diff --git a/speechx/examples/ds2_ol/decoder/ctc-prefix-beam-search-decoder-ol.cc b/speechx/examples/ds2_ol/decoder/ctc-prefix-beam-search-decoder-ol.cc
index 46a78ef9..eaec41b7 100644
--- a/speechx/examples/ds2_ol/decoder/ctc-prefix-beam-search-decoder-ol.cc
+++ b/speechx/examples/ds2_ol/decoder/ctc-prefix-beam-search-decoder-ol.cc
@@ -98,6 +98,7 @@ int main(int argc, char* argv[]) {
     LOG(INFO) << "receptive field (frame): " << receptive_field_length;
     decoder.InitDecoder();
 
+    kaldi::Timer timer;
     for (; !feature_reader.Done(); feature_reader.Next()) {
         string utt = feature_reader.Key();
         kaldi::Matrix<BaseFloat> feature = feature_reader.Value();
@@ -160,5 +161,7 @@ int main(int argc, char* argv[]) {
 
     KALDI_LOG << "Done " << num_done << " utterances, " << num_err
               << " with errors.";
+    double elapsed = timer.Elapsed();
+    KALDI_LOG << " cost:" << elapsed << " s";
     return (num_done != 0 ? 0 : 1);
 }
diff --git a/speechx/examples/ds2_ol/decoder/recognizer_test_main.cc b/speechx/examples/ds2_ol/decoder/recognizer_test_main.cc
index e6fed0ed..00764f53 100644
--- a/speechx/examples/ds2_ol/decoder/recognizer_test_main.cc
+++ b/speechx/examples/ds2_ol/decoder/recognizer_test_main.cc
@@ -38,6 +38,9 @@ int main(int argc, char* argv[]) {
     LOG(INFO) << "chunk size (sample): " << chunk_sample_size;
 
     int32 num_done = 0, num_err = 0;
+    double tot_wav_duration = 0.0;
+
+    kaldi::Timer timer;
 
     for (; !wav_reader.Done(); wav_reader.Next()) {
         std::string utt = wav_reader.Key();
@@ -47,6 +50,7 @@ int main(int argc, char* argv[]) {
         kaldi::SubVector<kaldi::BaseFloat> waveform(wave_data.Data(),
                                                     this_channel);
         int tot_samples = waveform.Dim();
+        tot_wav_duration += tot_samples * 1.0 / sample_rate;
         LOG(INFO) << "wav len (sample): " << tot_samples;
 
         int sample_offset = 0;
@@ -85,4 +89,9 @@ int main(int argc, char* argv[]) {
         result_writer.Write(utt, result);
         ++num_done;
     }
+    double elapsed = timer.Elapsed();
+    KALDI_LOG << "Done " << num_done << " out of " << (num_err + num_done);
+    KALDI_LOG << " cost:" << elapsed << " s";
+    KALDI_LOG << "total wav duration is: " << tot_wav_duration << " s";
+    KALDI_LOG << "the RTF is: " << elapsed / tot_wav_duration;
 }
\ No newline at end of file
diff --git a/speechx/examples/ds2_ol/decoder/wfst-decoder-ol.cc b/speechx/examples/ds2_ol/decoder/wfst-decoder-ol.cc
index cb68a5a2..fefc16d2 100644
--- a/speechx/examples/ds2_ol/decoder/wfst-decoder-ol.cc
+++ b/speechx/examples/ds2_ol/decoder/wfst-decoder-ol.cc
@@ -100,7 +100,7 @@ int main(int argc, char* argv[]) {
     LOG(INFO) << "chunk stride (frame): " << chunk_stride;
     LOG(INFO) << "receptive field (frame): " << receptive_field_length;
     decoder.InitDecoder();
-
+    kaldi::Timer timer;
     for (; !feature_reader.Done(); feature_reader.Next()) {
         string utt = feature_reader.Key();
         kaldi::Matrix<BaseFloat> feature = feature_reader.Value();
@@ -160,6 +160,9 @@ int main(int argc, char* argv[]) {
         ++num_done;
     }
 
+    double elapsed = timer.Elapsed();
+    KALDI_LOG << " cost:" << elapsed << " s";
+
     KALDI_LOG << "Done " << num_done << " utterances, " << num_err
               << " with errors.";
     return (num_done != 0 ? 0 : 1);
diff --git a/speechx/examples/ds2_ol/feat/CMakeLists.txt b/speechx/examples/ds2_ol/feat/CMakeLists.txt
index db59fc8e..2d9bcb4c 100644
--- a/speechx/examples/ds2_ol/feat/CMakeLists.txt
+++ b/speechx/examples/ds2_ol/feat/CMakeLists.txt
@@ -5,8 +5,12 @@ add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
 target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
 target_link_libraries(${bin_name} frontend kaldi-util kaldi-feat-common gflags glog)
 
+set(bin_name compute_fbank_main)
+add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
+target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
+target_link_libraries(${bin_name} frontend kaldi-util kaldi-feat-common gflags glog)
 
 set(bin_name cmvn-json2kaldi)
 add_executable(${bin_name} ${CMAKE_CURRENT_SOURCE_DIR}/${bin_name}.cc)
 target_include_directories(${bin_name} PRIVATE ${SPEECHX_ROOT} ${SPEECHX_ROOT}/kaldi)
-target_link_libraries(${bin_name} utils kaldi-util kaldi-matrix gflags glog ${DEPS})
\ No newline at end of file
+target_link_libraries(${bin_name} utils kaldi-util kaldi-matrix gflags glog ${DEPS})
diff --git a/speechx/examples/ds2_ol/feat/compute_fbank_main.cc b/speechx/examples/ds2_ol/feat/compute_fbank_main.cc
new file mode 100644
index 00000000..7beaa587
--- /dev/null
+++ b/speechx/examples/ds2_ol/feat/compute_fbank_main.cc
@@ -0,0 +1,142 @@
+// Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+//
+// 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.
+
+// todo refactor, repalce with gtest
+
+#include "base/flags.h"
+#include "base/log.h"
+#include "kaldi/feat/wave-reader.h"
+#include "kaldi/util/kaldi-io.h"
+#include "kaldi/util/table-types.h"
+
+#include "frontend/audio/audio_cache.h"
+#include "frontend/audio/data_cache.h"
+#include "frontend/audio/fbank.h"
+#include "frontend/audio/feature_cache.h"
+#include "frontend/audio/frontend_itf.h"
+#include "frontend/audio/normalizer.h"
+
+DEFINE_string(wav_rspecifier, "", "test wav scp path");
+DEFINE_string(feature_wspecifier, "", "output feats wspecifier");
+DEFINE_string(cmvn_file, "", "read cmvn");
+DEFINE_double(streaming_chunk, 0.36, "streaming feature chunk size");
+DEFINE_int32(num_bins, 161, "fbank num bins");
+
+int main(int argc, char* argv[]) {
+    gflags::ParseCommandLineFlags(&argc, &argv, false);
+    google::InitGoogleLogging(argv[0]);
+
+    kaldi::SequentialTableReader<kaldi::WaveHolder> wav_reader(
+        FLAGS_wav_rspecifier);
+    kaldi::BaseFloatMatrixWriter feat_writer(FLAGS_feature_wspecifier);
+
+    int32 num_done = 0, num_err = 0;
+
+    // feature pipeline: wave cache --> povey window
+    // -->fbank --> global cmvn -> feat cache
+
+    std::unique_ptr<ppspeech::FrontendInterface> data_source(
+        new ppspeech::AudioCache(3600 * 1600, false));
+
+    ppspeech::FbankOptions opt;
+    opt.fbank_opts.frame_opts.frame_length_ms = 25;
+    opt.fbank_opts.frame_opts.frame_shift_ms = 10;
+    opt.streaming_chunk = FLAGS_streaming_chunk;
+    opt.fbank_opts.mel_opts.num_bins = FLAGS_num_bins;
+    opt.fbank_opts.frame_opts.dither = 0.0;
+
+    std::unique_ptr<ppspeech::FrontendInterface> fbank(
+        new ppspeech::Fbank(opt, std::move(data_source)));
+
+    std::unique_ptr<ppspeech::FrontendInterface> cmvn(
+        new ppspeech::CMVN(FLAGS_cmvn_file, std::move(fbank)));
+
+    ppspeech::FeatureCacheOptions feat_cache_opts;
+    // the feature cache output feature chunk by chunk.
+    // frame_chunk_size : num frame of a chunk.
+    // frame_chunk_stride: chunk sliding window stride.
+    feat_cache_opts.frame_chunk_stride = 1;
+    feat_cache_opts.frame_chunk_size = 1;
+    ppspeech::FeatureCache feature_cache(feat_cache_opts, std::move(cmvn));
+    LOG(INFO) << "feat dim: " << feature_cache.Dim();
+
+    int sample_rate = 16000;
+    float streaming_chunk = FLAGS_streaming_chunk;
+    int chunk_sample_size = streaming_chunk * sample_rate;
+    LOG(INFO) << "sr: " << sample_rate;
+    LOG(INFO) << "chunk size (s): " << streaming_chunk;
+    LOG(INFO) << "chunk size (sample): " << chunk_sample_size;
+
+    for (; !wav_reader.Done(); wav_reader.Next()) {
+        std::string utt = wav_reader.Key();
+        const kaldi::WaveData& wave_data = wav_reader.Value();
+        LOG(INFO) << "process utt: " << utt;
+
+        int32 this_channel = 0;
+        kaldi::SubVector<kaldi::BaseFloat> waveform(wave_data.Data(),
+                                                    this_channel);
+        int tot_samples = waveform.Dim();
+        LOG(INFO) << "wav len (sample): " << tot_samples;
+
+        int sample_offset = 0;
+        std::vector<kaldi::Vector<BaseFloat>> feats;
+        int feature_rows = 0;
+        while (sample_offset < tot_samples) {
+            int cur_chunk_size =
+                std::min(chunk_sample_size, tot_samples - sample_offset);
+
+            kaldi::Vector<kaldi::BaseFloat> wav_chunk(cur_chunk_size);
+            for (int i = 0; i < cur_chunk_size; ++i) {
+                wav_chunk(i) = waveform(sample_offset + i);
+            }
+
+            kaldi::Vector<BaseFloat> features;
+            feature_cache.Accept(wav_chunk);
+            if (cur_chunk_size < chunk_sample_size) {
+                feature_cache.SetFinished();
+            }
+            bool flag = true;
+            do {
+                flag = feature_cache.Read(&features);
+                feats.push_back(features);
+                feature_rows += features.Dim() / feature_cache.Dim();
+            } while (flag == true && features.Dim() != 0);
+            sample_offset += cur_chunk_size;
+        }
+
+        int cur_idx = 0;
+        kaldi::Matrix<kaldi::BaseFloat> features(feature_rows,
+                                                 feature_cache.Dim());
+        for (auto feat : feats) {
+            int num_rows = feat.Dim() / feature_cache.Dim();
+            for (int row_idx = 0; row_idx < num_rows; ++row_idx) {
+                for (size_t col_idx = 0; col_idx < feature_cache.Dim();
+                     ++col_idx) {
+                    features(cur_idx, col_idx) =
+                        feat(row_idx * feature_cache.Dim() + col_idx);
+                }
+                ++cur_idx;
+            }
+        }
+        feat_writer.Write(utt, features);
+        feature_cache.Reset();
+
+        if (num_done % 50 == 0 && num_done != 0)
+            KALDI_VLOG(2) << "Processed " << num_done << " utterances";
+        num_done++;
+    }
+    KALDI_LOG << "Done " << num_done << " utterances, " << num_err
+              << " with errors.";
+    return (num_done != 0 ? 0 : 1);
+}
diff --git a/speechx/speechx/decoder/param.h b/speechx/speechx/decoder/param.h
index ef565621..85de08ca 100644
--- a/speechx/speechx/decoder/param.h
+++ b/speechx/speechx/decoder/param.h
@@ -47,7 +47,8 @@ DEFINE_string(model_cache_names,
               "chunk_state_h_box,chunk_state_c_box",
               "model cache names");
 DEFINE_string(model_cache_shapes, "5-1-1024,5-1-1024", "model cache shapes");
-
+DEFINE_bool(use_fbank, false, "use fbank or linear feature");
+DEFINE_int32(num_bins, 161, "num bins of mel");
 
 namespace ppspeech {
 // todo refactor later
@@ -57,13 +58,21 @@ FeaturePipelineOptions InitFeaturePipelineOptions() {
     opts.linear_spectrogram_opts.streaming_chunk = FLAGS_streaming_chunk;
     opts.to_float32 = FLAGS_to_float32;
     kaldi::FrameExtractionOptions frame_opts;
-    frame_opts.frame_length_ms = 20;
-    frame_opts.frame_shift_ms = 10;
-    frame_opts.remove_dc_offset = false;
-    frame_opts.window_type = "hanning";
-    frame_opts.preemph_coeff = 0.0;
     frame_opts.dither = 0.0;
-    opts.linear_spectrogram_opts.frame_opts = frame_opts;
+    frame_opts.frame_shift_ms = 10;
+    opts.use_fbank = FLAGS_use_fbank;
+    if (opts.use_fbank) {
+      frame_opts.window_type = "povey";
+      frame_opts.frame_length_ms = 25;
+      opts.fbank_opts.fbank_opts.mel_opts.num_bins = FLAGS_num_bins;
+      opts.fbank_opts.fbank_opts.frame_opts = frame_opts;
+    } else {
+      frame_opts.remove_dc_offset = false;
+      frame_opts.frame_length_ms = 20;
+      frame_opts.window_type = "hanning";
+      frame_opts.preemph_coeff = 0.0;
+      opts.linear_spectrogram_opts.frame_opts = frame_opts;
+    }
     opts.feature_cache_opts.frame_chunk_size = FLAGS_receptive_field_length;
     opts.feature_cache_opts.frame_chunk_stride = FLAGS_downsampling_rate;
     return opts;
diff --git a/speechx/speechx/frontend/audio/CMakeLists.txt b/speechx/speechx/frontend/audio/CMakeLists.txt
index 2d20edf7..745832fe 100644
--- a/speechx/speechx/frontend/audio/CMakeLists.txt
+++ b/speechx/speechx/frontend/audio/CMakeLists.txt
@@ -7,6 +7,7 @@ add_library(frontend STATIC
   audio_cache.cc
   feature_cache.cc
   feature_pipeline.cc
+  fbank.cc
 )
 
-target_link_libraries(frontend PUBLIC kaldi-matrix kaldi-feat-common)
+target_link_libraries(frontend PUBLIC kaldi-matrix kaldi-feat-common kaldi-fbank)
diff --git a/speechx/speechx/frontend/audio/fbank.cc b/speechx/speechx/frontend/audio/fbank.cc
index 8273beec..a865db59 100644
--- a/speechx/speechx/frontend/audio/fbank.cc
+++ b/speechx/speechx/frontend/audio/fbank.cc
@@ -29,14 +29,16 @@ using kaldi::VectorBase;
 using kaldi::Matrix;
 using std::vector;
 
+// todo refactor later:(SmileGoat)
+
 Fbank::Fbank(const FbankOptions& opts,
              std::unique_ptr<FrontendInterface> base_extractor)
     : opts_(opts),
       computer_(opts.fbank_opts),
-      window_function_(computer_.GetFrameOptions()) {
+      window_function_(opts.fbank_opts.frame_opts) {
     base_extractor_ = std::move(base_extractor);
-    chunk_sample_size_ =
-        static_cast<int32>(opts.streaming_chunk * opts.frame_opts.samp_freq);
+    chunk_sample_size_ = static_cast<int32>(
+        opts.streaming_chunk * opts.fbank_opts.frame_opts.samp_freq);
 }
 
 void Fbank::Accept(const VectorBase<BaseFloat>& inputs) {
@@ -71,7 +73,8 @@ bool Fbank::Read(Vector<BaseFloat>* feats) {
 
 // Compute spectrogram feat
 bool Fbank::Compute(const Vector<BaseFloat>& waves, Vector<BaseFloat>* feats) {
-    const FrameExtractionOptions& frame_opts = computer_.GetFrameOptions();
+    const kaldi::FrameExtractionOptions& frame_opts =
+        computer_.GetFrameOptions();
     int32 num_samples = waves.Dim();
     int32 frame_length = frame_opts.WindowSize();
     int32 sample_rate = frame_opts.samp_freq;
@@ -80,7 +83,7 @@ bool Fbank::Compute(const Vector<BaseFloat>& waves, Vector<BaseFloat>* feats) {
     }
 
     int32 num_frames = kaldi::NumFrames(num_samples, frame_opts);
-    feats->Rsize(num_frames * Dim());
+    feats->Resize(num_frames * Dim());
 
     Vector<BaseFloat> window;
     bool need_raw_log_energy = computer_.NeedRawLogEnergy();
@@ -95,14 +98,24 @@ bool Fbank::Compute(const Vector<BaseFloat>& waves, Vector<BaseFloat>* feats) {
                              need_raw_log_energy ? &raw_log_energy : NULL);
 
 
-        Vector<BaseFloat> this_feature(computer_.Dim(), kUndefined);
+        Vector<BaseFloat> this_feature(computer_.Dim(), kaldi::kUndefined);
         // note: this online feature-extraction code does not support VTLN.
-        BaseFloat vtln_warp = 1.0;
-        computer_.Compute(raw_log_energy, vtln_warp, &window, &this_feature);
+        RealFft(&window, true);
+        kaldi::ComputePowerSpectrum(&window);
+        const kaldi::MelBanks &mel_bank = *(computer_.GetMelBanks(1.0));
+        SubVector<BaseFloat> power_spectrum(window, 0, window.Dim() / 2 + 1); 
+        if (!opts_.fbank_opts.use_power) {
+            power_spectrum.ApplyPow(0.5);
+        }
+        int32 mel_offset = ((opts_.fbank_opts.use_energy && !opts_.fbank_opts.htk_compat) ? 1 : 0);
+        SubVector<BaseFloat> mel_energies(this_feature, mel_offset, opts_.fbank_opts.mel_opts.num_bins);
+        mel_bank.Compute(power_spectrum, &mel_energies);
+        mel_energies.ApplyFloor(1e-07);
+        mel_energies.ApplyLog();
         SubVector<BaseFloat> output_row(feats->Data() + frame * Dim(), Dim());
         output_row.CopyFromVec(this_feature);
     }
     return true;
 }
 
-}  // namespace ppspeech
\ No newline at end of file
+}  // namespace ppspeech
diff --git a/speechx/speechx/frontend/audio/fbank.h b/speechx/speechx/frontend/audio/fbank.h
index 3b71ff84..66957dc6 100644
--- a/speechx/speechx/frontend/audio/fbank.h
+++ b/speechx/speechx/frontend/audio/fbank.h
@@ -14,6 +14,8 @@
 
 #pragma once
 
+#include "base/common.h"
+#include "frontend/audio/frontend_itf.h"
 #include "kaldi/feat/feature-fbank.h"
 #include "kaldi/feat/feature-mfcc.h"
 #include "kaldi/matrix/kaldi-vector.h"
@@ -38,7 +40,7 @@ struct FbankOptions {
 class Fbank : public FrontendInterface {
   public:
     explicit Fbank(const FbankOptions& opts,
-                   unique_ptr<FrontendInterface> base_extractor);
+                   std::unique_ptr<FrontendInterface> base_extractor);
     virtual void Accept(const kaldi::VectorBase<kaldi::BaseFloat>& inputs);
     virtual bool Read(kaldi::Vector<kaldi::BaseFloat>* feats);
 
@@ -61,15 +63,15 @@ class Fbank : public FrontendInterface {
     FbankOptions opts_;
     std::unique_ptr<FrontendInterface> base_extractor_;
 
-
-    FeatureWindowFunction window_function_;
+    kaldi::FeatureWindowFunction window_function_;
     kaldi::FbankComputer computer_;
     // features_ is the Mfcc or Plp or Fbank features that we have already
     // computed.
     kaldi::Vector<kaldi::BaseFloat> features_;
     kaldi::Vector<kaldi::BaseFloat> remained_wav_;
+    kaldi::int32 chunk_sample_size_;
 
     DISALLOW_COPY_AND_ASSIGN(Fbank);
 };
 
-}  // namespace ppspeech
\ No newline at end of file
+}  // namespace ppspeech
diff --git a/speechx/speechx/frontend/audio/feature_pipeline.cc b/speechx/speechx/frontend/audio/feature_pipeline.cc
index 5914fedb..40891871 100644
--- a/speechx/speechx/frontend/audio/feature_pipeline.cc
+++ b/speechx/speechx/frontend/audio/feature_pipeline.cc
@@ -22,12 +22,18 @@ FeaturePipeline::FeaturePipeline(const FeaturePipelineOptions& opts) {
     unique_ptr<FrontendInterface> data_source(
         new ppspeech::AudioCache(1000 * kint16max, opts.to_float32));
 
-    unique_ptr<FrontendInterface> linear_spectrogram(
-        new ppspeech::LinearSpectrogram(opts.linear_spectrogram_opts,
-                                        std::move(data_source)));
+    unique_ptr<FrontendInterface> base_feature;
+    
+    if (opts.use_fbank) {
+        base_feature.reset(new ppspeech::Fbank(opts.fbank_opts,
+                              std::move(data_source)));
+    } else {
+        base_feature.reset(new ppspeech::LinearSpectrogram(opts.linear_spectrogram_opts,
+                              std::move(data_source)));
+    }
 
     unique_ptr<FrontendInterface> cmvn(
-        new ppspeech::CMVN(opts.cmvn_file, std::move(linear_spectrogram)));
+        new ppspeech::CMVN(opts.cmvn_file, std::move(base_feature)));
 
     base_extractor_.reset(
         new ppspeech::FeatureCache(opts.feature_cache_opts, std::move(cmvn)));
diff --git a/speechx/speechx/frontend/audio/feature_pipeline.h b/speechx/speechx/frontend/audio/feature_pipeline.h
index 580c02fa..4868d37e 100644
--- a/speechx/speechx/frontend/audio/feature_pipeline.h
+++ b/speechx/speechx/frontend/audio/feature_pipeline.h
@@ -21,6 +21,7 @@
 #include "frontend/audio/feature_cache.h"
 #include "frontend/audio/frontend_itf.h"
 #include "frontend/audio/linear_spectrogram.h"
+#include "frontend/audio/fbank.h"
 #include "frontend/audio/normalizer.h"
 
 namespace ppspeech {
@@ -28,12 +29,16 @@ namespace ppspeech {
 struct FeaturePipelineOptions {
     std::string cmvn_file;
     bool to_float32;
+    bool use_fbank;
     LinearSpectrogramOptions linear_spectrogram_opts;
+    FbankOptions fbank_opts;
     FeatureCacheOptions feature_cache_opts;
     FeaturePipelineOptions()
         : cmvn_file(""),
           to_float32(false),
+          use_fbank(false),
           linear_spectrogram_opts(),
+          fbank_opts(),
           feature_cache_opts() {}
 };
 
diff --git a/speechx/speechx/kaldi/feat/CMakeLists.txt b/speechx/speechx/kaldi/feat/CMakeLists.txt
index c3a996ff..cfbf2025 100644
--- a/speechx/speechx/kaldi/feat/CMakeLists.txt
+++ b/speechx/speechx/kaldi/feat/CMakeLists.txt
@@ -3,10 +3,10 @@ add_library(kaldi-mfcc
 )
 target_link_libraries(kaldi-mfcc PUBLIC kaldi-feat-common)
 
-add_library(fbank
+add_library(kaldi-fbank
   feature-fbank.cc
 )
-target_link_libraries(fbank PUBLIC kaldi-feat-common)
+target_link_libraries(kaldi-fbank PUBLIC kaldi-feat-common)
 
 add_library(kaldi-feat-common
   wave-reader.cc
diff --git a/speechx/speechx/kaldi/feat/feature-fbank.h b/speechx/speechx/kaldi/feat/feature-fbank.h
index f57d185a..d121cc0e 100644
--- a/speechx/speechx/kaldi/feat/feature-fbank.h
+++ b/speechx/speechx/kaldi/feat/feature-fbank.h
@@ -128,8 +128,8 @@ class FbankComputer {
 
   ~FbankComputer();
 
- private:
   const MelBanks *GetMelBanks(BaseFloat vtln_warp);
+ private:
 
 
   FbankOptions opts_;
diff --git a/speechx/speechx/kaldi/feat/mel-computations.cc b/speechx/speechx/kaldi/feat/mel-computations.cc
index bb5e9f9a..626cb677 100644
--- a/speechx/speechx/kaldi/feat/mel-computations.cc
+++ b/speechx/speechx/kaldi/feat/mel-computations.cc
@@ -120,8 +120,8 @@ MelBanks::MelBanks(const MelBanksOptions &opts,
         last_index = i;
       }
     }
-    KALDI_ASSERT(first_index != -1 && last_index >= first_index
-                 && "You may have set --num-mel-bins too large.");
+    //KALDI_ASSERT(first_index != -1 && last_index >= first_index
+    //             && "You may have set --num-mel-bins too large.");
 
     bins_[bin].first = first_index;
     int32 size = last_index + 1 - first_index;