resampler.h

// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// Implementation of TtsDataReceiver that resamples the audio to a
// different sample rate and then passes the resampled audio through
// to another callback.

#ifndef SPEECH_CLIENT_SYNTHESIS_SERVICE_RESAMPLER_H_
#define SPEECH_CLIENT_SYNTHESIS_SERVICE_RESAMPLER_H_

#include <stdint.h>
#include <vector>

#include "base/basictypes.h"
#include "base/compiler_specific.h"

#include "tts_receiver.h"

namespace speech_synthesis {

class Resampler : public TtsDataReceiver {
 public:
  // Resamples the audio passed to this object's Receive method and passes
  // the resampled audio through to the destination.
  Resampler(TtsDataReceiver *destination,
            int source_rate,
            int dest_rate,
            int buffer_size);

  virtual ~Resampler();

  // TtsDataReceiver override.
  virtual tts_callback_status Receive(int rate,
                                      int num_channels,
                                      const int16_t* data,
                                      int num_samples,
                                      tts_synth_status status) OVERRIDE;

  int source_rate() { return source_rate_; }

  int dest_rate() { return dest_rate_; }

 private:
  TtsDataReceiver* destination_;
  int source_rate_;
  int dest_rate_;
  double factor_;
  int buffer_size_;
  void* resample_handle_;
  std::vector<float> in_floats_;
  std::vector<float> out_floats_;
  std::vector<int16_t> out_int16s_;

  DISALLOW_COPY_AND_ASSIGN(Resampler);
};
}  // namespace speech_synthesis

#endif  // SPEECH_CLIENT_SYNTHESIS_SERVICE_RESAMPLER_H_