/* * Ekiga -- A VoIP and Video-Conferencing application * Copyright (C) 2000-2009 Damien Sandras * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. This program is distributed in the hope * that it will be useful, but WITHOUT ANY WARRANTY; without even the * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. * * Ekiga is licensed under the GPL license and as a special exception, you * have permission to link or otherwise combine this program with the * programs OPAL, OpenH323 and PWLIB, and distribute the combination, without * applying the requirements of the GNU GPL to the OPAL, OpenH323 and PWLIB * programs, as long as you do follow the requirements of the GNU GPL for all * the rest of the software thus combined. */ /* * audiooutput-manager.h - description * ------------------------------------------ * begin : written in 2008 by Matthias Schneider * copyright : (c) 2008 by Matthias Schneider * description : Declaration of the interface of an audiooutput manager * implementation backend. * */ #ifndef __AUDIOOUTPUT_MANAGER_H__ #define __AUDIOOUTPUT_MANAGER_H__ #include #include #include "audiooutput-info.h" namespace Ekiga { /** * @addtogroup audiooutput * @{ */ /** Generic implementation for the Ekiga::AudioOutputManager class. * * Each AudioOutputManager will represent a specific backend able to play back audio. * Each AudioOutputManager will manage one or more devices. * The AudioOutputCore will control the different managers and their devices. */ class AudioOutputManager { public: /** The constructor */ AudioOutputManager () {} /** The destructor */ virtual ~AudioOutputManager () {} /*** API for audio output ***/ /** Get a list of all devices supported by the manager. * Add it to the list of devices already collected by the core. * @param devices a vector of device names to be filled by the manager. */ virtual void get_devices (std::vector & devices) = 0; /** Set the current device. * Must be called before opening the device. * In case a different device of the same manager was opened before, it must be * closed before setting the new device. * @param prim whether to set the primary or secondary device. * @param device the device to be used. */ virtual bool set_device (AudioOutputPS ps, const AudioOutputDevice & device) = 0; /** Open the device. * The device must be opened before calling set_frame_data(), set_buffer_size() and set_volume(). * Requires the set_device() to be called before. * Returns false if the device cannot be opened. Also sends a GUI callback to the main thread in that case. * @param prim whether the device shall be opened as primary or secondary device. * @param channels number of channels (1=mono, 2=stereo). * @param samplerate the samplerate. * @param bits_per_sample the number bits per sample. * @return true if the opening succeeded. False if the device cannot be opened. */ virtual bool open (AudioOutputPS ps, unsigned channels, unsigned samplerate, unsigned bits_per_sample) = 0; /** Close the device. */ virtual void close (AudioOutputPS /*ps*/) {}; /** Set the buffer size. * The buffer size must be set before calling set_frame_data(). * Requires the device to be opened. * @param prim whether buffers of the primary or secodnary device shall be set. * @param buffer_size the size of each buffer in bytes. * @param num_buffers the number of buffers. */ virtual void set_buffer_size (AudioOutputPS /*ps*/, unsigned /*buffer_size*/, unsigned /*num_buffers*/) {}; /** Set one audio buffer. * Requires the device to be opened and the buffer size to be set. * Returns false if writing the device fails. Also sends a GUI callback to the main thread in that case. * @param data a pointer to the buffer with the data to be written. It will not be freed. * @param size the size of the buffer to be written. * @param bytes_written returns the number of bytes actually written. Should be equal to size. * @return false if the writing failed. */ virtual bool set_frame_data (AudioOutputPS ps, const char *data, unsigned size, unsigned & bytes_written) = 0; /** Set the volume level for the current device. * Requires the device to be opened. * @param prim wether the volume of the primary or secondary device shall be set. * @param volume the new volume (0..255). */ virtual void set_volume (AudioOutputPS /*ps*/, unsigned /* volume */ ) {}; /** Returns true if a specific device is supported by the manager. * If the device specified by sink and device_name is supported by the manager, true * is returned and an AudioOutputDevice structure filled with the respective details. * @param sink the sink type of the device (e.g. alsa, oss, etc.). * @param device_name the name of the device. * @param device in case the device is supported by the manager, this structure will be filled with the device details. * @return true if the device is supported by the manager. */ virtual bool has_device (const std::string & sink, const std::string & device_name, AudioOutputDevice & device) = 0; /*** API to act on AudioOutputDevice events ***/ /** This signal is emitted when an audio output device is opened. * @param prim whether the primary or secondary audio output device was opened. * @param device the audio output device that was opened. * @param config the current audio output device configuration (current volume, etc.). */ sigc::signal3 device_opened; /** This signal is emitted when an audio output device is closed. * @param prim whether the primary or secondary audio output device was closed. * @param device the audio output device that was closed. */ sigc::signal2 device_closed; /** This signal is emitted when an error occurs when opening an audio output device. * @param prim whether the primary or secondary audio output device caused the error. * @param device the audio output device that caused the error. * @param error_code the audio output device error code. */ sigc::signal3 device_error; protected: typedef struct ManagerState { bool opened; unsigned channels; unsigned samplerate; unsigned bits_per_sample; AudioOutputDevice device; } ManagerState; ManagerState current_state[2]; }; /** * @} */ }; #endif