tetris/SFML-2.4.2/include/SFML/Audio/SoundRecorder.hpp
2018-02-06 01:44:42 +02:00

409 lines
15 KiB
C++

////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2017 Laurent Gomila (laurent@sfml-dev.org)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
// you must not claim that you wrote the original software.
// If you use this software in a product, an acknowledgment
// in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
// and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////
#ifndef SFML_SOUNDRECORDER_HPP
#define SFML_SOUNDRECORDER_HPP
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Audio/Export.hpp>
#include <SFML/Audio/AlResource.hpp>
#include <SFML/System/Thread.hpp>
#include <SFML/System/Time.hpp>
#include <vector>
#include <string>
namespace sf
{
////////////////////////////////////////////////////////////
/// \brief Abstract base class for capturing sound data
///
////////////////////////////////////////////////////////////
class SFML_AUDIO_API SoundRecorder : AlResource
{
public:
////////////////////////////////////////////////////////////
/// \brief destructor
///
////////////////////////////////////////////////////////////
virtual ~SoundRecorder();
////////////////////////////////////////////////////////////
/// \brief Start the capture
///
/// The \a sampleRate parameter defines the number of audio samples
/// captured per second. The higher, the better the quality
/// (for example, 44100 samples/sec is CD quality).
/// This function uses its own thread so that it doesn't block
/// the rest of the program while the capture runs.
/// Please note that only one capture can happen at the same time.
/// You can select which capture device will be used, by passing
/// the name to the setDevice() method. If none was selected
/// before, the default capture device will be used. You can get a
/// list of the names of all available capture devices by calling
/// getAvailableDevices().
///
/// \param sampleRate Desired capture rate, in number of samples per second
///
/// \return True, if start of capture was successful
///
/// \see stop, getAvailableDevices
///
////////////////////////////////////////////////////////////
bool start(unsigned int sampleRate = 44100);
////////////////////////////////////////////////////////////
/// \brief Stop the capture
///
/// \see start
///
////////////////////////////////////////////////////////////
void stop();
////////////////////////////////////////////////////////////
/// \brief Get the sample rate
///
/// The sample rate defines the number of audio samples
/// captured per second. The higher, the better the quality
/// (for example, 44100 samples/sec is CD quality).
///
/// \return Sample rate, in samples per second
///
////////////////////////////////////////////////////////////
unsigned int getSampleRate() const;
////////////////////////////////////////////////////////////
/// \brief Get a list of the names of all available audio capture devices
///
/// This function returns a vector of strings, containing
/// the names of all available audio capture devices.
///
/// \return A vector of strings containing the names
///
////////////////////////////////////////////////////////////
static std::vector<std::string> getAvailableDevices();
////////////////////////////////////////////////////////////
/// \brief Get the name of the default audio capture device
///
/// This function returns the name of the default audio
/// capture device. If none is available, an empty string
/// is returned.
///
/// \return The name of the default audio capture device
///
////////////////////////////////////////////////////////////
static std::string getDefaultDevice();
////////////////////////////////////////////////////////////
/// \brief Set the audio capture device
///
/// This function sets the audio capture device to the device
/// with the given \a name. It can be called on the fly (i.e:
/// while recording). If you do so while recording and
/// opening the device fails, it stops the recording.
///
/// \param name The name of the audio capture device
///
/// \return True, if it was able to set the requested device
///
/// \see getAvailableDevices, getDefaultDevice
///
////////////////////////////////////////////////////////////
bool setDevice(const std::string& name);
////////////////////////////////////////////////////////////
/// \brief Get the name of the current audio capture device
///
/// \return The name of the current audio capture device
///
////////////////////////////////////////////////////////////
const std::string& getDevice() const;
////////////////////////////////////////////////////////////
/// \brief Set the channel count of the audio capture device
///
/// This method allows you to specify the number of channels
/// used for recording. Currently only 16-bit mono and
/// 16-bit stereo are supported.
///
/// \param channelCount Number of channels. Currently only
/// mono (1) and stereo (2) are supported.
///
/// \see getChannelCount
///
////////////////////////////////////////////////////////////
void setChannelCount(unsigned int channelCount);
////////////////////////////////////////////////////////////
/// \brief Get the number of channels used by this recorder
///
/// Currently only mono and stereo are supported, so the
/// value is either 1 (for mono) or 2 (for stereo).
///
/// \return Number of channels
///
/// \see setChannelCount
///
////////////////////////////////////////////////////////////
unsigned int getChannelCount() const;
////////////////////////////////////////////////////////////
/// \brief Check if the system supports audio capture
///
/// This function should always be called before using
/// the audio capture features. If it returns false, then
/// any attempt to use sf::SoundRecorder or one of its derived
/// classes will fail.
///
/// \return True if audio capture is supported, false otherwise
///
////////////////////////////////////////////////////////////
static bool isAvailable();
protected:
////////////////////////////////////////////////////////////
/// \brief Default constructor
///
/// This constructor is only meant to be called by derived classes.
///
////////////////////////////////////////////////////////////
SoundRecorder();
////////////////////////////////////////////////////////////
/// \brief Set the processing interval
///
/// The processing interval controls the period
/// between calls to the onProcessSamples function. You may
/// want to use a small interval if you want to process the
/// recorded data in real time, for example.
///
/// Note: this is only a hint, the actual period may vary.
/// So don't rely on this parameter to implement precise timing.
///
/// The default processing interval is 100 ms.
///
/// \param interval Processing interval
///
////////////////////////////////////////////////////////////
void setProcessingInterval(Time interval);
////////////////////////////////////////////////////////////
/// \brief Start capturing audio data
///
/// This virtual function may be overridden by a derived class
/// if something has to be done every time a new capture
/// starts. If not, this function can be ignored; the default
/// implementation does nothing.
///
/// \return True to start the capture, or false to abort it
///
////////////////////////////////////////////////////////////
virtual bool onStart();
////////////////////////////////////////////////////////////
/// \brief Process a new chunk of recorded samples
///
/// This virtual function is called every time a new chunk of
/// recorded data is available. The derived class can then do
/// whatever it wants with it (storing it, playing it, sending
/// it over the network, etc.).
///
/// \param samples Pointer to the new chunk of recorded samples
/// \param sampleCount Number of samples pointed by \a samples
///
/// \return True to continue the capture, or false to stop it
///
////////////////////////////////////////////////////////////
virtual bool onProcessSamples(const Int16* samples, std::size_t sampleCount) = 0;
////////////////////////////////////////////////////////////
/// \brief Stop capturing audio data
///
/// This virtual function may be overridden by a derived class
/// if something has to be done every time the capture
/// ends. If not, this function can be ignored; the default
/// implementation does nothing.
///
////////////////////////////////////////////////////////////
virtual void onStop();
private:
////////////////////////////////////////////////////////////
/// \brief Function called as the entry point of the thread
///
/// This function starts the recording loop, and returns
/// only when the capture is stopped.
///
////////////////////////////////////////////////////////////
void record();
////////////////////////////////////////////////////////////
/// \brief Get the new available audio samples and process them
///
/// This function is called continuously during the
/// capture loop. It retrieves the captured samples and
/// forwards them to the derived class.
///
////////////////////////////////////////////////////////////
void processCapturedSamples();
////////////////////////////////////////////////////////////
/// \brief Clean up the recorder's internal resources
///
/// This function is called when the capture stops.
///
////////////////////////////////////////////////////////////
void cleanup();
////////////////////////////////////////////////////////////
// Member data
////////////////////////////////////////////////////////////
Thread m_thread; ///< Thread running the background recording task
std::vector<Int16> m_samples; ///< Buffer to store captured samples
unsigned int m_sampleRate; ///< Sample rate
Time m_processingInterval; ///< Time period between calls to onProcessSamples
bool m_isCapturing; ///< Capturing state
std::string m_deviceName; ///< Name of the audio capture device
unsigned int m_channelCount; ///< Number of recording channels
};
} // namespace sf
#endif // SFML_SOUNDRECORDER_HPP
////////////////////////////////////////////////////////////
/// \class sf::SoundRecorder
/// \ingroup audio
///
/// sf::SoundBuffer provides a simple interface to access
/// the audio recording capabilities of the computer
/// (the microphone). As an abstract base class, it only cares
/// about capturing sound samples, the task of making something
/// useful with them is left to the derived class. Note that
/// SFML provides a built-in specialization for saving the
/// captured data to a sound buffer (see sf::SoundBufferRecorder).
///
/// A derived class has only one virtual function to override:
/// \li onProcessSamples provides the new chunks of audio samples while the capture happens
///
/// Moreover, two additional virtual functions can be overridden
/// as well if necessary:
/// \li onStart is called before the capture happens, to perform custom initializations
/// \li onStop is called after the capture ends, to perform custom cleanup
///
/// A derived class can also control the frequency of the onProcessSamples
/// calls, with the setProcessingInterval protected function. The default
/// interval is chosen so that recording thread doesn't consume too much
/// CPU, but it can be changed to a smaller value if you need to process
/// the recorded data in real time, for example.
///
/// The audio capture feature may not be supported or activated
/// on every platform, thus it is recommended to check its
/// availability with the isAvailable() function. If it returns
/// false, then any attempt to use an audio recorder will fail.
///
/// If you have multiple sound input devices connected to your
/// computer (for example: microphone, external soundcard, webcam mic, ...)
/// you can get a list of all available devices through the
/// getAvailableDevices() function. You can then select a device
/// by calling setDevice() with the appropriate device. Otherwise
/// the default capturing device will be used.
///
/// By default the recording is in 16-bit mono. Using the
/// setChannelCount method you can change the number of channels
/// used by the audio capture device to record. Note that you
/// have to decide whether you want to record in mono or stereo
/// before starting the recording.
///
/// It is important to note that the audio capture happens in a
/// separate thread, so that it doesn't block the rest of the
/// program. In particular, the onProcessSamples virtual function
/// (but not onStart and not onStop) will be called
/// from this separate thread. It is important to keep this in
/// mind, because you may have to take care of synchronization
/// issues if you share data between threads.
/// Another thing to bear in mind is that you must call stop()
/// in the destructor of your derived class, so that the recording
/// thread finishes before your object is destroyed.
///
/// Usage example:
/// \code
/// class CustomRecorder : public sf::SoundRecorder
/// {
/// ~CustomRecorder()
/// {
/// // Make sure to stop the recording thread
/// stop();
/// }
///
/// virtual bool onStart() // optional
/// {
/// // Initialize whatever has to be done before the capture starts
/// ...
///
/// // Return true to start playing
/// return true;
/// }
///
/// virtual bool onProcessSamples(const Int16* samples, std::size_t sampleCount)
/// {
/// // Do something with the new chunk of samples (store them, send them, ...)
/// ...
///
/// // Return true to continue playing
/// return true;
/// }
///
/// virtual void onStop() // optional
/// {
/// // Clean up whatever has to be done after the capture ends
/// ...
/// }
/// }
///
/// // Usage
/// if (CustomRecorder::isAvailable())
/// {
/// CustomRecorder recorder;
///
/// if (!recorder.start())
/// return -1;
///
/// ...
/// recorder.stop();
/// }
/// \endcode
///
/// \see sf::SoundBufferRecorder
///
////////////////////////////////////////////////////////////