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Diffstat (limited to 'native/src/correction.cpp')
| -rw-r--r-- | native/src/correction.cpp | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/native/src/correction.cpp b/native/src/correction.cpp new file mode 100644 index 000000000..6d682c0c9 --- /dev/null +++ b/native/src/correction.cpp @@ -0,0 +1,443 @@ +/* + * Copyright (C) 2011 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 <assert.h> +#include <stdio.h> +#include <string.h> + +#define LOG_TAG "LatinIME: correction.cpp" + +#include "correction.h" +#include "proximity_info.h" + +namespace latinime { + +////////////////////// +// inline functions // +////////////////////// +static const char QUOTE = '\''; + +inline bool Correction::isQuote(const unsigned short c) { + const unsigned short userTypedChar = mProximityInfo->getPrimaryCharAt(mInputIndex); + return (c == QUOTE && userTypedChar != QUOTE); +} + +//////////////// +// Correction // +//////////////// + +Correction::Correction(const int typedLetterMultiplier, const int fullWordMultiplier) + : TYPED_LETTER_MULTIPLIER(typedLetterMultiplier), FULL_WORD_MULTIPLIER(fullWordMultiplier) { +} + +void Correction::initCorrection(const ProximityInfo *pi, const int inputLength, + const int maxDepth) { + mProximityInfo = pi; + mInputLength = inputLength; + mMaxDepth = maxDepth; + mMaxEditDistance = mInputLength < 5 ? 2 : mInputLength / 2; + mSkippedOutputIndex = -1; +} + +void Correction::setCorrectionParams(const int skipPos, const int excessivePos, + const int transposedPos, const int spaceProximityPos, const int missingSpacePos) { + mSkipPos = skipPos; + mExcessivePos = excessivePos; + mTransposedPos = transposedPos; + mSpaceProximityPos = spaceProximityPos; + mMissingSpacePos = missingSpacePos; +} + +void Correction::checkState() { + if (DEBUG_DICT) { + int inputCount = 0; + if (mSkipPos >= 0) ++inputCount; + if (mExcessivePos >= 0) ++inputCount; + if (mTransposedPos >= 0) ++inputCount; + // TODO: remove this assert + assert(inputCount <= 1); + } +} + +int Correction::getFreqForSplitTwoWords(const int firstFreq, const int secondFreq) { + return Correction::RankingAlgorithm::calcFreqForSplitTwoWords(firstFreq, secondFreq, this); +} + +int Correction::getFinalFreq(const int freq, unsigned short **word, int *wordLength) { + const int outputIndex = mTerminalOutputIndex; + const int inputIndex = mTerminalInputIndex; + *wordLength = outputIndex + 1; + if (mProximityInfo->sameAsTyped(mWord, outputIndex + 1) || outputIndex < MIN_SUGGEST_DEPTH) { + return -1; + } + *word = mWord; + const bool sameLength = (mExcessivePos == mInputLength - 1) ? (mInputLength == inputIndex + 2) + : (mInputLength == inputIndex + 1); + return Correction::RankingAlgorithm::calculateFinalFreq( + inputIndex, outputIndex, mMatchedCharCount, freq, sameLength, this); +} + +void Correction::initProcessState(const int matchCount, const int inputIndex, + const int outputIndex, const bool traverseAllNodes, const int diffs) { + mMatchedCharCount = matchCount; + mInputIndex = inputIndex; + mOutputIndex = outputIndex; + mTraverseAllNodes = traverseAllNodes; + mDiffs = diffs; +} + +void Correction::getProcessState(int *matchedCount, int *inputIndex, int *outputIndex, + bool *traverseAllNodes, int *diffs) { + *matchedCount = mMatchedCharCount; + *inputIndex = mInputIndex; + *outputIndex = mOutputIndex; + *traverseAllNodes = mTraverseAllNodes; + *diffs = mDiffs; +} + +void Correction::charMatched() { + ++mMatchedCharCount; +} + +// TODO: remove +int Correction::getOutputIndex() { + return mOutputIndex; +} + +// TODO: remove +int Correction::getInputIndex() { + return mInputIndex; +} + +// TODO: remove +bool Correction::needsToTraverseAll() { + return mTraverseAllNodes; +} + +void Correction::incrementInputIndex() { + ++mInputIndex; +} + +void Correction::incrementOutputIndex() { + ++mOutputIndex; +} + +void Correction::startTraverseAll() { + mTraverseAllNodes = true; +} + +bool Correction::needsToPrune() const { + return (mOutputIndex - 1 >= (mTransposedPos >= 0 ? mInputLength - 1 : mMaxDepth) + || mDiffs > mMaxEditDistance); +} + +Correction::CorrectionType Correction::processSkipChar( + const int32_t c, const bool isTerminal) { + mWord[mOutputIndex] = c; + if (needsToTraverseAll() && isTerminal) { + mTerminalInputIndex = mInputIndex; + mTerminalOutputIndex = mOutputIndex; + incrementOutputIndex(); + return TRAVERSE_ALL_ON_TERMINAL; + } else { + incrementOutputIndex(); + return TRAVERSE_ALL_NOT_ON_TERMINAL; + } +} + +Correction::CorrectionType Correction::processCharAndCalcState( + const int32_t c, const bool isTerminal) { + CorrectionType currentStateType = NOT_ON_TERMINAL; + // This has to be done for each virtual char (this forwards the "inputIndex" which + // is the index in the user-inputted chars, as read by proximity chars. + if (mExcessivePos == mOutputIndex && mInputIndex < mInputLength - 1) { + incrementInputIndex(); + } + + bool skip = false; + if (mSkipPos >= 0) { + skip = mSkipPos == mOutputIndex; + } + + if (mTraverseAllNodes || isQuote(c)) { + return processSkipChar(c, isTerminal); + } else { + int inputIndexForProximity = mInputIndex; + + if (mTransposedPos >= 0) { + if (mInputIndex == mTransposedPos) { + ++inputIndexForProximity; + } + if (mInputIndex == (mTransposedPos + 1)) { + --inputIndexForProximity; + } + } + + const bool checkProximityChars = + !(mSkipPos >= 0 || mExcessivePos >= 0 || mTransposedPos >= 0); + int matchedProximityCharId = mProximityInfo->getMatchedProximityId( + inputIndexForProximity, c, checkProximityChars); + + const bool unrelated = ProximityInfo::UNRELATED_CHAR == matchedProximityCharId; + if (unrelated) { + if (skip) { + // Skip this letter and continue deeper + mSkippedOutputIndex = mOutputIndex; + return processSkipChar(c, isTerminal); + } else { + return UNRELATED; + } + } + + // No need to skip. Finish traversing and increment skipPos. + // TODO: Remove this? + if (skip) { + mWord[mOutputIndex] = c; + incrementOutputIndex(); + return TRAVERSE_ALL_NOT_ON_TERMINAL; + } + + mWord[mOutputIndex] = c; + // If inputIndex is greater than mInputLength, that means there is no + // proximity chars. So, we don't need to check proximity. + if (ProximityInfo::SAME_OR_ACCENTED_OR_CAPITALIZED_CHAR == matchedProximityCharId) { + charMatched(); + } + + if (ProximityInfo::NEAR_PROXIMITY_CHAR == matchedProximityCharId) { + incrementDiffs(); + } + + const bool isSameAsUserTypedLength = mInputLength + == getInputIndex() + 1 + || (mExcessivePos == mInputLength - 1 + && getInputIndex() == mInputLength - 2); + if (isSameAsUserTypedLength && isTerminal) { + mTerminalInputIndex = mInputIndex; + mTerminalOutputIndex = mOutputIndex; + currentStateType = ON_TERMINAL; + } + // Start traversing all nodes after the index exceeds the user typed length + if (isSameAsUserTypedLength) { + startTraverseAll(); + } + + // Finally, we are ready to go to the next character, the next "virtual node". + // We should advance the input index. + // We do this in this branch of the 'if traverseAllNodes' because we are still matching + // characters to input; the other branch is not matching them but searching for + // completions, this is why it does not have to do it. + incrementInputIndex(); + } + + // Also, the next char is one "virtual node" depth more than this char. + incrementOutputIndex(); + + return currentStateType; +} + +Correction::~Correction() { +} + +///////////////////////// +// static inline utils // +///////////////////////// + +static const int TWO_31ST_DIV_255 = S_INT_MAX / 255; +static inline int capped255MultForFullMatchAccentsOrCapitalizationDifference(const int num) { + return (num < TWO_31ST_DIV_255 ? 255 * num : S_INT_MAX); +} + +static const int TWO_31ST_DIV_2 = S_INT_MAX / 2; +inline static void multiplyIntCapped(const int multiplier, int *base) { + const int temp = *base; + if (temp != S_INT_MAX) { + // Branch if multiplier == 2 for the optimization + if (multiplier == 2) { + *base = TWO_31ST_DIV_2 >= temp ? temp << 1 : S_INT_MAX; + } else { + const int tempRetval = temp * multiplier; + *base = tempRetval >= temp ? tempRetval : S_INT_MAX; + } + } +} + +inline static int powerIntCapped(const int base, const int n) { + if (n == 0) return 1; + if (base == 2) { + return n < 31 ? 1 << n : S_INT_MAX; + } else { + int ret = base; + for (int i = 1; i < n; ++i) multiplyIntCapped(base, &ret); + return ret; + } +} + +inline static void multiplyRate(const int rate, int *freq) { + if (*freq != S_INT_MAX) { + if (*freq > 1000000) { + *freq /= 100; + multiplyIntCapped(rate, freq); + } else { + multiplyIntCapped(rate, freq); + *freq /= 100; + } + } +} + +////////////////////// +// RankingAlgorithm // +////////////////////// + +int Correction::RankingAlgorithm::calculateFinalFreq( + const int inputIndex, const int outputIndex, + const int matchCount, const int freq, const bool sameLength, + const Correction* correction) { + const int skipPos = correction->getSkipPos(); + const int excessivePos = correction->getExcessivePos(); + const int transposedPos = correction->getTransposedPos(); + const int inputLength = correction->mInputLength; + const int typedLetterMultiplier = correction->TYPED_LETTER_MULTIPLIER; + const int fullWordMultiplier = correction->FULL_WORD_MULTIPLIER; + const ProximityInfo *proximityInfo = correction->mProximityInfo; + const int matchWeight = powerIntCapped(typedLetterMultiplier, matchCount); + + // TODO: Demote by edit distance + int finalFreq = freq * matchWeight; + if (skipPos >= 0) { + if (inputLength >= 2) { + const int demotionRate = WORDS_WITH_MISSING_CHARACTER_DEMOTION_RATE + * (10 * inputLength - WORDS_WITH_MISSING_CHARACTER_DEMOTION_START_POS_10X) + / (10 * inputLength + - WORDS_WITH_MISSING_CHARACTER_DEMOTION_START_POS_10X + 10); + if (DEBUG_DICT_FULL) { + LOGI("Demotion rate for missing character is %d.", demotionRate); + } + multiplyRate(demotionRate, &finalFreq); + } else { + finalFreq = 0; + } + } + if (transposedPos >= 0) multiplyRate( + WORDS_WITH_TRANSPOSED_CHARACTERS_DEMOTION_RATE, &finalFreq); + if (excessivePos >= 0) { + multiplyRate(WORDS_WITH_EXCESSIVE_CHARACTER_DEMOTION_RATE, &finalFreq); + if (!proximityInfo->existsAdjacentProximityChars(inputIndex)) { + // If an excessive character is not adjacent to the left char or the right char, + // we will demote this word. + multiplyRate(WORDS_WITH_EXCESSIVE_CHARACTER_OUT_OF_PROXIMITY_DEMOTION_RATE, &finalFreq); + } + } + int lengthFreq = typedLetterMultiplier; + multiplyIntCapped(powerIntCapped(typedLetterMultiplier, outputIndex), &lengthFreq); + if ((outputIndex + 1) == matchCount) { + // Full exact match + if (outputIndex > 1) { + if (DEBUG_DICT) { + LOGI("Found full matched word."); + } + multiplyRate(FULL_MATCHED_WORDS_PROMOTION_RATE, &finalFreq); + } + if (sameLength && transposedPos < 0 && skipPos < 0 && excessivePos < 0) { + finalFreq = capped255MultForFullMatchAccentsOrCapitalizationDifference(finalFreq); + } + } else if (sameLength && transposedPos < 0 && skipPos < 0 && excessivePos < 0 + && outputIndex > 0) { + // A word with proximity corrections + if (DEBUG_DICT) { + LOGI("Found one proximity correction."); + } + multiplyIntCapped(typedLetterMultiplier, &finalFreq); + multiplyRate(WORDS_WITH_PROXIMITY_CHARACTER_DEMOTION_RATE, &finalFreq); + } + if (DEBUG_DICT) { + LOGI("calc: %d, %d", outputIndex, sameLength); + } + if (sameLength) multiplyIntCapped(fullWordMultiplier, &finalFreq); + return finalFreq; +} + +int Correction::RankingAlgorithm::calcFreqForSplitTwoWords( + const int firstFreq, const int secondFreq, const Correction* correction) { + const int spaceProximityPos = correction->mSpaceProximityPos; + const int missingSpacePos = correction->mMissingSpacePos; + if (DEBUG_DICT) { + int inputCount = 0; + if (spaceProximityPos >= 0) ++inputCount; + if (missingSpacePos >= 0) ++inputCount; + assert(inputCount <= 1); + } + const bool isSpaceProximity = spaceProximityPos >= 0; + const int inputLength = correction->mInputLength; + const int firstWordLength = isSpaceProximity ? spaceProximityPos : missingSpacePos; + const int secondWordLength = isSpaceProximity + ? (inputLength - spaceProximityPos - 1) + : (inputLength - missingSpacePos); + const int typedLetterMultiplier = correction->TYPED_LETTER_MULTIPLIER; + + if (firstWordLength == 0 || secondWordLength == 0) { + return 0; + } + const int firstDemotionRate = 100 - 100 / (firstWordLength + 1); + int tempFirstFreq = firstFreq; + multiplyRate(firstDemotionRate, &tempFirstFreq); + + const int secondDemotionRate = 100 - 100 / (secondWordLength + 1); + int tempSecondFreq = secondFreq; + multiplyRate(secondDemotionRate, &tempSecondFreq); + + const int totalLength = firstWordLength + secondWordLength; + + // Promote pairFreq with multiplying by 2, because the word length is the same as the typed + // length. + int totalFreq = tempFirstFreq + tempSecondFreq; + + // This is a workaround to try offsetting the not-enough-demotion which will be done in + // calcNormalizedScore in Utils.java. + // In calcNormalizedScore the score will be demoted by (1 - 1 / length) + // but we demoted only (1 - 1 / (length + 1)) so we will additionally adjust freq by + // (1 - 1 / length) / (1 - 1 / (length + 1)) = (1 - 1 / (length * length)) + const int normalizedScoreNotEnoughDemotionAdjustment = 100 - 100 / (totalLength * totalLength); + multiplyRate(normalizedScoreNotEnoughDemotionAdjustment, &totalFreq); + + // At this moment, totalFreq is calculated by the following formula: + // (firstFreq * (1 - 1 / (firstWordLength + 1)) + secondFreq * (1 - 1 / (secondWordLength + 1))) + // * (1 - 1 / totalLength) / (1 - 1 / (totalLength + 1)) + + multiplyIntCapped(powerIntCapped(typedLetterMultiplier, totalLength), &totalFreq); + + // This is another workaround to offset the demotion which will be done in + // calcNormalizedScore in Utils.java. + // In calcNormalizedScore the score will be demoted by (1 - 1 / length) so we have to promote + // the same amount because we already have adjusted the synthetic freq of this "missing or + // mistyped space" suggestion candidate above in this method. + const int normalizedScoreDemotionRateOffset = (100 + 100 / totalLength); + multiplyRate(normalizedScoreDemotionRateOffset, &totalFreq); + + if (isSpaceProximity) { + // A word pair with one space proximity correction + if (DEBUG_DICT) { + LOGI("Found a word pair with space proximity correction."); + } + multiplyIntCapped(typedLetterMultiplier, &totalFreq); + multiplyRate(WORDS_WITH_PROXIMITY_CHARACTER_DEMOTION_RATE, &totalFreq); + } + + multiplyRate(WORDS_WITH_MISSING_SPACE_CHARACTER_DEMOTION_RATE, &totalFreq); + return totalFreq; +} + +} // namespace latinime |