online-feature.cc
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// feat/online-feature.cc
// Copyright 2013 Johns Hopkins University (author: Daniel Povey)
// 2014 Yanqing Sun, Junjie Wang,
// Daniel Povey, Korbinian Riedhammer
// See ../../COPYING for clarification regarding multiple authors
//
// 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
//
// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
// MERCHANTABLITY OR NON-INFRINGEMENT.
// See the Apache 2 License for the specific language governing permissions and
// limitations under the License.
#include "feat/online-feature.h"
#include "transform/cmvn.h"
namespace kaldi {
RecyclingVector::RecyclingVector(int items_to_hold):
items_to_hold_(items_to_hold == 0 ? -1 : items_to_hold),
first_available_index_(0) {
}
RecyclingVector::~RecyclingVector() {
for (auto *item : items_) {
delete item;
}
}
Vector<BaseFloat> *RecyclingVector::At(int index) const {
if (index < first_available_index_) {
KALDI_ERR << "Attempted to retrieve feature vector that was "
"already removed by the RecyclingVector (index = "
<< index << "; "
<< "first_available_index = " << first_available_index_ << "; "
<< "size = " << Size() << ")";
}
// 'at' does size checking.
return items_.at(index - first_available_index_);
}
void RecyclingVector::PushBack(Vector<BaseFloat> *item) {
if (items_.size() == items_to_hold_) {
delete items_.front();
items_.pop_front();
++first_available_index_;
}
items_.push_back(item);
}
int RecyclingVector::Size() const {
return first_available_index_ + items_.size();
}
template <class C>
void OnlineGenericBaseFeature<C>::GetFrame(int32 frame,
VectorBase<BaseFloat> *feat) {
feat->CopyFromVec(*(features_.At(frame)));
};
template <class C>
OnlineGenericBaseFeature<C>::OnlineGenericBaseFeature(
const typename C::Options &opts):
computer_(opts), window_function_(computer_.GetFrameOptions()),
features_(opts.frame_opts.max_feature_vectors),
input_finished_(false), waveform_offset_(0) { }
template <class C>
void OnlineGenericBaseFeature<C>::MaybeCreateResampler(
BaseFloat sampling_rate) {
BaseFloat expected_sampling_rate = computer_.GetFrameOptions().samp_freq;
if (resampler_ != nullptr) {
KALDI_ASSERT(resampler_->GetInputSamplingRate() == sampling_rate);
KALDI_ASSERT(resampler_->GetOutputSamplingRate() == expected_sampling_rate);
} else if (((sampling_rate > expected_sampling_rate) &&
!computer_.GetFrameOptions().allow_downsample) ||
((sampling_rate > expected_sampling_rate) &&
!computer_.GetFrameOptions().allow_upsample)) {
resampler_.reset(new LinearResample(
sampling_rate, expected_sampling_rate,
std::min(sampling_rate / 2, expected_sampling_rate / 2), 6));
} else if (sampling_rate != expected_sampling_rate) {
KALDI_ERR << "Sampling frequency mismatch, expected "
<< expected_sampling_rate << ", got " << sampling_rate
<< "\nPerhaps you want to use the options "
"--allow_{upsample,downsample}";
}
}
template <class C>
void OnlineGenericBaseFeature<C>::InputFinished() {
if (resampler_ != nullptr) {
// There may be a few samples left once we flush the resampler_ object, telling it
// that the file has finished. This should rarely make any difference.
Vector<BaseFloat> appended_wave;
Vector<BaseFloat> resampled_wave;
resampler_->Resample(appended_wave, true, &resampled_wave);
if (resampled_wave.Dim() != 0) {
appended_wave.Resize(waveform_remainder_.Dim() +
resampled_wave.Dim());
if (waveform_remainder_.Dim() != 0)
appended_wave.Range(0, waveform_remainder_.Dim())
.CopyFromVec(waveform_remainder_);
appended_wave.Range(waveform_remainder_.Dim(), resampled_wave.Dim())
.CopyFromVec(resampled_wave);
waveform_remainder_.Swap(&appended_wave);
}
}
input_finished_ = true;
ComputeFeatures();
}
template <class C>
void OnlineGenericBaseFeature<C>::AcceptWaveform(
BaseFloat sampling_rate, const VectorBase<BaseFloat> &original_waveform) {
if (original_waveform.Dim() == 0)
return; // Nothing to do.
if (input_finished_)
KALDI_ERR << "AcceptWaveform called after InputFinished() was called.";
Vector<BaseFloat> appended_wave;
Vector<BaseFloat> resampled_wave;
const VectorBase<BaseFloat> *waveform;
MaybeCreateResampler(sampling_rate);
if (resampler_ == nullptr) {
waveform = &original_waveform;
} else {
resampler_->Resample(original_waveform, false, &resampled_wave);
waveform = &resampled_wave;
}
appended_wave.Resize(waveform_remainder_.Dim() + waveform->Dim());
if (waveform_remainder_.Dim() != 0)
appended_wave.Range(0, waveform_remainder_.Dim())
.CopyFromVec(waveform_remainder_);
appended_wave.Range(waveform_remainder_.Dim(), waveform->Dim())
.CopyFromVec(*waveform);
waveform_remainder_.Swap(&appended_wave);
ComputeFeatures();
}
template <class C>
void OnlineGenericBaseFeature<C>::ComputeFeatures() {
const FrameExtractionOptions &frame_opts = computer_.GetFrameOptions();
int64 num_samples_total = waveform_offset_ + waveform_remainder_.Dim();
int32 num_frames_old = features_.Size(),
num_frames_new = NumFrames(num_samples_total, frame_opts,
input_finished_);
KALDI_ASSERT(num_frames_new >= num_frames_old);
Vector<BaseFloat> window;
bool need_raw_log_energy = computer_.NeedRawLogEnergy();
for (int32 frame = num_frames_old; frame < num_frames_new; frame++) {
BaseFloat raw_log_energy = 0.0;
ExtractWindow(waveform_offset_, waveform_remainder_, frame,
frame_opts, window_function_, &window,
need_raw_log_energy ? &raw_log_energy : NULL);
Vector<BaseFloat> *this_feature = new Vector<BaseFloat>(computer_.Dim(),
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);
features_.PushBack(this_feature);
}
// OK, we will now discard any portion of the signal that will not be
// necessary to compute frames in the future.
int64 first_sample_of_next_frame = FirstSampleOfFrame(num_frames_new,
frame_opts);
int32 samples_to_discard = first_sample_of_next_frame - waveform_offset_;
if (samples_to_discard > 0) {
// discard the leftmost part of the waveform that we no longer need.
int32 new_num_samples = waveform_remainder_.Dim() - samples_to_discard;
if (new_num_samples <= 0) {
// odd, but we'll try to handle it.
waveform_offset_ += waveform_remainder_.Dim();
waveform_remainder_.Resize(0);
} else {
Vector<BaseFloat> new_remainder(new_num_samples);
new_remainder.CopyFromVec(waveform_remainder_.Range(samples_to_discard,
new_num_samples));
waveform_offset_ += samples_to_discard;
waveform_remainder_.Swap(&new_remainder);
}
}
}
// instantiate the templates defined here for MFCC, PLP and filterbank classes.
template class OnlineGenericBaseFeature<MfccComputer>;
template class OnlineGenericBaseFeature<PlpComputer>;
template class OnlineGenericBaseFeature<FbankComputer>;
OnlineCmvnState::OnlineCmvnState(const OnlineCmvnState &other):
speaker_cmvn_stats(other.speaker_cmvn_stats),
global_cmvn_stats(other.global_cmvn_stats),
frozen_state(other.frozen_state) { }
void OnlineCmvnState::Write(std::ostream &os, bool binary) const {
WriteToken(os, binary, "<OnlineCmvnState>"); // magic string.
WriteToken(os, binary, "<SpeakerCmvnStats>");
speaker_cmvn_stats.Write(os, binary);
WriteToken(os, binary, "<GlobalCmvnStats>");
global_cmvn_stats.Write(os, binary);
WriteToken(os, binary, "<FrozenState>");
frozen_state.Write(os, binary);
WriteToken(os, binary, "</OnlineCmvnState>");
}
void OnlineCmvnState::Read(std::istream &is, bool binary) {
ExpectToken(is, binary, "<OnlineCmvnState>"); // magic string.
ExpectToken(is, binary, "<SpeakerCmvnStats>");
speaker_cmvn_stats.Read(is, binary);
ExpectToken(is, binary, "<GlobalCmvnStats>");
global_cmvn_stats.Read(is, binary);
ExpectToken(is, binary, "<FrozenState>");
frozen_state.Read(is, binary);
ExpectToken(is, binary, "</OnlineCmvnState>");
}
OnlineCmvn::OnlineCmvn(const OnlineCmvnOptions &opts,
const OnlineCmvnState &cmvn_state,
OnlineFeatureInterface *src):
opts_(opts), temp_stats_(2, src->Dim() + 1),
temp_feats_(src->Dim()), temp_feats_dbl_(src->Dim()),
src_(src) {
SetState(cmvn_state);
if (!SplitStringToIntegers(opts.skip_dims, ":", false, &skip_dims_))
KALDI_ERR << "Bad --skip-dims option (should be colon-separated list of "
<< "integers)";
}
OnlineCmvn::OnlineCmvn(const OnlineCmvnOptions &opts,
OnlineFeatureInterface *src):
opts_(opts), temp_stats_(2, src->Dim() + 1),
temp_feats_(src->Dim()), temp_feats_dbl_(src->Dim()),
src_(src) {
if (!SplitStringToIntegers(opts.skip_dims, ":", false, &skip_dims_))
KALDI_ERR << "Bad --skip-dims option (should be colon-separated list of "
<< "integers)";
}
void OnlineCmvn::GetMostRecentCachedFrame(int32 frame,
int32 *cached_frame,
MatrixBase<double> *stats) {
KALDI_ASSERT(frame >= 0);
InitRingBufferIfNeeded();
// look for a cached frame on a previous frame as close as possible in time
// to "frame". Return if we get one.
for (int32 t = frame; t >= 0 && t >= frame - opts_.ring_buffer_size; t--) {
if (t % opts_.modulus == 0) {
// if this frame should be cached in cached_stats_modulo_, then
// we'll look there, and we won't go back any further in time.
break;
}
int32 index = t % opts_.ring_buffer_size;
if (cached_stats_ring_[index].first == t) {
*cached_frame = t;
stats->CopyFromMat(cached_stats_ring_[index].second);
return;
}
}
int32 n = frame / opts_.modulus;
if (n >= cached_stats_modulo_.size()) {
if (cached_stats_modulo_.size() == 0) {
*cached_frame = -1;
stats->SetZero();
return;
} else {
n = static_cast<int32>(cached_stats_modulo_.size() - 1);
}
}
*cached_frame = n * opts_.modulus;
KALDI_ASSERT(cached_stats_modulo_[n] != NULL);
stats->CopyFromMat(*(cached_stats_modulo_[n]));
}
// Initialize ring buffer for caching stats.
void OnlineCmvn::InitRingBufferIfNeeded() {
if (cached_stats_ring_.empty() && opts_.ring_buffer_size > 0) {
Matrix<double> temp(2, this->Dim() + 1);
cached_stats_ring_.resize(opts_.ring_buffer_size,
std::pair<int32, Matrix<double> >(-1, temp));
}
}
void OnlineCmvn::CacheFrame(int32 frame, const MatrixBase<double> &stats) {
KALDI_ASSERT(frame >= 0);
if (frame % opts_.modulus == 0) { // store in cached_stats_modulo_.
int32 n = frame / opts_.modulus;
if (n >= cached_stats_modulo_.size()) {
// The following assert is a limitation on in what order you can call
// CacheFrame. Fortunately the calling code always calls it in sequence,
// which it has to because you need a previous frame to compute the
// current one.
KALDI_ASSERT(n == cached_stats_modulo_.size());
cached_stats_modulo_.push_back(new Matrix<double>(stats));
} else {
KALDI_WARN << "Did not expect to reach this part of code.";
// do what seems right, but we shouldn't get here.
cached_stats_modulo_[n]->CopyFromMat(stats);
}
} else { // store in the ring buffer.
InitRingBufferIfNeeded();
if (!cached_stats_ring_.empty()) {
int32 index = frame % cached_stats_ring_.size();
cached_stats_ring_[index].first = frame;
cached_stats_ring_[index].second.CopyFromMat(stats);
}
}
}
OnlineCmvn::~OnlineCmvn() {
for (size_t i = 0; i < cached_stats_modulo_.size(); i++)
delete cached_stats_modulo_[i];
cached_stats_modulo_.clear();
}
void OnlineCmvn::ComputeStatsForFrame(int32 frame,
MatrixBase<double> *stats_out) {
KALDI_ASSERT(frame >= 0 && frame < src_->NumFramesReady());
int32 dim = this->Dim(), cur_frame;
GetMostRecentCachedFrame(frame, &cur_frame, stats_out);
Vector<BaseFloat> &feats(temp_feats_);
Vector<double> &feats_dbl(temp_feats_dbl_);
while (cur_frame < frame) {
cur_frame++;
src_->GetFrame(cur_frame, &feats);
feats_dbl.CopyFromVec(feats);
stats_out->Row(0).Range(0, dim).AddVec(1.0, feats_dbl);
if (opts_.normalize_variance)
stats_out->Row(1).Range(0, dim).AddVec2(1.0, feats_dbl);
(*stats_out)(0, dim) += 1.0;
// it's a sliding buffer; a frame at the back may be
// leaving the buffer so we have to subtract that.
int32 prev_frame = cur_frame - opts_.cmn_window;
if (prev_frame >= 0) {
// we need to subtract frame prev_f from the stats.
src_->GetFrame(prev_frame, &feats);
feats_dbl.CopyFromVec(feats);
stats_out->Row(0).Range(0, dim).AddVec(-1.0, feats_dbl);
if (opts_.normalize_variance)
stats_out->Row(1).Range(0, dim).AddVec2(-1.0, feats_dbl);
(*stats_out)(0, dim) -= 1.0;
}
CacheFrame(cur_frame, (*stats_out));
}
}
// static
void OnlineCmvn::SmoothOnlineCmvnStats(const MatrixBase<double> &speaker_stats,
const MatrixBase<double> &global_stats,
const OnlineCmvnOptions &opts,
MatrixBase<double> *stats) {
if (speaker_stats.NumRows() == 2 && !opts.normalize_variance) {
// this is just for efficiency: don't operate on the variance if it's not
// needed.
int32 cols = speaker_stats.NumCols(); // dim + 1
SubMatrix<double> stats_temp(*stats, 0, 1, 0, cols);
SmoothOnlineCmvnStats(speaker_stats.RowRange(0, 1),
global_stats.RowRange(0, 1),
opts, &stats_temp);
return;
}
int32 dim = stats->NumCols() - 1;
double cur_count = (*stats)(0, dim);
// If count exceeded cmn_window it would be an error in how "window_stats"
// was accumulated.
KALDI_ASSERT(cur_count <= 1.001 * opts.cmn_window);
if (cur_count >= opts.cmn_window)
return;
if (speaker_stats.NumRows() != 0) { // if we have speaker stats..
double count_from_speaker = opts.cmn_window - cur_count,
speaker_count = speaker_stats(0, dim);
if (count_from_speaker > opts.speaker_frames)
count_from_speaker = opts.speaker_frames;
if (count_from_speaker > speaker_count)
count_from_speaker = speaker_count;
if (count_from_speaker > 0.0)
stats->AddMat(count_from_speaker / speaker_count,
speaker_stats);
cur_count = (*stats)(0, dim);
}
if (cur_count >= opts.cmn_window)
return;
if (global_stats.NumRows() != 0) {
double count_from_global = opts.cmn_window - cur_count,
global_count = global_stats(0, dim);
KALDI_ASSERT(global_count > 0.0);
if (count_from_global > opts.global_frames)
count_from_global = opts.global_frames;
if (count_from_global > 0.0)
stats->AddMat(count_from_global / global_count,
global_stats);
} else {
KALDI_ERR << "Global CMN stats are required";
}
}
void OnlineCmvn::GetFrame(int32 frame,
VectorBase<BaseFloat> *feat) {
src_->GetFrame(frame, feat);
KALDI_ASSERT(feat->Dim() == this->Dim());
int32 dim = feat->Dim();
Matrix<double> &stats(temp_stats_);
stats.Resize(2, dim + 1, kUndefined); // Will do nothing if size was correct.
if (frozen_state_.NumRows() != 0) { // the CMVN state has been frozen.
stats.CopyFromMat(frozen_state_);
} else {
// first get the raw CMVN stats (this involves caching..)
this->ComputeStatsForFrame(frame, &stats);
// now smooth them.
SmoothOnlineCmvnStats(orig_state_.speaker_cmvn_stats,
orig_state_.global_cmvn_stats,
opts_,
&stats);
}
if (!skip_dims_.empty())
FakeStatsForSomeDims(skip_dims_, &stats);
// call the function ApplyCmvn declared in ../transform/cmvn.h, which
// requires a matrix.
// 1 row; num-cols == dim; stride == dim.
SubMatrix<BaseFloat> feat_mat(feat->Data(), 1, dim, dim);
// the function ApplyCmvn takes a matrix, so form a one-row matrix to give it.
if (opts_.normalize_mean)
ApplyCmvn(stats, opts_.normalize_variance, &feat_mat);
else
KALDI_ASSERT(!opts_.normalize_variance);
}
void OnlineCmvn::Freeze(int32 cur_frame) {
int32 dim = this->Dim();
Matrix<double> stats(2, dim + 1);
// get the raw CMVN stats
this->ComputeStatsForFrame(cur_frame, &stats);
// now smooth them.
SmoothOnlineCmvnStats(orig_state_.speaker_cmvn_stats,
orig_state_.global_cmvn_stats,
opts_,
&stats);
this->frozen_state_ = stats;
}
void OnlineCmvn::GetState(int32 cur_frame,
OnlineCmvnState *state_out) {
*state_out = this->orig_state_;
{ // This block updates state_out->speaker_cmvn_stats
int32 dim = this->Dim();
if (state_out->speaker_cmvn_stats.NumRows() == 0)
state_out->speaker_cmvn_stats.Resize(2, dim + 1);
Vector<BaseFloat> feat(dim);
Vector<double> feat_dbl(dim);
for (int32 t = 0; t <= cur_frame; t++) {
src_->GetFrame(t, &feat);
feat_dbl.CopyFromVec(feat);
state_out->speaker_cmvn_stats(0, dim) += 1.0;
state_out->speaker_cmvn_stats.Row(0).Range(0, dim).AddVec(1.0, feat_dbl);
state_out->speaker_cmvn_stats.Row(1).Range(0, dim).AddVec2(1.0, feat_dbl);
}
}
// Store any frozen state (the effect of the user possibly
// having called Freeze().
state_out->frozen_state = frozen_state_;
}
void OnlineCmvn::SetState(const OnlineCmvnState &cmvn_state) {
KALDI_ASSERT(cached_stats_modulo_.empty() &&
"You cannot call SetState() after processing data.");
orig_state_ = cmvn_state;
frozen_state_ = cmvn_state.frozen_state;
}
int32 OnlineSpliceFrames::NumFramesReady() const {
int32 num_frames = src_->NumFramesReady();
if (num_frames > 0 && src_->IsLastFrame(num_frames - 1))
return num_frames;
else
return std::max<int32>(0, num_frames - right_context_);
}
void OnlineSpliceFrames::GetFrame(int32 frame, VectorBase<BaseFloat> *feat) {
KALDI_ASSERT(left_context_ >= 0 && right_context_ >= 0);
KALDI_ASSERT(frame >= 0 && frame < NumFramesReady());
int32 dim_in = src_->Dim();
KALDI_ASSERT(feat->Dim() == dim_in * (1 + left_context_ + right_context_));
int32 T = src_->NumFramesReady();
for (int32 t2 = frame - left_context_; t2 <= frame + right_context_; t2++) {
int32 t2_limited = t2;
if (t2_limited < 0) t2_limited = 0;
if (t2_limited >= T) t2_limited = T - 1;
int32 n = t2 - (frame - left_context_); // 0 for left-most frame,
// increases to the right.
SubVector<BaseFloat> part(*feat, n * dim_in, dim_in);
src_->GetFrame(t2_limited, &part);
}
}
OnlineTransform::OnlineTransform(const MatrixBase<BaseFloat> &transform,
OnlineFeatureInterface *src):
src_(src) {
int32 src_dim = src_->Dim();
if (transform.NumCols() == src_dim) { // Linear transform
linear_term_ = transform;
offset_.Resize(transform.NumRows()); // Resize() will zero it.
} else if (transform.NumCols() == src_dim + 1) { // Affine transform
linear_term_ = transform.Range(0, transform.NumRows(), 0, src_dim);
offset_.Resize(transform.NumRows());
offset_.CopyColFromMat(transform, src_dim);
} else {
KALDI_ERR << "Dimension mismatch: source features have dimension "
<< src_dim << " and LDA #cols is " << transform.NumCols();
}
}
void OnlineTransform::GetFrame(int32 frame, VectorBase<BaseFloat> *feat) {
Vector<BaseFloat> input_feat(linear_term_.NumCols());
src_->GetFrame(frame, &input_feat);
feat->CopyFromVec(offset_);
feat->AddMatVec(1.0, linear_term_, kNoTrans, input_feat, 1.0);
}
void OnlineTransform::GetFrames(
const std::vector<int32> &frames, MatrixBase<BaseFloat> *feats) {
KALDI_ASSERT(static_cast<int32>(frames.size()) == feats->NumRows());
int32 num_frames = feats->NumRows(),
input_dim = linear_term_.NumCols();
Matrix<BaseFloat> input_feats(num_frames, input_dim, kUndefined);
src_->GetFrames(frames, &input_feats);
feats->CopyRowsFromVec(offset_);
feats->AddMatMat(1.0, input_feats, kNoTrans, linear_term_, kTrans, 1.0);
}
int32 OnlineDeltaFeature::Dim() const {
int32 src_dim = src_->Dim();
return src_dim * (1 + opts_.order);
}
int32 OnlineDeltaFeature::NumFramesReady() const {
int32 num_frames = src_->NumFramesReady(),
context = opts_.order * opts_.window;
// "context" is the number of frames on the left or (more relevant
// here) right which we need in order to produce the output.
if (num_frames > 0 && src_->IsLastFrame(num_frames-1))
return num_frames;
else
return std::max<int32>(0, num_frames - context);
}
void OnlineDeltaFeature::GetFrame(int32 frame,
VectorBase<BaseFloat> *feat) {
KALDI_ASSERT(frame >= 0 && frame < NumFramesReady());
KALDI_ASSERT(feat->Dim() == Dim());
// We'll produce a temporary matrix containing the features we want to
// compute deltas on, but truncated to the necessary context.
int32 context = opts_.order * opts_.window;
int32 left_frame = frame - context,
right_frame = frame + context,
src_frames_ready = src_->NumFramesReady();
if (left_frame < 0) left_frame = 0;
if (right_frame >= src_frames_ready)
right_frame = src_frames_ready - 1;
KALDI_ASSERT(right_frame >= left_frame);
int32 temp_num_frames = right_frame + 1 - left_frame,
src_dim = src_->Dim();
Matrix<BaseFloat> temp_src(temp_num_frames, src_dim);
for (int32 t = left_frame; t <= right_frame; t++) {
SubVector<BaseFloat> temp_row(temp_src, t - left_frame);
src_->GetFrame(t, &temp_row);
}
int32 temp_t = frame - left_frame; // temp_t is the offset of frame "frame"
// within temp_src
delta_features_.Process(temp_src, temp_t, feat);
}
OnlineDeltaFeature::OnlineDeltaFeature(const DeltaFeaturesOptions &opts,
OnlineFeatureInterface *src):
src_(src), opts_(opts), delta_features_(opts) { }
void OnlineCacheFeature::GetFrame(int32 frame, VectorBase<BaseFloat> *feat) {
KALDI_ASSERT(frame >= 0);
if (static_cast<size_t>(frame) < cache_.size() && cache_[frame] != NULL) {
feat->CopyFromVec(*(cache_[frame]));
} else {
if (static_cast<size_t>(frame) >= cache_.size())
cache_.resize(frame + 1, NULL);
int32 dim = this->Dim();
cache_[frame] = new Vector<BaseFloat>(dim);
// The following call will crash if frame "frame" is not ready.
src_->GetFrame(frame, cache_[frame]);
feat->CopyFromVec(*(cache_[frame]));
}
}
void OnlineCacheFeature::GetFrames(
const std::vector<int32> &frames, MatrixBase<BaseFloat> *feats) {
int32 num_frames = frames.size();
// non_cached_frames will be the subset of 't' values in 'frames' which were
// not previously cached, which we therefore need to get from src_.
std::vector<int32> non_cached_frames;
// 'non_cached_indexes' stores the indexes 'i' into 'frames' corresponding to
// the corresponding frames in 'non_cached_frames'.
std::vector<int32> non_cached_indexes;
non_cached_frames.reserve(frames.size());
non_cached_indexes.reserve(frames.size());
for (int32 i = 0; i < num_frames; i++) {
int32 t = frames[i];
if (static_cast<size_t>(t) < cache_.size() && cache_[t] != NULL) {
feats->Row(i).CopyFromVec(*(cache_[t]));
} else {
non_cached_frames.push_back(t);
non_cached_indexes.push_back(i);
}
}
if (non_cached_frames.empty())
return;
int32 num_non_cached_frames = non_cached_frames.size(),
dim = this->Dim();
Matrix<BaseFloat> non_cached_feats(num_non_cached_frames, dim,
kUndefined);
src_->GetFrames(non_cached_frames, &non_cached_feats);
for (int32 i = 0; i < num_non_cached_frames; i++) {
int32 t = non_cached_frames[i];
if (static_cast<size_t>(t) < cache_.size() && cache_[t] != NULL) {
// We can reach this point due to repeat indexes in 'non_cached_frames'.
feats->Row(non_cached_indexes[i]).CopyFromVec(*(cache_[t]));
} else {
SubVector<BaseFloat> this_feat(non_cached_feats, i);
feats->Row(non_cached_indexes[i]).CopyFromVec(this_feat);
if (static_cast<size_t>(t) >= cache_.size())
cache_.resize(t + 1, NULL);
cache_[t] = new Vector<BaseFloat>(this_feat);
}
}
}
void OnlineCacheFeature::ClearCache() {
for (size_t i = 0; i < cache_.size(); i++)
delete cache_[i];
cache_.resize(0);
}
void OnlineAppendFeature::GetFrame(int32 frame, VectorBase<BaseFloat> *feat) {
KALDI_ASSERT(feat->Dim() == Dim());
SubVector<BaseFloat> feat1(*feat, 0, src1_->Dim());
SubVector<BaseFloat> feat2(*feat, src1_->Dim(), src2_->Dim());
src1_->GetFrame(frame, &feat1);
src2_->GetFrame(frame, &feat2);
};
} // namespace kaldi