte = readUint8(buffer, *pos);
+        if (firstByte < MINIMAL_ONE_BYTE_CHARACTER_VALUE) {
+            if (firstByte == CHARACTER_ARRAY_TERMINATOR) {
+                *pos += 1;
+                return NOT_A_CODE_POINT;
+            } else {
+                return readUint24andAdvancePosition(buffer, pos);
+            }
+        } else {
+            *pos += 1;
+            return firstByte;
+        }
+    }
+
+    /**
+     * String (array of code points)
+     *
+     * Reads code points until the terminator is found.
+     */
+    // Returns the length of the string.
+    static int readStringAndAdvancePosition(const uint8_t *const buffer, int *const pos,
+            int *const outBuffer, const int maxLength) {
+        int length = 0;
+        int codePoint = readCodePointAndAdvancePosition(buffer, pos);
+        while (NOT_A_CODE_POINT != codePoint && length < maxLength) {
+            outBuffer[length++] = codePoint;
+            codePoint = readCodePointAndAdvancePosition(buffer, pos);
+        }
+        return length;
+    }
+
+    // Advances the position and returns the length of the string.
+    static int advancePositionToBehindString(
+            const uint8_t *const buffer, int *const pos, const int maxLength) {
+        int length = 0;
+        int codePoint = readCodePointAndAdvancePosition(buffer, pos);
+        while (NOT_A_CODE_POINT != codePoint && length < maxLength) {
+            codePoint = readCodePointAndAdvancePosition(buffer, pos);
+        }
+        return length;
+    }
+
+ private:
+    DISALLOW_IMPLICIT_CONSTRUCTORS(ByteArrayUtils);
+
+    static const uint8_t MINIMAL_ONE_BYTE_CHARACTER_VALUE;
+    static const uint8_t CHARACTER_ARRAY_TERMINATOR;
+};
+} // namespace latinime
+#endif /* LATINIME_BYTE_ARRAY_UTILS_H */
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.cpp b/native/jni/src/suggest/core/dictionary/dictionary.cpp
index 1939c7420..53a6751d2 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary.cpp
@@ -34,13 +34,11 @@
 namespace latinime {
 
 Dictionary::Dictionary(void *dict, int dictSize, int mmapFd, int dictBufAdjust)
-        : mDict(static_cast<unsigned char *>(dict)),
-          mOffsetDict((static_cast<unsigned char *>(dict))
-                  + BinaryFormat::getHeaderSize(mDict, dictSize)),
+        : mBinaryDicitonaryInfo(static_cast<const uint8_t *>(dict), dictSize),
           mDictSize(dictSize), mMmapFd(mmapFd), mDictBufAdjust(dictBufAdjust),
-          mUnigramDictionary(new UnigramDictionary(mOffsetDict,
-                  BinaryFormat::getFlags(mDict, dictSize))),
-          mBigramDictionary(new BigramDictionary(mOffsetDict)),
+          mUnigramDictionary(new UnigramDictionary(&mBinaryDicitonaryInfo,
+                  BinaryFormat::getFlags(mBinaryDicitonaryInfo.getDictBuf(), dictSize))),
+          mBigramDictionary(new BigramDictionary(&mBinaryDicitonaryInfo)),
           mGestureSuggest(new Suggest(GestureSuggestPolicyFactory::getGestureSuggestPolicy())),
           mTypingSuggest(new Suggest(TypingSuggestPolicyFactory::getTypingSuggestPolicy())) {
 }
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.h b/native/jni/src/suggest/core/dictionary/dictionary.h
index e6861a3dd..771837bc6 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.h
+++ b/native/jni/src/suggest/core/dictionary/dictionary.h
@@ -20,6 +20,7 @@
 #include <stdint.h>
 
 #include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 
 namespace latinime {
 
@@ -64,11 +65,8 @@ class Dictionary {
 
     int getProbability(const int *word, int length) const;
     bool isValidBigram(const int *word1, int length1, const int *word2, int length2) const;
-    const uint8_t *getDict() const { // required to release dictionary buffer
-        return mDict;
-    }
-    const uint8_t *getOffsetDict() const {
-        return mOffsetDict;
+    const BinaryDictionaryInfo *getBinaryDictionaryInfo() const {
+        return &mBinaryDicitonaryInfo;
     }
     int getDictSize() const { return mDictSize; }
     int getMmapFd() const { return mMmapFd; }
@@ -78,9 +76,8 @@ class Dictionary {
 
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(Dictionary);
-    const uint8_t *mDict;
-    const uint8_t *mOffsetDict;
 
+    const BinaryDictionaryInfo mBinaryDicitonaryInfo;
     // Used only for the mmap version of dictionary loading, but we use these as dummy variables
     // also for the malloc version.
     const int mDictSize;
diff --git a/native/jni/src/suggest/core/dictionary/multi_bigram_map.h b/native/jni/src/suggest/core/dictionary/multi_bigram_map.h
index fcac98f35..b17c75803 100644
--- a/native/jni/src/suggest/core/dictionary/multi_bigram_map.h
+++ b/native/jni/src/suggest/core/dictionary/multi_bigram_map.h
@@ -17,10 +17,9 @@
 #ifndef LATINIME_MULTI_BIGRAM_MAP_H
 #define LATINIME_MULTI_BIGRAM_MAP_H
 
-#include <stdint.h>
-
 #include "defines.h"
 #include "hash_map_compat.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 
 namespace latinime {
@@ -35,20 +34,20 @@ class MultiBigramMap {
 
     // Look up the bigram probability for the given word pair from the cached bigram maps.
     // Also caches the bigrams if there is space remaining and they have not been cached already.
-    int getBigramProbability(const uint8_t *const dicRoot, const int wordPosition,
-            const int nextWordPosition, const int unigramProbability) {
+    int getBigramProbability(const BinaryDictionaryInfo *const binaryDicitonaryInfo,
+            const int wordPosition, const int nextWordPosition, const int unigramProbability) {
         hash_map_compat<int, BigramMap>::const_iterator mapPosition =
                 mBigramMaps.find(wordPosition);
         if (mapPosition != mBigramMaps.end()) {
             return mapPosition->second.getBigramProbability(nextWordPosition, unigramProbability);
         }
         if (mBigramMaps.size() < MAX_CACHED_PREV_WORDS_IN_BIGRAM_MAP) {
-            addBigramsForWordPosition(dicRoot, wordPosition);
+            addBigramsForWordPosition(binaryDicitonaryInfo, wordPosition);
             return mBigramMaps[wordPosition].getBigramProbability(
                     nextWordPosition, unigramProbability);
         }
-        return BinaryFormat::getBigramProbability(
-                dicRoot, wordPosition, nextWordPosition, unigramProbability);
+        return BinaryFormat::getBigramProbability(binaryDicitonaryInfo->getDictRoot(),
+                wordPosition, nextWordPosition, unigramProbability);
     }
 
     void clear() {
@@ -63,8 +62,9 @@ class MultiBigramMap {
         BigramMap() : mBigramMap(DEFAULT_HASH_MAP_SIZE_FOR_EACH_BIGRAM_MAP) {}
         ~BigramMap() {}
 
-        void init(const uint8_t *const dicRoot, int position) {
-            BinaryFormat::fillBigramProbabilityToHashMap(dicRoot, position, &mBigramMap);
+        void init(const BinaryDictionaryInfo *const binaryDicitonaryInfo, const int position) {
+            BinaryFormat::fillBigramProbabilityToHashMap(
+                    binaryDicitonaryInfo->getDictRoot(), position, &mBigramMap);
         }
 
         inline int getBigramProbability(const int nextWordPosition, const int unigramProbability)
@@ -78,8 +78,9 @@ class MultiBigramMap {
         hash_map_compat<int, int> mBigramMap;
     };
 
-    void addBigramsForWordPosition(const uint8_t *const dicRoot, const int position) {
-        mBigramMaps[position].init(dicRoot, position);
+    void addBigramsForWordPosition(const BinaryDictionaryInfo *const binaryDicitonaryInfo,
+            const int position) {
+        mBigramMaps[position].init(binaryDicitonaryInfo, position);
     }
 
     hash_map_compat<int, BigramMap> mBigramMaps;
diff --git a/native/jni/src/suggest/core/dictionary/terminal_attributes.h b/native/jni/src/suggest/core/dictionary/terminal_attributes.h
index 8377c603d..bbd9af090 100644
--- a/native/jni/src/suggest/core/dictionary/terminal_attributes.h
+++ b/native/jni/src/suggest/core/dictionary/terminal_attributes.h
@@ -19,6 +19,7 @@
 
 #include <stdint.h>
 
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 
 namespace latinime {
@@ -32,8 +33,9 @@ class TerminalAttributes {
  public:
     class ShortcutIterator {
      public:
-        ShortcutIterator(const uint8_t *dict, const int pos, const uint8_t flags)
-                : mDict(dict), mPos(pos),
+        ShortcutIterator(const BinaryDictionaryInfo *const binaryDictionaryInfo, const int pos,
+                const uint8_t flags)
+                : mBinaryDicitionaryInfo(binaryDictionaryInfo), mPos(pos),
                   mHasNextShortcutTarget(0 != (flags & BinaryFormat::FLAG_HAS_SHORTCUT_TARGETS)) {
         }
 
@@ -44,11 +46,13 @@ class TerminalAttributes {
         // Gets the shortcut target itself as an int string. For parameters and return value
         // see BinaryFormat::getWordAtAddress.
         inline int getNextShortcutTarget(const int maxDepth, int *outWord, int *outFreq) {
-            const int shortcutFlags = BinaryFormat::getFlagsAndForwardPointer(mDict, &mPos);
+            const int shortcutFlags = BinaryFormat::getFlagsAndForwardPointer(
+                    mBinaryDicitionaryInfo->getDictRoot(), &mPos);
             mHasNextShortcutTarget = 0 != (shortcutFlags & BinaryFormat::FLAG_ATTRIBUTE_HAS_NEXT);
             unsigned int i;
             for (i = 0; i < MAX_WORD_LENGTH; ++i) {
-                const int codePoint = BinaryFormat::getCodePointAndForwardPointer(mDict, &mPos);
+                const int codePoint = BinaryFormat::getCodePointAndForwardPointer(
+                        mBinaryDicitionaryInfo->getDictRoot(), &mPos);
                 if (NOT_A_CODE_POINT == codePoint) break;
                 outWord[i] = codePoint;
             }
@@ -57,19 +61,21 @@ class TerminalAttributes {
         }
 
      private:
-        const uint8_t *const mDict;
+        const BinaryDictionaryInfo *const mBinaryDicitionaryInfo;
         int mPos;
         bool mHasNextShortcutTarget;
     };
 
-    TerminalAttributes(const uint8_t *const dict, const uint8_t flags, const int pos)
-            : mDict(dict), mFlags(flags), mStartPos(pos) {
+    TerminalAttributes(const BinaryDictionaryInfo *const binaryDicitonaryInfo,
+            const uint8_t flags, const int pos)
+            : mBinaryDicitionaryInfo(binaryDicitonaryInfo), mFlags(flags), mStartPos(pos) {
     }
 
     inline ShortcutIterator getShortcutIterator() const {
         // The size of the shortcuts is stored here so that the whole shortcut chunk can be
         // skipped quickly, so we ignore it.
-        return ShortcutIterator(mDict, mStartPos + BinaryFormat::SHORTCUT_LIST_SIZE_SIZE, mFlags);
+        return ShortcutIterator(
+                mBinaryDicitionaryInfo, mStartPos + BinaryFormat::SHORTCUT_LIST_SIZE_SIZE, mFlags);
     }
 
     bool isBlacklistedOrNotAWord() const {
@@ -78,7 +84,7 @@ class TerminalAttributes {
 
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(TerminalAttributes);
-    const uint8_t *const mDict;
+    const BinaryDictionaryInfo *const mBinaryDicitionaryInfo;
     const uint8_t mFlags;
     const int mStartPos;
 };
diff --git a/native/jni/src/suggest/core/policy/weighting.cpp b/native/jni/src/suggest/core/policy/weighting.cpp
index 7ad568e25..0c57ca001 100644
--- a/native/jni/src/suggest/core/policy/weighting.cpp
+++ b/native/jni/src/suggest/core/policy/weighting.cpp
@@ -142,7 +142,7 @@ static inline void profile(const CorrectionType correctionType, DicNode *const n
     case CT_TERMINAL: {
         const float languageImprobability =
                 DicNodeUtils::getBigramNodeImprobability(
-                        traverseSession->getOffsetDict(), dicNode, multiBigramMap);
+                        traverseSession->getBinaryDictionaryInfo(), dicNode, multiBigramMap);
         return weighting->getTerminalLanguageCost(traverseSession, dicNode, languageImprobability);
     }
     case CT_NEW_WORD_SPACE_SUBSTITUTION:
diff --git a/native/jni/src/suggest/core/session/dic_traverse_session.cpp b/native/jni/src/suggest/core/session/dic_traverse_session.cpp
index 4e634500c..be293df42 100644
--- a/native/jni/src/suggest/core/session/dic_traverse_session.cpp
+++ b/native/jni/src/suggest/core/session/dic_traverse_session.cpp
@@ -20,6 +20,7 @@
 #include "dic_traverse_wrapper.h"
 #include "jni.h"
 #include "suggest/core/dicnode/dic_node_utils.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 #include "suggest/core/dictionary/dictionary.h"
 
@@ -65,7 +66,8 @@ static TraverseSessionFactoryRegisterer traverseSessionFactoryRegisterer;
 void DicTraverseSession::init(const Dictionary *const dictionary, const int *prevWord,
         int prevWordLength, const SuggestOptions *const suggestOptions) {
     mDictionary = dictionary;
-    mMultiWordCostMultiplier = BinaryFormat::getMultiWordCostMultiplier(mDictionary->getDict(),
+    mMultiWordCostMultiplier = BinaryFormat::getMultiWordCostMultiplier(
+            mDictionary->getBinaryDictionaryInfo()->getDictBuf(),
             mDictionary->getDictSize());
     mSuggestOptions = suggestOptions;
     if (!prevWord) {
@@ -73,12 +75,14 @@ void DicTraverseSession::init(const Dictionary *const dictionary, const int *pre
         return;
     }
     // TODO: merge following similar calls to getTerminalPosition into one case-insensitive call.
-    mPrevWordPos = BinaryFormat::getTerminalPosition(dictionary->getOffsetDict(), prevWord,
+    mPrevWordPos = BinaryFormat::getTerminalPosition(
+            dictionary->getBinaryDictionaryInfo()->getDictRoot(), prevWord,
             prevWordLength, false /* forceLowerCaseSearch */);
     if (mPrevWordPos == NOT_VALID_WORD) {
         // Check bigrams for lower-cased previous word if original was not found. Useful for
         // auto-capitalized words like "The [current_word]".
-        mPrevWordPos = BinaryFormat::getTerminalPosition(dictionary->getOffsetDict(), prevWord,
+        mPrevWordPos = BinaryFormat::getTerminalPosition(
+                dictionary->getBinaryDictionaryInfo()->getDictRoot(), prevWord,
                 prevWordLength, true /* forceLowerCaseSearch */);
     }
 }
@@ -93,8 +97,8 @@ void DicTraverseSession::setupForGetSuggestions(const ProximityInfo *pInfo,
             maxSpatialDistance, maxPointerCount);
 }
 
-const uint8_t *DicTraverseSession::getOffsetDict() const {
-    return mDictionary->getOffsetDict();
+const BinaryDictionaryInfo *DicTraverseSession::getBinaryDictionaryInfo() const {
+    return mDictionary->getBinaryDictionaryInfo();
 }
 
 int DicTraverseSession::getDictFlags() const {
diff --git a/native/jni/src/suggest/core/session/dic_traverse_session.h b/native/jni/src/suggest/core/session/dic_traverse_session.h
index e5c7f8e0c..3b6a3dc8c 100644
--- a/native/jni/src/suggest/core/session/dic_traverse_session.h
+++ b/native/jni/src/suggest/core/session/dic_traverse_session.h
@@ -28,6 +28,7 @@
 
 namespace latinime {
 
+class BinaryDictionaryInfo;
 class Dictionary;
 class ProximityInfo;
 class SuggestOptions;
@@ -56,7 +57,7 @@ class DicTraverseSession {
     void resetCache(const int nextActiveCacheSize, const int maxWords);
 
     // TODO: Remove
-    const uint8_t *getOffsetDict() const;
+    const BinaryDictionaryInfo *getBinaryDictionaryInfo() const;
     int getDictFlags() const;
 
     //--------------------
diff --git a/native/jni/src/suggest/core/suggest.cpp b/native/jni/src/suggest/core/suggest.cpp
index 720222363..1f108e400 100644
--- a/native/jni/src/suggest/core/suggest.cpp
+++ b/native/jni/src/suggest/core/suggest.cpp
@@ -105,8 +105,8 @@ void Suggest::initializeSearch(DicTraverseSession *traverseSession, int commitPo
         traverseSession->resetCache(TRAVERSAL->getMaxCacheSize(), MAX_RESULTS);
         // Create a new dic node here
         DicNode rootNode;
-        DicNodeUtils::initAsRoot(traverseSession->getDicRootPos(),
-                traverseSession->getOffsetDict(), traverseSession->getPrevWordPos(), &rootNode);
+        DicNodeUtils::initAsRoot(traverseSession->getBinaryDictionaryInfo(),
+                traverseSession->getPrevWordPos(), &rootNode);
         traverseSession->getDicTraverseCache()->copyPushActive(&rootNode);
     }
 }
@@ -158,7 +158,7 @@ int Suggest::outputSuggestions(DicTraverseSession *traverseSession, int *frequen
                 terminalIndex, doubleLetterTerminalIndex, doubleLetterLevel);
         const float compoundDistance = terminalDicNode->getCompoundDistance(languageWeight)
                 + doubleLetterCost;
-        const TerminalAttributes terminalAttributes(traverseSession->getOffsetDict(),
+        const TerminalAttributes terminalAttributes(traverseSession->getBinaryDictionaryInfo(),
                 terminalDicNode->getFlags(), terminalDicNode->getAttributesPos());
         const bool isPossiblyOffensiveWord = terminalDicNode->getProbability() <= 0;
         const bool isExactMatch = terminalDicNode->isExactMatch();
@@ -284,7 +284,7 @@ void Suggest::expandCurrentDicNodes(DicTraverseSession *traverseSession) const {
             }
 
             DicNodeUtils::getAllChildDicNodes(
-                    &dicNode, traverseSession->getOffsetDict(), &childDicNodes);
+                    &dicNode, traverseSession->getBinaryDictionaryInfo(), &childDicNodes);
 
             const int childDicNodesSize = childDicNodes.getSizeAndLock();
             for (int i = 0; i < childDicNodesSize; ++i) {
@@ -431,7 +431,8 @@ void Suggest::processDicNodeAsDigraph(DicTraverseSession *traverseSession,
 void Suggest::processDicNodeAsOmission(
         DicTraverseSession *traverseSession, DicNode *dicNode) const {
     DicNodeVector childDicNodes;
-    DicNodeUtils::getAllChildDicNodes(dicNode, traverseSession->getOffsetDict(), &childDicNodes);
+    DicNodeUtils::getAllChildDicNodes(
+            dicNode, traverseSession->getBinaryDictionaryInfo(), &childDicNodes);
 
     const int size = childDicNodes.getSizeAndLock();
     for (int i = 0; i < size; i++) {
@@ -456,7 +457,7 @@ void Suggest::processDicNodeAsInsertion(DicTraverseSession *traverseSession,
         DicNode *dicNode) const {
     const int16_t pointIndex = dicNode->getInputIndex(0);
     DicNodeVector childDicNodes;
-    DicNodeUtils::getProximityChildDicNodes(dicNode, traverseSession->getOffsetDict(),
+    DicNodeUtils::getProximityChildDicNodes(dicNode, traverseSession->getBinaryDictionaryInfo(),
             traverseSession->getProximityInfoState(0), pointIndex + 1, true, &childDicNodes);
     const int size = childDicNodes.getSizeAndLock();
     for (int i = 0; i < size; i++) {
@@ -474,14 +475,14 @@ void Suggest::processDicNodeAsTransposition(DicTraverseSession *traverseSession,
         DicNode *dicNode) const {
     const int16_t pointIndex = dicNode->getInputIndex(0);
     DicNodeVector childDicNodes1;
-    DicNodeUtils::getProximityChildDicNodes(dicNode, traverseSession->getOffsetDict(),
+    DicNodeUtils::getProximityChildDicNodes(dicNode, traverseSession->getBinaryDictionaryInfo(),
             traverseSession->getProximityInfoState(0), pointIndex + 1, false, &childDicNodes1);
     const int childSize1 = childDicNodes1.getSizeAndLock();
     for (int i = 0; i < childSize1; i++) {
         if (childDicNodes1[i]->hasChildren()) {
             DicNodeVector childDicNodes2;
             DicNodeUtils::getProximityChildDicNodes(
-                    childDicNodes1[i], traverseSession->getOffsetDict(),
+                    childDicNodes1[i], traverseSession->getBinaryDictionaryInfo(),
                     traverseSession->getProximityInfoState(0), pointIndex, false, &childDicNodes2);
             const int childSize2 = childDicNodes2.getSizeAndLock();
             for (int j = 0; j < childSize2; j++) {
@@ -521,8 +522,8 @@ void Suggest::createNextWordDicNode(DicTraverseSession *traverseSession, DicNode
 
     // Create a non-cached node here.
     DicNode newDicNode;
-    DicNodeUtils::initAsRootWithPreviousWord(traverseSession->getDicRootPos(),
-            traverseSession->getOffsetDict(), dicNode, &newDicNode);
+    DicNodeUtils::initAsRootWithPreviousWord(
+            traverseSession->getBinaryDictionaryInfo(), dicNode, &newDicNode);
     const CorrectionType correctionType = spaceSubstitution ?
             CT_NEW_WORD_SPACE_SUBSTITUTION : CT_NEW_WORD_SPACE_OMITTION;
     Weighting::addCostAndForwardInputIndex(WEIGHTING, correctionType, traverseSession, dicNode,
diff --git a/native/jni/src/suggest/policyimpl/typing/typing_weighting.h b/native/jni/src/suggest/policyimpl/typing/typing_weighting.h
index 9e0c0d2f7..36d496a27 100644
--- a/native/jni/src/suggest/policyimpl/typing/typing_weighting.h
+++ b/native/jni/src/suggest/policyimpl/typing/typing_weighting.h
@@ -146,7 +146,7 @@ class TypingWeighting : public Weighting {
     float getNewWordBigramCost(const DicTraverseSession *const traverseSession,
             const DicNode *const dicNode,
             MultiBigramMap *const multiBigramMap) const {
-        return DicNodeUtils::getBigramNodeImprobability(traverseSession->getOffsetDict(),
+        return DicNodeUtils::getBigramNodeImprobability(traverseSession->getBinaryDictionaryInfo(),
                 dicNode, multiBigramMap) * ScoringParams::DISTANCE_WEIGHT_LANGUAGE;
     }
 
diff --git a/native/jni/src/unigram_dictionary.cpp b/native/jni/src/unigram_dictionary.cpp
index 1d979dec0..8fd015c62 100644
--- a/native/jni/src/unigram_dictionary.cpp
+++ b/native/jni/src/unigram_dictionary.cpp
@@ -19,6 +19,7 @@
 #define LOG_TAG "LatinIME: unigram_dictionary.cpp"
 
 #include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 #include "suggest/core/dictionary/char_utils.h"
 #include "suggest/core/dictionary/dictionary.h"
@@ -33,8 +34,9 @@
 namespace latinime {
 
 // TODO: check the header
-UnigramDictionary::UnigramDictionary(const uint8_t *const streamStart, const unsigned int dictFlags)
-        : DICT_ROOT(streamStart), ROOT_POS(0),
+UnigramDictionary::UnigramDictionary(
+        const BinaryDictionaryInfo *const binaryDicitonaryInfo, const uint8_t dictFlags)
+        : mBinaryDicitonaryInfo(binaryDicitonaryInfo),
           MAX_DIGRAPH_SEARCH_DEPTH(DEFAULT_MAX_DIGRAPH_SEARCH_DEPTH), DICT_FLAGS(dictFlags) {
     if (DEBUG_DICT) {
         AKLOGI("UnigramDictionary - constructor");
@@ -316,9 +318,10 @@ void UnigramDictionary::getSuggestionCandidates(const bool useFullEditDistance,
     correction->setCorrectionParams(0, 0, 0,
             -1 /* spaceProximityPos */, -1 /* missingSpacePos */, useFullEditDistance,
             doAutoCompletion, maxErrors);
-    int rootPosition = ROOT_POS;
+    int rootPosition = mBinaryDicitonaryInfo->getRootPosition();
     // Get the number of children of root, then increment the position
-    int childCount = BinaryFormat::getGroupCountAndForwardPointer(DICT_ROOT, &rootPosition);
+    int childCount = BinaryFormat::getGroupCountAndForwardPointer(
+            mBinaryDicitonaryInfo->getDictRoot(), &rootPosition);
     int outputIndex = 0;
 
     correction->initCorrectionState(rootPosition, childCount, (inputSize <= 0));
@@ -748,7 +751,7 @@ int UnigramDictionary::getMostProbableWordLikeInner(const int *const inWord, con
     int newWord[MAX_WORD_LENGTH];
     int depth = 0;
     int maxFreq = -1;
-    const uint8_t *const root = DICT_ROOT;
+    const uint8_t *const root = mBinaryDicitonaryInfo->getDictRoot();
     int stackChildCount[MAX_WORD_LENGTH];
     int stackInputIndex[MAX_WORD_LENGTH];
     int stackSiblingPos[MAX_WORD_LENGTH];
@@ -807,7 +810,7 @@ int UnigramDictionary::getMostProbableWordLikeInner(const int *const inWord, con
 }
 
 int UnigramDictionary::getProbability(const int *const inWord, const int length) const {
-    const uint8_t *const root = DICT_ROOT;
+    const uint8_t *const root = mBinaryDicitonaryInfo->getDictRoot();
     int pos = BinaryFormat::getTerminalPosition(root, inWord, length,
             false /* forceLowerCaseSearch */);
     if (NOT_VALID_WORD == pos) {
@@ -824,7 +827,7 @@ int UnigramDictionary::getProbability(const int *const inWord, const int length)
     if (hasMultipleChars) {
         pos = BinaryFormat::skipOtherCharacters(root, pos);
     } else {
-        BinaryFormat::getCodePointAndForwardPointer(DICT_ROOT, &pos);
+        BinaryFormat::getCodePointAndForwardPointer(root, &pos);
     }
     const int unigramProbability = BinaryFormat::readProbabilityWithoutMovingPointer(root, pos);
     return unigramProbability;
@@ -866,7 +869,8 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
     // - FLAG_HAS_MULTIPLE_CHARS: whether this node has multiple char or not.
     // - FLAG_IS_TERMINAL: whether this node is a terminal or not (it may still have children)
     // - FLAG_HAS_BIGRAMS: whether this node has bigrams or not
-    const uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(DICT_ROOT, &pos);
+    const uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(
+            mBinaryDicitonaryInfo->getDictRoot(), &pos);
     const bool hasMultipleChars = (0 != (BinaryFormat::FLAG_HAS_MULTIPLE_CHARS & flags));
     const bool isTerminalNode = (0 != (BinaryFormat::FLAG_IS_TERMINAL & flags));
 
@@ -877,7 +881,8 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
     // else if FLAG_IS_TERMINAL: the probability
     // else if MASK_GROUP_ADDRESS_TYPE is not NONE: the children address
     // Note that you can't have a node that both is not a terminal and has no children.
-    int c = BinaryFormat::getCodePointAndForwardPointer(DICT_ROOT, &pos);
+    int c = BinaryFormat::getCodePointAndForwardPointer(
+            mBinaryDicitonaryInfo->getDictRoot(), &pos);
     ASSERT(NOT_A_CODE_POINT != c);
 
     // We are going to loop through each character and make it look like it's a different
@@ -891,8 +896,8 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
         // We prefetch the next char. If 'c' is the last char of this node, we will have
         // NOT_A_CODE_POINT in the next char. From this we can decide whether this virtual node
         // should behave as a terminal or not and whether we have children.
-        const int nextc = hasMultipleChars
-                ? BinaryFormat::getCodePointAndForwardPointer(DICT_ROOT, &pos) : NOT_A_CODE_POINT;
+        const int nextc = hasMultipleChars ? BinaryFormat::getCodePointAndForwardPointer(
+                    mBinaryDicitonaryInfo->getDictRoot(), &pos) : NOT_A_CODE_POINT;
         const bool isLastChar = (NOT_A_CODE_POINT == nextc);
         // If there are more chars in this nodes, then this virtual node is not a terminal.
         // If we are on the last char, this virtual node is a terminal if this node is.
@@ -912,11 +917,11 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
             // We don't have to output other values because we return false, as in
             // "don't traverse children".
             if (!isLastChar) {
-                pos = BinaryFormat::skipOtherCharacters(DICT_ROOT, pos);
+                pos = BinaryFormat::skipOtherCharacters(mBinaryDicitonaryInfo->getDictRoot(), pos);
             }
             pos = BinaryFormat::skipProbability(flags, pos);
-            *nextSiblingPosition =
-                    BinaryFormat::skipChildrenPosAndAttributes(DICT_ROOT, flags, pos);
+            *nextSiblingPosition = BinaryFormat::skipChildrenPosAndAttributes(
+                    mBinaryDicitonaryInfo->getDictRoot(), flags, pos);
             return false;
         }
 
@@ -929,11 +934,11 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
     if (isTerminalNode) {
         // The probability should be here, because we come here only if this is actually
         // a terminal node, and we are on its last char.
-        const int unigramProbability =
-                BinaryFormat::readProbabilityWithoutMovingPointer(DICT_ROOT, pos);
+        const int unigramProbability = BinaryFormat::readProbabilityWithoutMovingPointer(
+                mBinaryDicitonaryInfo->getDictRoot(), pos);
         const int childrenAddressPos = BinaryFormat::skipProbability(flags, pos);
         const int attributesPos = BinaryFormat::skipChildrenPosition(flags, childrenAddressPos);
-        TerminalAttributes terminalAttributes(DICT_ROOT, flags, attributesPos);
+        TerminalAttributes terminalAttributes(mBinaryDicitonaryInfo, flags, attributesPos);
         // bigramMap contains the bigram frequencies indexed by addresses for fast lookup.
         // bigramFilter is a bloom filter of said frequencies for even faster rejection.
         const int probability = ProbabilityUtils::getProbability(
@@ -953,16 +958,16 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
         // remaining char in this group for there can't be any.
         if (!hasChildren) {
             pos = BinaryFormat::skipProbability(flags, pos);
-            *nextSiblingPosition =
-                    BinaryFormat::skipChildrenPosAndAttributes(DICT_ROOT, flags, pos);
+            *nextSiblingPosition = BinaryFormat::skipChildrenPosAndAttributes(
+                    mBinaryDicitonaryInfo->getDictRoot(), flags, pos);
             return false;
         }
 
         // Optimization: Prune out words that are too long compared to how much was typed.
         if (correction->needsToPrune()) {
             pos = BinaryFormat::skipProbability(flags, pos);
-            *nextSiblingPosition =
-                    BinaryFormat::skipChildrenPosAndAttributes(DICT_ROOT, flags, pos);
+            *nextSiblingPosition = BinaryFormat::skipChildrenPosAndAttributes(
+                    mBinaryDicitonaryInfo->getDictRoot(), flags, pos);
             if (DEBUG_DICT_FULL) {
                 AKLOGI("Traversing was pruned.");
             }
@@ -981,9 +986,12 @@ bool UnigramDictionary::processCurrentNode(const int initialPos,
     // Once this is read, we still need to output the number of nodes in the immediate children of
     // this node, so we read and output it before returning true, as in "please traverse children".
     pos = BinaryFormat::skipProbability(flags, pos);
-    int childrenPos = BinaryFormat::readChildrenPosition(DICT_ROOT, flags, pos);
-    *nextSiblingPosition = BinaryFormat::skipChildrenPosAndAttributes(DICT_ROOT, flags, pos);
-    *newCount = BinaryFormat::getGroupCountAndForwardPointer(DICT_ROOT, &childrenPos);
+    int childrenPos = BinaryFormat::readChildrenPosition(
+            mBinaryDicitonaryInfo->getDictRoot(), flags, pos);
+    *nextSiblingPosition = BinaryFormat::skipChildrenPosAndAttributes(
+            mBinaryDicitonaryInfo->getDictRoot(), flags, pos);
+    *newCount = BinaryFormat::getGroupCountAndForwardPointer(
+            mBinaryDicitonaryInfo->getDictRoot(), &childrenPos);
     *newChildrenPosition = childrenPos;
     return true;
 }
diff --git a/native/jni/src/unigram_dictionary.h b/native/jni/src/unigram_dictionary.h
index a50503256..4edd1f847 100644
--- a/native/jni/src/unigram_dictionary.h
+++ b/native/jni/src/unigram_dictionary.h
@@ -25,6 +25,7 @@
 
 namespace latinime {
 
+class BinaryDictionaryInfo;
 class Correction;
 class ProximityInfo;
 class TerminalAttributes;
@@ -39,7 +40,10 @@ class UnigramDictionary {
     static const int FLAG_MULTIPLE_SUGGEST_ABORT = 0;
     static const int FLAG_MULTIPLE_SUGGEST_SKIP = 1;
     static const int FLAG_MULTIPLE_SUGGEST_CONTINUE = 2;
-    UnigramDictionary(const uint8_t *const streamStart, const unsigned int dictFlags);
+
+    UnigramDictionary(const BinaryDictionaryInfo *const binaryDicitonaryInfo,
+            const uint8_t dictFlags);
+    virtual ~UnigramDictionary();
     int getProbability(const int *const inWord, const int length) const;
     int getBigramPosition(int pos, int *word, int offset, int length) const;
     int getSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
@@ -48,7 +52,6 @@ class UnigramDictionary {
             const bool useFullEditDistance, int *outWords, int *frequencies,
             int *outputTypes) const;
     int getDictFlags() const { return DICT_FLAGS; }
-    virtual ~UnigramDictionary();
 
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(UnigramDictionary);
@@ -108,8 +111,7 @@ class UnigramDictionary {
             const int outputWordLength, int *freqArray, int *wordLengthArray,
             int *outputWord) const;
 
-    const uint8_t *const DICT_ROOT;
-    const int ROOT_POS;
+    const BinaryDictionaryInfo *const mBinaryDicitonaryInfo;
     const int MAX_DIGRAPH_SEARCH_DEPTH;
     const int DICT_FLAGS;
 };