pcm_decoder.h

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/*
 * Copyright (c) 2015 Roc Streaming authors
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */
 
//! @file roc_audio/pcm_decoder.h
//! @brief PCM decoder.
 
#ifndef ROC_AUDIO_PCM_DECODER_H_
#define ROC_AUDIO_PCM_DECODER_H_
 
#include "roc_audio/iframe_decoder.h"
#include "roc_audio/pcm_mapper.h"
#include "roc_audio/sample_spec.h"
#include "roc_core/noncopyable.h"
 
namespace roc {
namespace audio {
 
//! PCM decoder.
class PcmDecoder : public IFrameDecoder, public core::NonCopyable<> {
public:
    //! Construction function.
    static IFrameDecoder* construct(core::IArena& arena,
                                    const PcmFormat& pcm_format,
                                    const SampleSpec& sample_spec);
 
    //! Initialize.
    PcmDecoder(const PcmFormat& pcm_format, const SampleSpec& sample_spec);
 
    //! Get current stream position.
    virtual packet::stream_timestamp_t position() const;
 
    //! Get number of samples available for decoding.
    virtual packet::stream_timestamp_t available() const;
 
    //! Get number of samples per channel, that can be decoded from given frame.
    virtual size_t decoded_sample_count(const void* frame_data, size_t frame_size) const;
 
    //! Start decoding a new frame.
    virtual void begin(packet::stream_timestamp_t frame_position,
                       const void* frame_data,
                       size_t frame_size);
 
    //! Read samples from current frame.
    virtual size_t read(sample_t* samples, size_t n_samples);
 
    //! Shift samples from current frame.
    virtual size_t shift(size_t n_samples);
 
    //! Finish decoding current frame.
    virtual void end();
 
private:
    PcmMapper pcm_mapper_;
    const size_t n_chans_;
 
    packet::stream_timestamp_t stream_pos_;
    packet::stream_timestamp_t stream_avail_;
 
    const void* frame_data_;
    size_t frame_byte_size_;
    size_t frame_bit_off_;
};
 
} // namespace audio
} // namespace roc
 
#endif // ROC_AUDIO_PCM_DECODER_H_