voice-gateway-service/pjproject/pjmedia/include/pjmedia/audiodev.h

/* 
 * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com)
 * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org>
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */
#ifndef __PJMEDIA_AUDIO_DEV_H__
#define __PJMEDIA_AUDIO_DEV_H__

/**
 * @file audiodev.h
 * @brief Audio device API.
 */
#include <pjmedia-audiodev/config.h>
#include <pjmedia-audiodev/errno.h>
#include <pjmedia/format.h>
#include <pjmedia/frame.h>
#include <pjmedia/types.h>
#include <pj/pool.h>


PJ_BEGIN_DECL

/**
 * @defgroup PJMEDIA_AUDIODEV_API Audio Device API Reference
 * @ingroup audio_device_api
 * @brief Documentation and API Reference
 * @{
 *
 * @section ec_sec Hardware/Built-in Echo Cancellation
 *
 * On some platforms, audio device comes with built-in echo cancellation
 * feature. This is usually done based on specific hardware configuration,
 * such as the use of multiple microphones and/or a known fixed distance
 * between the capture and playback device, in order to precalculate the
 * echo time distance. Because of this, when using the hardware EC,
 * users may not get the freedom to select their own audio devices.
 * This is applicable for Mac (users must use default audio devices) and
 * iOS (users must use the same built-in audio device).
 *
 * In PJMEDIA, applications wishing to use sofware echo instead can pass
 * PJMEDIA_ECHO_USE_SW_ECHO when calling pjmedia_snd_port_create2().
 */

/**
 * Type for device index.
 */
typedef pj_int32_t pjmedia_aud_dev_index;

/**
 * Device index constants.
 */

/**
 * Constant to denote default capture device
 */
#define PJMEDIA_AUD_DEFAULT_CAPTURE_DEV  -1

/**
 * Constant to denote default playback device
 */
#define PJMEDIA_AUD_DEFAULT_PLAYBACK_DEV -2

/**
 * Constant to denote invalid device index.
 */
#define PJMEDIA_AUD_INVALID_DEV     -3

#define PJMEDIA_AUD_MAX_DRIVERS 16
#define PJMEDIA_AUD_MAX_DEVS    64


/** Forward declaration for pjmedia_aud_stream */
typedef struct pjmedia_aud_stream pjmedia_aud_stream;

/** Forward declaration for audio device factory */
typedef struct pjmedia_aud_dev_factory pjmedia_aud_dev_factory;

/* typedef for factory creation function */
typedef pjmedia_aud_dev_factory*
(*pjmedia_aud_dev_factory_create_func_ptr)(pj_pool_factory*);


/* Audio driver structure */
typedef struct pjmedia_aud_driver
{
    pjmedia_aud_dev_factory_create_func_ptr create; /* Creation function    */
    pjmedia_aud_dev_factory *f;           /* Factory instance               */
    char                     name[32];    /* Driver name                    */
    unsigned                 dev_cnt;     /* Number of devices              */
    unsigned                 start_idx;   /* Start index in global list     */
    int                      rec_dev_idx; /* Default capture device.        */
    int                      play_dev_idx;/* Default playback device        */
    int                      dev_idx;     /* Default device.                */
} pjmedia_aud_driver;


/* Audio subsystem structure */
typedef struct pjmedia_aud_subsys
{
    unsigned            init_count;     /* How many times init() is called  */
    pj_pool_factory    *pf;             /* The pool factory.                */

    unsigned            drv_cnt;        /* Number of drivers.               */
    pjmedia_aud_driver  drv[PJMEDIA_AUD_MAX_DRIVERS];/* Array of drivers.   */

    unsigned            dev_cnt;        /* Total number of devices.         */
    pj_uint32_t         dev_list[PJMEDIA_AUD_MAX_DEVS];/* Array of dev IDs. */

} pjmedia_aud_subsys;


/**
 * This enumeration identifies various audio device capabilities. These audio
 * capabilities indicates what features are supported by the underlying
 * audio device implementation.
 *
 * Applications get these capabilities in the #pjmedia_aud_dev_info structure.
 *
 * Application can also set the specific features/capabilities when opening
 * the audio stream by setting the \a flags member of #pjmedia_aud_param
 * structure.
 *
 * Once audio stream is running, application can also retrieve or set some
 * specific audio capability, by using #pjmedia_aud_stream_get_cap() and
 * #pjmedia_aud_stream_set_cap() and specifying the desired capability. The
 * value of the capability is specified as pointer, and application needs to
 * supply the pointer with the correct value, according to the documentation
 * of each of the capability.
 */
typedef enum pjmedia_aud_dev_cap
{
    /** 
     * Support for audio formats other than PCM. The value of this capability
     * is represented by #pjmedia_format structure.
     */
    PJMEDIA_AUD_DEV_CAP_EXT_FORMAT = 1,

    /** 
     * Support for audio input latency control or query. The value of this 
     * capability is an unsigned integer containing milliseconds value of
     * the latency.
     */
    PJMEDIA_AUD_DEV_CAP_INPUT_LATENCY = 2,

    /** 
     * Support for audio output latency control or query. The value of this 
     * capability is an unsigned integer containing milliseconds value of
     * the latency.
     */
    PJMEDIA_AUD_DEV_CAP_OUTPUT_LATENCY = 4,

    /** 
     * Support for setting/retrieving the audio input device volume level.
     * The value of this capability is an unsigned integer representing 
     * the input audio volume setting in percent.
     */
    PJMEDIA_AUD_DEV_CAP_INPUT_VOLUME_SETTING = 8,

    /** 
     * Support for setting/retrieving the audio output device volume level.
     * The value of this capability is an unsigned integer representing 
     * the output audio volume setting in percent.
     */
    PJMEDIA_AUD_DEV_CAP_OUTPUT_VOLUME_SETTING = 16,

    /** 
     * Support for monitoring the current audio input signal volume. 
     * The value of this capability is an unsigned integer representing 
     * the audio volume in percent.
     */
    PJMEDIA_AUD_DEV_CAP_INPUT_SIGNAL_METER = 32,

    /** 
     * Support for monitoring the current audio output signal volume. 
     * The value of this capability is an unsigned integer representing 
     * the audio volume in percent.
     */
    PJMEDIA_AUD_DEV_CAP_OUTPUT_SIGNAL_METER = 64,

    /** 
     * Support for audio input routing/source. The value of this capability
     * is an integer containing #pjmedia_aud_dev_route enumeration.
     */
    PJMEDIA_AUD_DEV_CAP_INPUT_ROUTE = 128,
    PJMEDIA_AUD_DEV_CAP_INPUT_SOURCE = 128,

    /** 
     * Support for audio output routing (e.g. loudspeaker vs earpiece). The
     * value of this capability is an integer containing #pjmedia_aud_dev_route
     * enumeration.
     */
    PJMEDIA_AUD_DEV_CAP_OUTPUT_ROUTE = 256,

    /** 
     * The audio device has echo cancellation feature. The value of this
     * capability is a pj_bool_t containing boolean PJ_TRUE or PJ_FALSE.
     */
    PJMEDIA_AUD_DEV_CAP_EC = 512,

    /** 
     * The audio device supports setting echo cancellation fail length. The
     * value of this capability is an unsigned integer representing the
     * echo tail in milliseconds.
     */
    PJMEDIA_AUD_DEV_CAP_EC_TAIL = 1024,

    /** 
     * The audio device has voice activity detection feature. The value
     * of this capability is a pj_bool_t containing boolean PJ_TRUE or 
     * PJ_FALSE.
     */
    PJMEDIA_AUD_DEV_CAP_VAD = 2048,

    /** 
     * The audio device has comfort noise generation feature. The value
     * of this capability is a pj_bool_t containing boolean PJ_TRUE or 
     * PJ_FALSE.
     */
    PJMEDIA_AUD_DEV_CAP_CNG = 4096,

    /** 
     * The audio device has packet loss concealment feature. The value
     * of this capability is a pj_bool_t containing boolean PJ_TRUE or 
     * PJ_FALSE.
     */
    PJMEDIA_AUD_DEV_CAP_PLC = 8192,
    
    /**
     * End of capability
     */
    PJMEDIA_AUD_DEV_CAP_MAX = 16384

} pjmedia_aud_dev_cap;


/**
 * This enumeration describes audio routing/source setting.
 */
typedef enum pjmedia_aud_dev_route
{
    /**
     * Default route/source, it is the default audio route/source of
     * the audio framework backend, as in opening audio device without
     * specifying any route/source setting or with specifying neutral
     * route/source setting.
     */
    PJMEDIA_AUD_DEV_ROUTE_DEFAULT = 0,

    /** Route to loudspeaker */
    PJMEDIA_AUD_DEV_ROUTE_LOUDSPEAKER = 1,

    /** Route to earpiece */
    PJMEDIA_AUD_DEV_ROUTE_EARPIECE = 2,

    /** Route to paired Bluetooth device */
    PJMEDIA_AUD_DEV_ROUTE_BLUETOOTH = 4,

    /** 
     * Custom audio route/source, specific to each audio device
     * backend.
     *
     * For Android JNI audio device, the default is
     * VOICE_COMMUNICATION (7). To change it to another value, set
     * the input source capability of pjmedia_aud_param accordingly.
     * For example:
     *   // 6 is VOICE_RECOGNITION
     *   unsigned aud_source = PJMEDIA_AUD_DEV_ROUTE_CUSTOM | 6;
     *   pjmedia_aud_param_set_cap(&param, PJMEDIA_AUD_DEV_CAP_INPUT_SOURCE,
     *                             &aud_source);
     */
    PJMEDIA_AUD_DEV_ROUTE_CUSTOM = 128

} pjmedia_aud_dev_route;


/**
 * Device information structure returned by #pjmedia_aud_dev_get_info().
 */
typedef struct pjmedia_aud_dev_info
{
    /** 
     * The device ID
     */
    pjmedia_aud_dev_index id;

    /** 
     * The device name 
     */
    char name[PJMEDIA_AUD_DEV_INFO_NAME_LEN];

    /** 
     * Maximum number of input channels supported by this device. If the
     * value is zero, the device does not support input operation (i.e.
     * it is a playback only device). 
     */
    unsigned input_count;

    /** 
     * Maximum number of output channels supported by this device. If the
     * value is zero, the device does not support output operation (i.e. 
     * it is an input only device).
     */
    unsigned output_count;

    /** 
     * Default sampling rate.
     */
    unsigned default_samples_per_sec;

    /** 
     * The underlying driver name 
     */
    char driver[32];

    /** 
     * Device capabilities, as bitmask combination of #pjmedia_aud_dev_cap.
     */
    unsigned caps;

    /** 
     * Supported audio device routes/sources, as bitmask combination of 
     * #pjmedia_aud_dev_route. The value may be zero if the device
     * does not support changing audio routes/sources.
     */
    unsigned routes;

    /** 
     * Number of audio formats supported by this device. The value may be
     * zero if the device does not support non-PCM format.
     */
    unsigned ext_fmt_cnt;

    /** 
     * Array of supported extended audio formats 
     */
    pjmedia_format ext_fmt[8];


} pjmedia_aud_dev_info;


/** 
 * This callback is called by player stream when it needs additional data
 * to be played by the device. Application must fill in the whole of output 
 * buffer with audio samples.
 *
 * The frame argument contains the following values:
 *  - timestamp     Playback timestamp, in samples.
 *  - buf           Buffer to be filled out by application.
 *  - size          The size requested in bytes, which will be equal to
 *                  the size of one whole packet.
 *
 * @param user_data User data associated with the stream.
 * @param frame     Audio frame, which buffer is to be filled in by
 *                  the application.
 *
 * @return          Returning non-PJ_SUCCESS will cause the audio stream
 *                  to stop
 */
typedef pj_status_t (*pjmedia_aud_play_cb)(void *user_data,
                                           pjmedia_frame *frame);

/**
 * This callback is called by recorder stream when it has captured the whole
 * packet worth of audio samples.
 *
 * @param user_data User data associated with the stream.
 * @param frame     Captured frame.
 *
 * @return          Returning non-PJ_SUCCESS will cause the audio stream
 *                  to stop
 */
typedef pj_status_t (*pjmedia_aud_rec_cb)(void *user_data,
                                          pjmedia_frame *frame);

/**
 * This structure specifies the parameters to open the audio stream.
 */
typedef struct pjmedia_aud_param
{
    /**
     * The audio direction. This setting is mandatory.
     */
    pjmedia_dir dir;

    /**
     * The audio recorder device ID. This setting is mandatory if the audio
     * direction includes input/capture direction.
     */
    pjmedia_aud_dev_index rec_id;

    /**
     * The audio playback device ID. This setting is mandatory if the audio
     * direction includes output/playback direction.
     */
    pjmedia_aud_dev_index play_id;

    /** 
     * Clock rate/sampling rate. This setting is mandatory. 
     */
    unsigned clock_rate;

    /** 
     * Number of channels. This setting is mandatory. 
     */
    unsigned channel_count;

    /** 
     * Number of samples per frame. This setting is mandatory. 
     */
    unsigned samples_per_frame;

    /** 
     * Number of bits per sample. This setting is mandatory. 
     */
    unsigned bits_per_sample;

    /** 
     * This flags specifies which of the optional settings are valid in this
     * structure. The flags is bitmask combination of pjmedia_aud_dev_cap.
     */
    unsigned flags;

    /** 
     * Set the audio format. This setting is optional, and will only be used
     * if PJMEDIA_AUD_DEV_CAP_EXT_FORMAT is set in the flags.
     */
    pjmedia_format ext_fmt;

    /**
     * Input latency, in milliseconds. This setting is optional, and will 
     * only be used if PJMEDIA_AUD_DEV_CAP_INPUT_LATENCY is set in the flags.
     */
    unsigned input_latency_ms;

    /**
     * Input latency, in milliseconds. This setting is optional, and will 
     * only be used if PJMEDIA_AUD_DEV_CAP_OUTPUT_LATENCY is set in the flags.
     */
    unsigned output_latency_ms;

    /**
     * Input volume setting, in percent. This setting is optional, and will 
     * only be used if PJMEDIA_AUD_DEV_CAP_INPUT_VOLUME_SETTING is set in 
     * the flags.
     */
    unsigned input_vol;

    /**
     * Output volume setting, in percent. This setting is optional, and will 
     * only be used if PJMEDIA_AUD_DEV_CAP_OUTPUT_VOLUME_SETTING is set in 
     * the flags.
     */
    unsigned output_vol;

    /** 
     * Set the audio input route/source. This setting is optional, and
     * will only be used if PJMEDIA_AUD_DEV_CAP_INPUT_ROUTE/
     * PJMEDIA_AUD_DEV_CAP_INPUT_SOURCE is set in the flags.
     */
    pjmedia_aud_dev_route input_route;

    /** 
     * Set the audio output route. This setting is optional, and will only be
     * used if PJMEDIA_AUD_DEV_CAP_OUTPUT_ROUTE is set in the flags.
     */
    pjmedia_aud_dev_route output_route;

    /**
     * Enable/disable echo canceller, if the device supports it. This setting
     * is optional, and will only be used if PJMEDIA_AUD_DEV_CAP_EC is set in
     * the flags.
     */
    pj_bool_t ec_enabled;

    /**
     * Set echo canceller tail length in milliseconds, if the device supports
     * it. This setting is optional, and will only be used if
     * PJMEDIA_AUD_DEV_CAP_EC_TAIL is set in the flags.
     */
    unsigned ec_tail_ms;

    /** 
     * Enable/disable PLC. This setting is optional, and will only be used
     * if PJMEDIA_AUD_DEV_CAP_PLC is set in the flags.
     */
    pj_bool_t plc_enabled;

    /** 
     * Enable/disable CNG. This setting is optional, and will only be used
     * if PJMEDIA_AUD_DEV_CAP_CNG is set in the flags.
     */
    pj_bool_t cng_enabled;

    /** 
     * Enable/disable VAD. This setting is optional, and will only be used
     * if PJMEDIA_AUD_DEV_CAP_VAD is set in the flags.
     */
    pj_bool_t vad_enabled;

} pjmedia_aud_param;


/**
 * Get the audio subsystem.
 *
 * @return              The audio subsystem.
 */
PJ_DECL(pjmedia_aud_subsys*) pjmedia_get_aud_subsys(void);

/**
 * Initialize the audio driver.
 *
 * @param drv_idx       The index of the audio driver.
 * @param refresh       Specify non-zero to refresh the audio driver.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_driver_init(unsigned drv_idx,
                                             pj_bool_t refresh);

/**
 * Deinitialize the audio driver.
 *
 * @param drv_idx       The index of the audio driver.
 */
PJ_DECL(void) pjmedia_aud_driver_deinit(unsigned drv_idx);


/**
 * Get string info for the specified capability.
 *
 * @param cap           The capability ID.
 * @param p_desc        Optional pointer which will be filled with longer 
 *                      description about the capability.
 *
 * @return              Capability name.
 */
PJ_DECL(const char*) pjmedia_aud_dev_cap_name(pjmedia_aud_dev_cap cap,
                                              const char **p_desc);


/**
 * Set a capability field value in #pjmedia_aud_param structure. This will
 * also set the flags field for the specified capability in the structure.
 *
 * @param param         The structure.
 * @param cap           The audio capability which value is to be set.
 * @param pval          Pointer to value. Please see the type of value to
 *                      be supplied in the pjmedia_aud_dev_cap documentation.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_param_set_cap(pjmedia_aud_param *param,
                                               pjmedia_aud_dev_cap cap,
                                               const void *pval);


/**
 * Get a capability field value from #pjmedia_aud_param structure. This
 * function will return PJMEDIA_EAUD_INVCAP error if the flag for that
 * capability is not set in the flags field in the structure.
 *
 * @param param         The structure.
 * @param cap           The audio capability which value is to be retrieved.
 * @param pval          Pointer to value. Please see the type of value to
 *                      be supplied in the pjmedia_aud_dev_cap documentation.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_param_get_cap(const pjmedia_aud_param *param,
                                               pjmedia_aud_dev_cap cap,
                                               void *pval);


/**
 * Refresh the list of sound devices installed in the system. This function
 * will only refresh the list of audio device so all active audio streams will
 * be unaffected. After refreshing the device list, application MUST make sure
 * to update all index references to audio devices (i.e. all variables of type
 * pjmedia_aud_dev_index) before calling any function that accepts audio device
 * index as its parameter.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_dev_refresh(void);


/**
 * Get the number of sound devices installed in the system.
 *
 * @return              The number of sound devices installed in the system.
 */
PJ_DECL(unsigned) pjmedia_aud_dev_count(void);


/**
 * Get device information.
 *
 * @param id            The audio device ID.
 * @param info          The device information which will be filled in by this
 *                      function once it returns successfully.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_dev_get_info(pjmedia_aud_dev_index id,
                                              pjmedia_aud_dev_info *info);


/**
 * Lookup device index based on the driver and device name.
 *
 * @param drv_name      The driver name.
 * @param dev_name      The device name.
 * @param id            Pointer to store the returned device ID.
 *
 * @return              PJ_SUCCESS if the device can be found.
 */
PJ_DECL(pj_status_t) pjmedia_aud_dev_lookup(const char *drv_name,
                                            const char *dev_name,
                                            pjmedia_aud_dev_index *id);


/**
 * Initialize the audio device parameters with default values for the
 * specified device.
 *
 * @param id            The audio device ID.
 * @param param         The audio device parameters which will be initialized
 *                      by this function once it returns successfully.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_dev_default_param(pjmedia_aud_dev_index id,
                                                   pjmedia_aud_param *param);


/**
 * Open audio stream object using the specified parameters.
 *
 * @param param         Sound device parameters to be used for the stream.
 * @param rec_cb        Callback to be called on every input frame captured.
 * @param play_cb       Callback to be called everytime the sound device needs
 *                      audio frames to be played back.
 * @param user_data     Arbitrary user data, which will be given back in the
 *                      callbacks.
 * @param p_strm        Pointer to receive the audio stream.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_create(const pjmedia_aud_param *param,
                                               pjmedia_aud_rec_cb rec_cb,
                                               pjmedia_aud_play_cb play_cb,
                                               void *user_data,
                                               pjmedia_aud_stream **p_strm);

/**
 * Get the running parameters for the specified audio stream.
 *
 * @param strm          The audio stream.
 * @param param         Audio stream parameters to be filled in by this 
 *                      function once it returns successfully.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_get_param(pjmedia_aud_stream *strm,
                                                  pjmedia_aud_param *param);

/**
 * Get the value of a specific capability of the audio stream.
 *
 * @param strm          The audio stream.
 * @param cap           The audio capability which value is to be retrieved.
 * @param value         Pointer to value to be filled in by this function 
 *                      once it returns successfully.  Please see the type 
 *                      of value to be supplied in the pjmedia_aud_dev_cap
 *                      documentation.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_get_cap(pjmedia_aud_stream *strm,
                                                pjmedia_aud_dev_cap cap,
                                                void *value);

/**
 * Set the value of a specific capability of the audio stream.
 *
 * @param strm          The audio stream.
 * @param cap           The audio capability which value is to be set.
 * @param value         Pointer to value. Please see the type of value to
 *                      be supplied in the pjmedia_aud_dev_cap documentation.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_set_cap(pjmedia_aud_stream *strm,
                                                pjmedia_aud_dev_cap cap,
                                                const void *value);

/**
 * Start the stream.
 *
 * @param strm          The audio stream.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_start(pjmedia_aud_stream *strm);

/**
 * Stop the stream.
 *
 * @param strm          The audio stream.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_stop(pjmedia_aud_stream *strm);

/**
 * Destroy the stream.
 *
 * @param strm          The audio stream.
 *
 * @return              PJ_SUCCESS on successful operation or the appropriate
 *                      error code.
 */
PJ_DECL(pj_status_t) pjmedia_aud_stream_destroy(pjmedia_aud_stream *strm);


/**
 * @}
 */

PJ_END_DECL


#endif  /* __PJMEDIA_AUDIO_DEV_H__ */