Support for fbank features added.

README.md

@@ -53,6 +53,7 @@ Example of `alex_asr.conf` that should reside in `model_dir`:
 
 ```
 --model_type=nnet2     # Supported model types are nnet2 (nnet2::AmNnet) and gmm (AmDiagGmm)
+--feature_type=mfcc    # Supported feature types are mfcc and fbank
 --model=final.mdl      # Filename of the mdl file for the decoder.
 --hclg=HCLG.fst        # Filename of the fst file with decoding HCLG fst.
 --words=words.txt      # Filename with a list of words (each line contains: ""<word> <word-id>").
@@ -73,6 +74,7 @@ Example of `alex_asr.conf` that should reside in `model_dir`:
 --cfg_decoder=decoder.cfg
 --cfg_decodable=decodable.cfg
 --cfg_mfcc=mfcc.cfg
+--cfg_fbank=fbank.cfg
 --cfg_cmvn=cmvn.cfg
 --cfg_splice=splice.cfg
 --cfg_endpoint=endpoint.cfg
@@ -112,6 +114,16 @@ Example ``mfcc.cfg``:
 
 Details: https://github.com/kaldi-asr/kaldi/blob/master/src/feat/feature-mfcc.h#L63
 
+## FBANK configuration
+
+Example ``fbank.cfg``:
+```
+--low-freq=128
+--high-freq=3800
+```
+
+Details: https://github.com/kaldi-asr/kaldi/blob/master/src/feat/feature-fbank.h#L62
+
 ## Online CMVN configuration
 
 Online CMVN configuration is needed when you set ``--use_cmvn=true``.

src/decoder.cc

@@ -124,12 +124,12 @@ namespace alex_asr {
 
     bool Decoder::EndpointDetected() {
         return kaldi::EndpointDetected(config_->endpoint_config, *trans_model_,
-                                       config_->mfcc_opts.frame_opts.frame_shift_ms * 1.0e-03f,
+                                       config_->FrameShiftInSeconds(),
                                        *decoder_);
     }
 
     void Decoder::FrameIn(VectorBase<BaseFloat> *waveform_in) {
-        feature_pipeline_->AcceptWaveform(config_->mfcc_opts.frame_opts.samp_freq, *waveform_in);
+        feature_pipeline_->AcceptWaveform(config_->SamplingFrequency(), *waveform_in);
     }
 
     void Decoder::FrameIn(unsigned char *buffer, int32 buffer_length) {

src/decoder_config.cc

@@ -14,6 +14,7 @@ namespace alex_asr {
             cfg_decoder(""),
             cfg_decodable(""),
             cfg_mfcc(""),
+            cfg_fbank(""),
             cfg_cmvn(""),
             cfg_splice(""),
             cfg_endpoint(""),
@@ -33,6 +34,7 @@ namespace alex_asr {
 
     void DecoderConfig::Register(ParseOptions *po) {
         po->Register("model_type", &model_type_str, "Type of model. GMM/NNET2");
+        po->Register("feature_type", &feature_type_str, "Type of features. MFCC/FBANK");
         po->Register("model", &model_rxfilename, "Accoustic model filename.");
         po->Register("hclg", &fst_rxfilename, "HCLG FST filename.");
         po->Register("words", &words_rxfilename, "Word to ID mapping filename.");
@@ -47,6 +49,7 @@ namespace alex_asr {
         po->Register("cfg_decoder", &cfg_decoder, "");
         po->Register("cfg_decodable", &cfg_decodable, "");
         po->Register("cfg_mfcc", &cfg_mfcc, "");
+        po->Register("cfg_fbank", &cfg_fbank, "");
         po->Register("cfg_cmvn", &cfg_cmvn, "");
         po->Register("cfg_splice", &cfg_splice, "");
         po->Register("cfg_endpoint", &cfg_endpoint, "");
@@ -66,6 +69,7 @@ namespace alex_asr {
         LoadConfig(cfg_decoder, &decoder_opts);
         LoadConfig(cfg_decodable, &decodable_opts);
         LoadConfig(cfg_mfcc, &mfcc_opts);
+        LoadConfig(cfg_fbank, &fbank_opts);
         LoadConfig(cfg_cmvn, &cmvn_opts);
         LoadConfig(cfg_splice, &splice_opts);
         LoadConfig(cfg_endpoint, &endpoint_config);
@@ -160,9 +164,17 @@ namespace alex_asr {
             res = false;
 
             KALDI_ERR << "You have to specify a valid model_type.";
-
         }
 
+        if(feature_type_str == "mfcc" || feature_type_str == "") {
+            feature_type = MFCC;
+        } else if(feature_type_str == "fbank") {
+            feature_type = FBANK;
+        } else {
+            res = false;
+
+            KALDI_ERR << "You have to specify a valid feature_type.";
+        }
 
         res &= OptionCheck(use_ivectors && cfg_ivector == "",
                            "You have to specify --cfg_ivector if you want to use ivectors.");
@@ -193,4 +205,26 @@ namespace alex_asr {
         }
         return true;
     }
-}
+
+    BaseFloat DecoderConfig::FrameShiftInSeconds() const {
+        if(feature_type == DecoderConfig::MFCC) {
+            return mfcc_opts.frame_opts.frame_shift_ms * 1.0e-03;
+        } else if(feature_type == DecoderConfig::FBANK) {
+            return fbank_opts.frame_opts.frame_shift_ms * 1.0e-03;
+        } else {
+            KALDI_ERR << "You have to specify a valid feature_type.";
+            return 0.0;
+        }
+    }
+
+    BaseFloat DecoderConfig::SamplingFrequency() const {
+        if(feature_type == DecoderConfig::MFCC) {
+            return mfcc_opts.frame_opts.samp_freq;
+        } else if(feature_type == DecoderConfig::FBANK) {
+            return fbank_opts.frame_opts.samp_freq;
+        } else {
+            KALDI_ERR << "You have to specify a valid feature_type.";
+            return 0.0;
+        }
+    }
+}

src/decoder_config.h

@@ -19,17 +19,21 @@ using namespace kaldi;
 namespace alex_asr {
     class DecoderConfig {
     public:
-        enum ModelType { None, GMM, NNET2 };
+        enum ModelType { NoneModelType, GMM, NNET2 };
+        enum FeatureType { NoneFeatureType, MFCC, FBANK };
 
         DecoderConfig();
         ~DecoderConfig();
         void Register(ParseOptions *po);
         void LoadConfigs(const string cfg_file);
         bool InitAndCheck();
+        BaseFloat FrameShiftInSeconds() const;
+        BaseFloat SamplingFrequency() const;
 
         LatticeFasterDecoderConfig decoder_opts;
         nnet2::DecodableNnet2OnlineOptions decodable_opts;
         MfccOptions mfcc_opts;
+        FbankOptions fbank_opts;
         OnlineCmvnOptions cmvn_opts;
         OnlineSpliceOptions splice_opts;
         OnlineEndpointConfig endpoint_config;
@@ -42,6 +46,7 @@ namespace alex_asr {
         OnlineIvectorExtractionInfo *ivector_extraction_info;
 
         ModelType model_type;
+        FeatureType feature_type;
         int32 bits_per_sample;
 
         bool use_lda;
@@ -53,6 +58,7 @@ namespace alex_asr {
         std::string cfg_decoder;
         std::string cfg_decodable;
         std::string cfg_mfcc;
+        std::string cfg_fbank;
         std::string cfg_cmvn;
         std::string cfg_splice;
         std::string cfg_endpoint;
@@ -74,6 +80,7 @@ namespace alex_asr {
         bool OptionCheck(bool cond, std::string fail_text);
 
         string model_type_str;
+        string feature_type_str;
     };
 }
 

src/feature_pipeline.cc

@@ -1,10 +1,12 @@
+#include "src/decoder_config.h"
+
 #include "feature_pipeline.h"
 
 using namespace kaldi;
 
 namespace alex_asr {
     FeaturePipeline::FeaturePipeline(DecoderConfig &config) :
-        mfcc_(NULL),
+        base_feature_(NULL),
         cmvn_(NULL),
         cmvn_state_(NULL),
         splice_(NULL),
@@ -19,11 +21,21 @@ namespace alex_asr {
     {
         OnlineFeatureInterface *prev_feature;
 
-        KALDI_VLOG(3) << "Feature MFCC "
-                      << config.mfcc_opts.mel_opts.low_freq
-                      << " " << config.mfcc_opts.mel_opts.high_freq;
-        prev_feature = mfcc_ = new OnlineMfcc(config.mfcc_opts);
-        KALDI_VLOG(3) << "    -> dims: " << mfcc_->Dim();
+        if(config.feature_type == DecoderConfig::MFCC) {
+            KALDI_VLOG(3) << "Feature MFCC "
+                          << config.mfcc_opts.mel_opts.low_freq
+                          << " " << config.mfcc_opts.mel_opts.high_freq;
+            prev_feature = base_feature_ = new OnlineMfcc(config.mfcc_opts);
+            KALDI_VLOG(3) << "    -> dims: " << base_feature_->Dim();
+        } else if(config.feature_type == DecoderConfig::FBANK) {
+            KALDI_VLOG(3) << "Feature FBANK "
+                          << config.fbank_opts.mel_opts.low_freq
+                          << " " << config.fbank_opts.mel_opts.high_freq;
+            prev_feature = base_feature_ = new OnlineFbank(config.fbank_opts);
+            KALDI_VLOG(3) << "    -> dims: " << base_feature_->Dim();
+        } else {
+            KALDI_ERR << "You have to specify a valid feature_type.";
+        }
 
         if (config.use_cmvn) {
             KALDI_VLOG(3) << "Feature CMVN";
@@ -50,7 +62,7 @@ namespace alex_asr {
 
         if (config.use_ivectors) {
             KALDI_VLOG(3) << "Feature IVectors";
-            ivector_ = new OnlineIvectorFeature(*config.ivector_extraction_info, mfcc_);
+            ivector_ = new OnlineIvectorFeature(*config.ivector_extraction_info, base_feature_);
             prev_feature = ivector_append_ = new OnlineAppendFeature(prev_feature, ivector_);
             KALDI_VLOG(3) << "     -> dims: " << prev_feature->Dim();
         }
@@ -59,7 +71,7 @@ namespace alex_asr {
     }
 
     FeaturePipeline::~FeaturePipeline() {
-        delete mfcc_;
+        delete base_feature_;
         delete cmvn_;
         delete cmvn_state_;
         delete splice_;
@@ -77,14 +89,14 @@ namespace alex_asr {
 
     void FeaturePipeline::AcceptWaveform(BaseFloat sampling_rate,
                                                  const VectorBase<BaseFloat> &waveform) {
-        mfcc_->AcceptWaveform(sampling_rate, waveform);
+        base_feature_->AcceptWaveform(sampling_rate, waveform);
         if(pitch_) {
             pitch_->AcceptWaveform(sampling_rate, waveform);
         }
     }
 
     void FeaturePipeline::InputFinished() {
-        mfcc_->InputFinished();
+        base_feature_->InputFinished();
         if(pitch_) {
             pitch_->InputFinished();
         }

src/feature_pipeline.h

@@ -16,7 +16,7 @@ namespace alex_asr {
         void InputFinished();
         OnlineIvectorFeature* GetIvectorFeature();
     private:
-        OnlineMfcc *mfcc_;
+        OnlineBaseFeature *base_feature_;
         OnlineCmvn *cmvn_;
         OnlineCmvnState *cmvn_state_;
         OnlineSpliceFrames *splice_;

test/asr_model_digits/alex_asr.conf

@@ -1,4 +1,5 @@
 --model_type=gmm
+--feature_type=mfcc
 --model=final.mdl
 --hclg=HCLG.fst
 --words=words.txt