Aegisub/src/audio_controller.h

192 lines
7.2 KiB
C++

// Copyright (c) 2009-2010, Niels Martin Hansen
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// Aegisub Project http://www.aegisub.org/
#include <libaegisub/exception.h>
#include <libaegisub/signal.h>
#include <cstdint>
#include <wx/event.h>
#include <wx/power.h>
#include <wx/timer.h>
class AudioPlayer;
class AudioTimingController;
class TimeRange;
namespace agi { class AudioProvider; }
namespace agi { struct Context; }
/// @class AudioController
/// @brief Manage playback of an open audio stream
///
/// AudioController owns an AudioPlayer and uses it to play audio from the
/// project's current audio provider.
class AudioController final : public wxEvtHandler {
/// Project context this controller belongs to
agi::Context *context;
/// Slot for subtitles save signal
agi::signal::Connection subtitle_save_slot;
/// Playback is in progress and the current position was updated
agi::signal::Signal<int> AnnouncePlaybackPosition;
/// Playback has stopped
agi::signal::Signal<> AnnouncePlaybackStop;
/// The timing controller was replaced
agi::signal::Signal<> AnnounceTimingControllerChanged;
/// A new audio player was created
agi::signal::Signal<> AnnounceAudioPlayerOpened;
/// The audio output object
std::unique_ptr<AudioPlayer> player;
/// The current timing mode, if any; owned by the audio controller
std::unique_ptr<AudioTimingController> timing_controller;
enum PlaybackMode {
PM_NotPlaying,
PM_Range,
PM_PrimaryRange,
PM_ToEnd
};
/// The current playback mode
PlaybackMode playback_mode = PM_NotPlaying;
/// Timer used for playback position updates
wxTimer playback_timer;
/// The audio provider
agi::AudioProvider *provider = nullptr;
agi::signal::Connection provider_connection;
void OnAudioProvider(agi::AudioProvider *new_provider);
/// Event handler for the playback timer
void OnPlaybackTimer(wxTimerEvent &event);
/// @brief Timing controller signals primary playback range changed
void OnTimingControllerUpdatedPrimaryRange();
/// @brief Timing controller signals that the rendering style ranges have changed
void OnTimingControllerUpdatedStyleRanges();
/// Handler for the current audio player changing
void OnAudioPlayerChanged();
#ifdef wxHAS_POWER_EVENTS
/// Handle computer going into suspend mode by stopping audio and closing device
void OnComputerSuspending(wxPowerEvent &event);
/// Handle computer resuming from suspend by re-opening the audio device
void OnComputerResuming(wxPowerEvent &event);
#endif
/// @brief Convert a count of audio samples to a time in milliseconds
/// @param samples Sample count to convert
/// @return The number of milliseconds equivalent to the sample-count, rounded down
int64_t MillisecondsFromSamples(int64_t samples) const;
/// @brief Convert a time in milliseconds to a count of audio samples
/// @param ms Time in milliseconds to convert
/// @return The index of the first sample that is wholly inside the millisecond
int64_t SamplesFromMilliseconds(int64_t ms) const;
/// Get the duration of the currently open audio in milliseconds, or 0 if none
/// @return Duration in milliseconds
int GetDuration() const;
public:
AudioController(agi::Context *context);
~AudioController();
/// @brief Start or restart audio playback, playing a range
/// @param range The range of audio to play back
///
/// The end of the played back range may be requested changed, but is not
/// changed automatically from any other operations.
void PlayRange(const TimeRange &range);
/// @brief Start or restart audio playback, playing the primary playback range
///
/// If the primary playback range is updated during playback, the end of
/// the active playback range will be updated to match the new selection.
/// The playback end can not be changed in any other way.
void PlayPrimaryRange();
/// @brief Start or restart audio playback, playing from a point to the end of of the primary playback range
/// @param start_ms Time in milliseconds to start playback at
///
/// This behaves like PlayPrimaryRange, but the start point can differ from
/// the beginning of the primary range.
void PlayToEndOfPrimary(int start_ms);
/// @brief Start or restart audio playback, playing from a point to the end of stream
/// @param start_ms Time in milliseconds to start playback at
///
/// Playback to end cannot be converted to a range playback like range
/// playback can, it will continue until the end is reached, it is stopped,
/// or restarted.
void PlayToEnd(int start_ms);
/// @brief Stop all audio playback
void Stop();
/// @brief Determine whether playback is ongoing
/// @return True if audio is being played back
bool IsPlaying();
/// @brief Get the current playback position
/// @return Approximate current time in milliseconds being heard by the user
///
/// Returns 0 if playback is stopped. The return value is only approximate.
int GetPlaybackPosition();
/// @brief Get the primary playback range
/// @return An immutable TimeRange object
TimeRange GetPrimaryPlaybackRange() const;
/// @brief Set the playback audio volume
/// @param volume The new amplification factor for the audio
void SetVolume(double volume);
/// @brief Return the current timing controller
/// @return The current timing controller or 0
AudioTimingController *GetTimingController() const { return timing_controller.get(); }
/// @brief Change the current timing controller
/// @param new_mode The new timing controller or nullptr
void SetTimingController(std::unique_ptr<AudioTimingController> new_controller);
DEFINE_SIGNAL_ADDERS(AnnouncePlaybackPosition, AddPlaybackPositionListener)
DEFINE_SIGNAL_ADDERS(AnnouncePlaybackStop, AddPlaybackStopListener)
DEFINE_SIGNAL_ADDERS(AnnounceTimingControllerChanged, AddTimingControllerListener)
DEFINE_SIGNAL_ADDERS(AnnounceAudioPlayerOpened, AddAudioPlayerOpenListener)
};