speech-recognition - sphinx4 中的语音识别响应很差

Question

目前我们正在研究使用 sphinx4 进行语音识别。我们正在努力为听写类型的应用程序获得良好的响应。输入是一个 wav 文件，我们希望转录它。我查看了 Sphinx4 提供的 LatticeDemo 和 Transcriber 演示。当我使用相同的配置时，响应很差。我试图调整配置文件，但它根本无法识别这些词。提供的转录器演示是针对数字的，我修改了配置文件以理解单词。但我不确定我是否遗漏了什么。我附上了配置文件。请提出可以进行的任何改进。

<config>        
    <!-- ******************************************************** -->
    <!-- frequently tuned properties                              -->
    <!-- ******************************************************** --> 
    <property name="absoluteBeamWidth"  value="500"/>
    <property name="relativeBeamWidth"  value="1E-60"/>
    <property name="absoluteWordBeamWidth" value="20"/>
    <property name="relativeWordBeamWidth" value="1E-40"/>
    <property name="wordInsertionProbability" value="1E-16"/>
    <property name="languageWeight" value="7.0"/>
    <property name="silenceInsertionProbability" value=".1"/>
    <property name="frontend" value="epFrontEnd"/>
    <property name="recognizer" value="recognizer"/>
    <property name="showCreations" value="false"/>


    <!-- ******************************************************** -->
    <!-- word recognizer configuration                            -->
    <!-- ******************************************************** --> 

    <component name="recognizer" 
                          type="edu.cmu.sphinx.recognizer.Recognizer">
        <property name="decoder" value="decoder"/>
        <propertylist name="monitors">
            <item>accuracyTracker </item>
            <item>speedTracker </item>
            <item>memoryTracker </item>
            <item>recognizerMonitor </item>
        </propertylist>
    </component>

    <!-- ******************************************************** -->
    <!-- The Decoder   configuration                              -->
    <!-- ******************************************************** --> 

    <component name="decoder" type="edu.cmu.sphinx.decoder.Decoder">
        <property name="searchManager" value="wordPruningSearchManager"/>
        <property name="featureBlockSize" value="50"/>
    </component>

    <!-- ******************************************************** -->
    <!-- The Search Manager                                       -->
    <!-- ******************************************************** --> 

    <component name="wordPruningSearchManager" 
    type="edu.cmu.sphinx.decoder.search.WordPruningBreadthFirstSearchManager">
        <property name="logMath" value="logMath"/>
        <property name="linguist" value="lexTreeLinguist"/>
        <property name="pruner" value="trivialPruner"/>
        <property name="scorer" value="threadedScorer"/>
        <property name="activeListManager" value="activeListManager"/>
        <property name="growSkipInterval" value="0"/>
        <property name="checkStateOrder" value="false"/>
        <property name="buildWordLattice" value="true"/>
        <property name="acousticLookaheadFrames" value="1.7"/>
        <property name="relativeBeamWidth" value="${relativeBeamWidth}"/>
    </component>


    <!-- ******************************************************** -->
    <!-- The Active Lists                                         -->
    <!-- ******************************************************** --> 

    <component name="activeListManager" 
             type="edu.cmu.sphinx.decoder.search.SimpleActiveListManager">
        <propertylist name="activeListFactories">
        <item>standardActiveListFactory</item>
        <item>wordActiveListFactory</item>
        <item>wordActiveListFactory</item>
        <item>standardActiveListFactory</item>
        <item>standardActiveListFactory</item>
        <item>standardActiveListFactory</item>
    </propertylist>
    </component>

    <component name="standardActiveListFactory" 
             type="edu.cmu.sphinx.decoder.search.PartitionActiveListFactory">
        <property name="logMath" value="logMath"/>
        <property name="absoluteBeamWidth" value="${absoluteBeamWidth}"/>
        <property name="relativeBeamWidth" value="${relativeBeamWidth}"/>
    </component>

    <component name="wordActiveListFactory" 
             type="edu.cmu.sphinx.decoder.search.PartitionActiveListFactory">
        <property name="logMath" value="logMath"/>
        <property name="absoluteBeamWidth" value="${absoluteWordBeamWidth}"/>
        <property name="relativeBeamWidth" value="${relativeWordBeamWidth}"/>
    </component>

    <!-- ******************************************************** -->
    <!-- The Pruner                                               -->
    <!-- ******************************************************** --> 
    <component name="trivialPruner" 
                type="edu.cmu.sphinx.decoder.pruner.SimplePruner"/>

    <!-- ******************************************************** -->
    <!-- TheScorer                                                -->
    <!-- ******************************************************** --> 
    <component name="threadedScorer" 
                type="edu.cmu.sphinx.decoder.scorer.ThreadedAcousticScorer">
        <property name="frontend" value="${frontend}"/>
    </component>

    <!-- ******************************************************** -->
    <!-- The linguist  configuration                              -->
    <!-- ******************************************************** -->

    <component name="lexTreeLinguist" 
                type="edu.cmu.sphinx.linguist.lextree.LexTreeLinguist">
        <property name="logMath" value="logMath"/>
        <property name="acousticModel" value="wsj"/>
        <property name="languageModel" value="trigramModel"/>
        <property name="dictionary" value="dictionary"/>
        <property name="addFillerWords" value="false"/>
        <property name="fillerInsertionProbability" value="1E-10"/>
        <property name="generateUnitStates" value="false"/>
        <property name="wantUnigramSmear" value="true"/>
        <property name="unigramSmearWeight" value="1"/>
        <property name="wordInsertionProbability" 
                value="${wordInsertionProbability}"/>
        <property name="silenceInsertionProbability" 
                value="${silenceInsertionProbability}"/>
        <property name="languageWeight" value="${languageWeight}"/>
        <property name="unitManager" value="unitManager"/>
    </component>    


    <!-- ******************************************************** -->
    <!-- The Dictionary configuration                            -->
    <!-- ******************************************************** -->
    <component name="dictionary" 
        type="edu.cmu.sphinx.linguist.dictionary.FastDictionary">
        <property name="dictionaryPath"
                  value="resource:/WSJ_8gau_13dCep_16k_40mel_130Hz_6800Hz/dict/cmudict.0.6d"/>
        <property name="fillerPath" 
              value="resource:/WSJ_8gau_13dCep_16k_40mel_130Hz_6800Hz/noisedict"/>
        <property name="addSilEndingPronunciation" value="false"/>
        <property name="wordReplacement" value="&lt;sil&gt;"/>
        <property name="unitManager" value="unitManager"/>
    </component>


    <!-- ******************************************************** -->
    <!-- The Language Model configuration                         -->
    <!-- ******************************************************** -->
    <component name="trigramModel" 
          type="edu.cmu.sphinx.linguist.language.ngram.large.LargeTrigramModel">
        <property name="unigramWeight" value=".5"/>
        <property name="maxDepth" value="3"/>
        <property name="logMath" value="logMath"/>
        <property name="dictionary" value="dictionary"/>
        <property name="location"
         value="./models/language/wsj/wsj5kc.Z.DMP"/>
    </component>


    <!-- ******************************************************** -->
    <!-- The acoustic model configuration                         -->
    <!-- ******************************************************** -->
    <component name="wsj"
               type="edu.cmu.sphinx.linguist.acoustic.tiedstate.TiedStateAcousticModel">
        <property name="loader" value="wsjLoader"/>
        <property name="unitManager" value="unitManager"/>
    </component>

    <component name="wsjLoader" type="edu.cmu.sphinx.linguist.acoustic.tiedstate.Sphinx3Loader">
        <property name="logMath" value="logMath"/>
        <property name="unitManager" value="unitManager"/>
        <property name="location" value="resource:/WSJ_8gau_13dCep_16k_40mel_130Hz_6800Hz"/>
    </component>

    <!-- ******************************************************** -->
    <!-- The unit manager configuration                           -->
    <!-- ******************************************************** -->

    <component name="unitManager" 
        type="edu.cmu.sphinx.linguist.acoustic.UnitManager"/>


    <!-- ******************************************************** -->
    <!-- The frontend configuration                               -->
    <!-- ******************************************************** -->

    <component name="epFrontEnd" type="edu.cmu.sphinx.frontend.FrontEnd">
        <propertylist name="pipeline">
            <item>audioFileDataSource </item>
            <item>dataBlocker </item>
            <item>speechClassifier </item>
            <item>speechMarker </item>
            <item>nonSpeechDataFilter </item>
            <item>preemphasizer </item>
            <item>windower </item>
            <item>fft </item>
            <item>melFilterBank </item>
            <item>dct </item>
            <item>liveCMN </item>
            <item>featureExtraction </item>
        </propertylist>
    </component>

    <component name="audioFileDataSource" type="edu.cmu.sphinx.frontend.util.AudioFileDataSource"/>


    <component name="microphone" 
                type="edu.cmu.sphinx.frontend.util.Microphone">
        <property name="closeBetweenUtterances" value="false"/>
    </component>

    <component name="dataBlocker" type="edu.cmu.sphinx.frontend.DataBlocker"/>

    <component name="speechClassifier"
                type="edu.cmu.sphinx.frontend.endpoint.SpeechClassifier">
        <property name="threshold" value="13"/>
    </component>

    <component name="nonSpeechDataFilter" 
                type="edu.cmu.sphinx.frontend.endpoint.NonSpeechDataFilter"/>

    <component name="speechMarker" 
                type="edu.cmu.sphinx.frontend.endpoint.SpeechMarker">
        <property name="speechTrailer" value="50"/>
    </component>

    <component name="preemphasizer"
        type="edu.cmu.sphinx.frontend.filter.Preemphasizer"/>

    <component name="windower" 
    type="edu.cmu.sphinx.frontend.window.RaisedCosineWindower"/>

    <component name="fft" 
        type="edu.cmu.sphinx.frontend.transform.DiscreteFourierTransform"/>

    <component name="melFilterBank" 
        type="edu.cmu.sphinx.frontend.frequencywarp.MelFrequencyFilterBank"/>

    <component name="dct" 
            type="edu.cmu.sphinx.frontend.transform.DiscreteCosineTransform"/>

    <component name="liveCMN" 
                type="edu.cmu.sphinx.frontend.feature.LiveCMN"/>

    <component name="featureExtraction" 
        type="edu.cmu.sphinx.frontend.feature.DeltasFeatureExtractor"/>

    <!-- Newly Added..   -->
    <component name="streamDataSource"
        type="edu.cmu.sphinx.frontend.util.StreamDataSource">
        <property name="sampleRate" value="16000"/>
        <property name="bigEndianData" value="false"/>
    </component>

    <!-- ******************************************************* -->
    <!--  monitors                                               -->
    <!-- ******************************************************* -->

    <component name="accuracyTracker" 
                type="edu.cmu.sphinx.instrumentation.BestPathAccuracyTracker">
        <property name="recognizer" value="${recognizer}"/>
        <property name="showRawResults" value="false"/>
        <property name="showAlignedResults" value="false"/>
    </component>

    <component name="memoryTracker" 
                type="edu.cmu.sphinx.instrumentation.MemoryTracker">
        <property name="recognizer" value="${recognizer}"/>
    <property name="showDetails" value="false"/>
    <property name="showSummary" value="false"/>
    </component>

    <component name="speedTracker" 
                type="edu.cmu.sphinx.instrumentation.SpeedTracker">
        <property name="recognizer" value="${recognizer}"/>
        <property name="frontend" value="${frontend}"/>
    <property name="showDetails" value="false"/>
    </component>

    <component name="recognizerMonitor" 
                type="edu.cmu.sphinx.instrumentation.RecognizerMonitor">
        <property name="recognizer" value="${recognizer}"/>
        <propertylist name="allocatedMonitors">
            <item>configMonitor </item>
        </propertylist>
    </component>

    <component name="configMonitor" 
                type="edu.cmu.sphinx.instrumentation.ConfigMonitor">
        <property name="showConfig" value="false"/>
    </component>


    <!-- ******************************************************* -->
    <!--  Miscellaneous components                               -->
    <!-- ******************************************************* -->

    <component name="logMath" type="edu.cmu.sphinx.util.LogMath">
        <property name="logBase" value="1.0001"/>
        <property name="useAddTable" value="true"/>
    </component>
</config>

Answer 1

识别准确度不佳的最常见原因是:

1. 传入音频的采样率不匹配。它必须是 16khz 16bit mono little-endian 文件。您需要通过重采样来固定源的采样率。

2. 从 mp3 解码的音频文件中的零静音区域会破坏解码器。可以使用抖动引入小的随机噪声来解决这个问题。

3. 声学模型不匹配。您可以使用声学模型自适应来提高准确性

4. 语言模型不匹配。您可以创建自己的语言模型来匹配您尝试解码的词汇。

您可以从教程中获得更多信息:

http://cmusphinx.sourceforge.net/wiki/tutorial

要获得更详细的帮助，您可以随时提供您尝试解码的音频样本。他们将帮助开发人员更好地分析问题。提供您从解码器获得的实际结果和您的期望也很有帮助。