blob: 35783b64f2b4f9f0ebac299f8027c5fb3a7d026e [file] [log] [blame]
/*
* Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef COMMON_AUDIO_RESAMPLER_INCLUDE_PUSH_RESAMPLER_H_
#define COMMON_AUDIO_RESAMPLER_INCLUDE_PUSH_RESAMPLER_H_
#include <memory>
#include <vector>
#include "api/array_view.h"
namespace webrtc {
class PushSincResampler;
// Wraps PushSincResampler to provide stereo support.
// Note: This implementation assumes 10ms buffer sizes throughout.
// TODO(ajm): add support for an arbitrary number of channels.
template <typename T>
class PushResampler {
public:
PushResampler();
virtual ~PushResampler();
// Must be called whenever the parameters change. Free to be called at any
// time as it is a no-op if parameters have not changed since the last call.
int InitializeIfNeeded(int src_sample_rate_hz,
int dst_sample_rate_hz,
size_t num_channels);
// Returns the total number of samples provided in destination (e.g. 32 kHz,
// 2 channel audio gives 640 samples).
int Resample(rtc::ArrayView<const T> src, rtc::ArrayView<T> dst);
private:
int src_sample_rate_hz_;
int dst_sample_rate_hz_;
size_t num_channels_;
// Vector that is needed to provide the proper inputs and outputs to the
// interleave/de-interleave methods used in Resample. This needs to be
// heap-allocated on the state to support an arbitrary number of channels
// without doing run-time heap-allocations in the Resample method.
std::vector<T*> channel_data_array_;
struct ChannelResampler {
std::unique_ptr<PushSincResampler> resampler;
std::vector<T> source;
std::vector<T> destination;
};
std::vector<ChannelResampler> channel_resamplers_;
};
} // namespace webrtc
#endif // COMMON_AUDIO_RESAMPLER_INCLUDE_PUSH_RESAMPLER_H_