OnlineFeatureMatrix Class Reference

#include <online-feat-input.h>

Collaboration diagram for OnlineFeatureMatrix:

Public Member Functions
	OnlineFeatureMatrix (const OnlineFeatureMatrixOptions &opts, OnlineFeatInputItf *input)
bool	IsValidFrame (int32 frame)
int32	Dim () const
SubVector< BaseFloat >	GetFrame (int32 frame)

Private Member Functions
void	GetNextFeatures ()

Private Attributes
const OnlineFeatureMatrixOptions	opts_
OnlineFeatInputItf *	input_
int32	feat_dim_
Matrix< BaseFloat >	feat_matrix_
int32	feat_offset_
bool	finished_

Detailed Description

Definition at line 370 of file online-feat-input.h.

Constructor & Destructor Documentation

OnlineFeatureMatrix()

OnlineFeatureMatrix ( const OnlineFeatureMatrixOptions &  opts, OnlineFeatInputItf *  input  )

inline

Definition at line 372 of file online-feat-input.h.

                                                :
      opts_(opts), input_(input), feat_dim_(input->Dim()),
      feat_offset_(0), finished_(false) { }

Member Function Documentation

Dim()

int32 Dim ( ) const

inline

Definition at line 379 of file online-feat-input.h.

{ return feat_dim_; }

GetFrame()

SubVector< BaseFloat > GetFrame

(

int32

frame

)

Definition at line 539 of file online-feat-input.cc.

References KALDI_ERR.

Referenced by OnlineDecodableDiagGmmScaled::CacheFrame(), and kaldi::TestOnlineFeatureMatrix().

                                                              {
  if (frame < feat_offset_)
    KALDI_ERR << "Attempting to get a discarded frame.";
  if (frame >= feat_offset_ + feat_matrix_.NumRows())
    KALDI_ERR << "Attempt get frame without check its validity.";
  return feat_matrix_.Row(frame - feat_offset_);
}

GetNextFeatures()

void GetNextFeatures ( )

private

Definition at line 474 of file online-feat-input.cc.

References OnlineFeatInputItf::Compute(), OnlineDeltaInput::input_, KALDI_WARN, kaldi::kUndefined, MatrixBase< Real >::NumRows(), and OnlineDeltaInput::opts_.

                                          {
  if (finished_) return; // Nothing to do.

  // We always keep the most recent frame of features, if present,
  // in case it is needed (this may happen when someone calls
  // IsLastFrame(), which requires us to get the next frame, while
  // they're still processing this frame.
  bool have_last_frame = (feat_matrix_.NumRows() != 0);
  Vector<BaseFloat> last_frame;
  if (have_last_frame)
    last_frame = feat_matrix_.Row(feat_matrix_.NumRows() - 1);

  int32 iter;
  for (iter = 0; iter < opts_.num_tries; iter++) {
    Matrix<BaseFloat> next_features(opts_.batch_size, feat_dim_);
    finished_ = ! input_->Compute(&next_features);
    if (next_features.NumRows() == 0 && ! finished_) {
      // It timed out.  Try again.
      continue;
    }
    if (next_features.NumRows() > 0) {
      int32 new_size = (have_last_frame ? 1 : 0) +
          next_features.NumRows();
      feat_offset_ += feat_matrix_.NumRows() -
          (have_last_frame ? 1 : 0); // we're discarding this many
                                     // frames.
      feat_matrix_.Resize(new_size, feat_dim_, kUndefined);
      if (have_last_frame) {
        feat_matrix_.Row(0).CopyFromVec(last_frame);
        feat_matrix_.Range(1, next_features.NumRows(), 0, feat_dim_).
            CopyFromMat(next_features);
      } else {
        feat_matrix_.CopyFromMat(next_features);
      }
    }
    break;
  }
  if (iter == opts_.num_tries) { // we fell off the loop
    KALDI_WARN << "After " << opts_.num_tries << ", got no features, giving up.";
    finished_ = true; // We set finished_ to true even though the stream
    // doesn't say it's finished, because the delay is too much-- we gave up.
  }
}

IsValidFrame()

bool IsValidFrame

(

int32

frame

)

Definition at line 519 of file online-feat-input.cc.

References KALDI_ASSERT, and KALDI_WARN.

Referenced by OnlineDecodableDiagGmmScaled::CacheFrame(), OnlineDecodableDiagGmmScaled::IsLastFrame(), OnlineDecodableDiagGmmScaled::OnlineDecodableDiagGmmScaled(), and kaldi::TestOnlineFeatureMatrix().

                                                   {
   KALDI_ASSERT(frame >= feat_offset_ &&
               "You are attempting to get expired frames.");
  if (frame < feat_offset_ + feat_matrix_.NumRows())
    return true;
  else {
    GetNextFeatures();
    if (frame < feat_offset_ + feat_matrix_.NumRows())
      return true;
    else {
      if (finished_) return false;
      else {
        KALDI_WARN << "Unexpected point reached in code: "
                   << "possibly you are skipping frames?";
        return false;
      }
    }
  }
}

Member Data Documentation

feat_dim_

int32 feat_dim_

private

Definition at line 392 of file online-feat-input.h.

feat_matrix_

Matrix<BaseFloat> feat_matrix_

private

Definition at line 393 of file online-feat-input.h.

feat_offset_

int32 feat_offset_

private

Definition at line 394 of file online-feat-input.h.

finished_

bool finished_

private

Definition at line 395 of file online-feat-input.h.

input_

OnlineFeatInputItf* input_

private

Definition at line 391 of file online-feat-input.h.

opts_

const OnlineFeatureMatrixOptions opts_

private

Definition at line 390 of file online-feat-input.h.

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The documentation for this class was generated from the following files:

• online/online-feat-input.h
• online/online-feat-input.cc