You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
63 lines
2.0 KiB
63 lines
2.0 KiB
// 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.
|
|
|
|
#include "frontend/audio/fbank.h"
|
|
|
|
#include "kaldi/base/kaldi-math.h"
|
|
#include "kaldi/feat/feature-common.h"
|
|
#include "kaldi/feat/feature-functions.h"
|
|
#include "kaldi/matrix/matrix-functions.h"
|
|
|
|
namespace ppspeech {
|
|
|
|
using kaldi::BaseFloat;
|
|
using kaldi::int32;
|
|
using kaldi::Matrix;
|
|
using kaldi::SubVector;
|
|
using kaldi::Vector;
|
|
using kaldi::VectorBase;
|
|
using std::vector;
|
|
|
|
FbankComputer::FbankComputer(const Options& opts)
|
|
: opts_(opts), computer_(opts) {}
|
|
|
|
int32 FbankComputer::Dim() const {
|
|
return opts_.mel_opts.num_bins + (opts_.use_energy ? 1 : 0);
|
|
}
|
|
|
|
bool FbankComputer::NeedRawLogEnergy() {
|
|
return opts_.use_energy && opts_.raw_energy;
|
|
}
|
|
|
|
// Compute feat
|
|
bool FbankComputer::Compute(Vector<BaseFloat>* window,
|
|
Vector<BaseFloat>* feat) {
|
|
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_.use_power) {
|
|
power_spectrum.ApplyPow(0.5);
|
|
}
|
|
int32 mel_offset = ((opts_.use_energy && !opts_.htk_compat) ? 1 : 0);
|
|
SubVector<BaseFloat> mel_energies(
|
|
*feat, mel_offset, opts_.mel_opts.num_bins);
|
|
mel_bank.Compute(power_spectrum, &mel_energies);
|
|
mel_energies.ApplyFloor(1e-07);
|
|
mel_energies.ApplyLog();
|
|
return true;
|
|
}
|
|
|
|
} // namespace ppspeech
|