Tizen Native API  5.5

The Audio Input API provides a set of functions to directly manage the system audio input devices.

Required Header

#include <audio_io.h>

Overview

The Audio Input API provides a set of functions to record audio data (PCM format) from audio devices.

Related Features

This API is related with the following features:

It is recommended to design feature related codes in your application for reliability.

You can check if a device supports the related features for this API by using System Information, thereby controlling the procedure of your application.

To ensure your application is only running on the device with specific features, please define the features in your manifest file using the manifest editor in the SDK.

More details on featuring your application can be found from Feature Element.

Functions

int audio_in_create (int sample_rate, audio_channel_e channel, audio_sample_type_e type, audio_in_h *input)
 Creates an audio device instance and returns an input handle to record PCM (pulse-code modulation) data.
int audio_in_destroy (audio_in_h input)
 Releases the audio input handle and all its resources associated with an audio stream.
int audio_in_set_sound_stream_info (audio_in_h input, sound_stream_info_h stream_info)
 Sets the sound stream information to the audio input.
int audio_in_prepare (audio_in_h input)
 Prepares the audio input for reading audio data by starting buffering of audio data from the device.
int audio_in_unprepare (audio_in_h input)
 Unprepares the audio input.
int audio_in_pause (audio_in_h input)
 Pauses buffering of audio data from the device.
int audio_in_resume (audio_in_h input)
 Resumes buffering audio data from the device.
int audio_in_flush (audio_in_h input)
 Flushes and discards buffered audio data from the input stream.
int audio_in_read (audio_in_h input, void *buffer, unsigned int length)
 Reads audio data from the audio input buffer.
int audio_in_get_buffer_size (audio_in_h input, int *size)
 Gets the size to be allocated for the audio input buffer.
int audio_in_get_sample_rate (audio_in_h input, int *sample_rate)
 Gets the sample rate of the audio input data stream.
int audio_in_get_channel (audio_in_h input, audio_channel_e *channel)
 Gets the channel type of the audio input data stream.
int audio_in_get_sample_type (audio_in_h input, audio_sample_type_e *type)
 Gets the sample audio format of the audio input data stream.
int audio_in_set_stream_cb (audio_in_h input, audio_in_stream_cb callback, void *user_data)
 Sets an asynchronous (event) callback function to handle recording PCM (pulse-code modulation) data.
int audio_in_unset_stream_cb (audio_in_h input)
 Unregisters the callback function.
int audio_in_peek (audio_in_h input, const void **buffer, unsigned int *length)
 Peeks into the 'audio in' buffer.
int audio_in_drop (audio_in_h input)
 Drops the 'audio in' buffer that was peeked into.
int audio_in_set_state_changed_cb (audio_in_h input, audio_in_state_changed_cb callback, void *user_data)
 Sets the state changed callback function to the audio input handle.
int audio_in_unset_state_changed_cb (audio_in_h input)
 Unregisters the state changed callback function of the audio input handle.

Typedefs

typedef struct audio_io_s * audio_in_h
 The audio input handle.
typedef void(* audio_in_stream_cb )(audio_in_h handle, size_t nbytes, void *user_data)
 Called when audio input data is available in asynchronous (event) mode.
typedef void(* audio_in_state_changed_cb )(audio_in_h handle, audio_io_state_e previous, audio_io_state_e current, bool by_policy, void *user_data)
 Called when the state of audio input is changed.

Typedef Documentation

typedef struct audio_io_s* audio_in_h

The audio input handle.

Since :
2.3.1
typedef void(* audio_in_state_changed_cb)(audio_in_h handle, audio_io_state_e previous, audio_io_state_e current, bool by_policy, void *user_data)

Called when the state of audio input is changed.

Since :
3.0
Parameters:
[in]handleThe handle of the audio input
[in]previousThe previous state of the audio input
[in]currentThe current state of the audio input
[in]by_policytrue if the state is changed by policy, otherwise false if the state is not changed by policy
[in]user_dataThe user data passed from the callback registration function
See also:
audio_in_set_state_changed_cb()
audio_in_unset_state_changed_cb()
typedef void(* audio_in_stream_cb)(audio_in_h handle, size_t nbytes, void *user_data)

Called when audio input data is available in asynchronous (event) mode.

Since :
2.3.1
Remarks:
Use audio_in_peek() to get 'audio in' data inside callback, use audio_in_drop() after use of peeked data.
Parameters:
[in]handleThe handle to the audio input
[in]nbytesThe amount of available 'audio in' data which can be peeked.
[in]user_dataThe user data passed from the callback registration function
See also:
audio_in_set_stream_cb()

Function Documentation

int audio_in_create ( int  sample_rate,
audio_channel_e  channel,
audio_sample_type_e  type,
audio_in_h input 
)

Creates an audio device instance and returns an input handle to record PCM (pulse-code modulation) data.

This function is used for audio input initialization.

Since :
2.3.1
Privilege Level:
public
Privilege:
http://tizen.org/privilege/recorder
Remarks:
input must be released using audio_in_destroy(). If the channel count of the requested channel is different from the system's supported channel count, then channel remapping will be processed internally.
Parameters:
[in]sample_rateThe audio sample rate
Before 5.0: 8000[Hz] ~ 48000[Hz]
Since 5.0: 8000[Hz] ~ 192000[Hz]
[in]channelThe audio channel type
Before 5.5: Mono or stereo
Since 5.5: Mono, stereo or multi-channels
[in]typeThe type of audio sample
Before 5.0: 8 or 16-bit
Since 5.0: 8, 16 or 24-bit
Since 5.5: 8, 16, 24 or 32-bit
[out]inputAn audio input handle is created on success
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_PERMISSION_DENIEDPermission denied
AUDIO_IO_ERROR_OUT_OF_MEMORYOut of memory
AUDIO_IO_ERROR_DEVICE_NOT_OPENEDDevice not opened
AUDIO_IO_ERROR_SOUND_POLICYSound policy error
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
Postcondition:
The state will be AUDIO_IO_STATE_IDLE.
audio_in_set_sound_stream_info() is recommended to be called after this API.
See also:
audio_in_destroy()
int audio_in_destroy ( audio_in_h  input)

Releases the audio input handle and all its resources associated with an audio stream.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input to destroy
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_DEVICE_NOT_CLOSEDDevice not closed
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
See also:
audio_in_create()
int audio_in_drop ( audio_in_h  input)

Drops the 'audio in' buffer that was peeked into.

This function works correctly only with read callback. Otherwise it won't operate as intended.

Since :
2.3.1
Remarks:
Works only in asynchronous (event) mode. This will remove 'audio in' data from the actual stream buffer. Use this if peeked data is not needed anymore.
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_INVALID_OPERATIONInvalid operation
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Precondition:
The state should be AUDIO_IO_STATE_RUNNING.
See also:
audio_in_peek()
int audio_in_flush ( audio_in_h  input)

Flushes and discards buffered audio data from the input stream.

Since :
3.0
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Precondition:
The state should be AUDIO_IO_STATE_RUNNING or AUDIO_IO_STATE_PAUSED.
int audio_in_get_buffer_size ( audio_in_h  input,
int *  size 
)

Gets the size to be allocated for the audio input buffer.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
[out]sizeThe buffer size (in bytes, the maximum size is 1 MB)
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
See also:
audio_in_read()
int audio_in_get_channel ( audio_in_h  input,
audio_channel_e channel 
)

Gets the channel type of the audio input data stream.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
[out]channelThe audio channel type
Before 5.5: Mono or stereo
Since 5.5: Mono, stereo or multi-channels
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
int audio_in_get_sample_rate ( audio_in_h  input,
int *  sample_rate 
)

Gets the sample rate of the audio input data stream.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
[out]sample_rateThe audio sample rate
Before 5.0: 8000[Hz] ~ 48000[Hz]
Since 5.0: 8000[Hz] ~ 192000[Hz]
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported

Gets the sample audio format of the audio input data stream.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
[out]typeThe type of audio sample
Before 5.0: 8 or 16-bit
Since 5.0: 8, 16 or 24-bit
Since 5.5: 8, 16, 24 or 32-bit
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
int audio_in_pause ( audio_in_h  input)

Pauses buffering of audio data from the device.

Since :
3.0
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Precondition:
The state should be AUDIO_IO_STATE_RUNNING.
Postcondition:
The state will be AUDIO_IO_STATE_PAUSED.
See also:
audio_in_resume()
int audio_in_peek ( audio_in_h  input,
const void **  buffer,
unsigned int *  length 
)

Peeks into the 'audio in' buffer.

This function works correctly only with read callback. Otherwise it won't operate as intended.

Since :
2.3.1
Remarks:
Works only in asynchronous (event) mode. This function provides the pointer to the 'audio in' buffer. The pointed memory is owned by the platform, therefore the buffer should not be released by the application. When the data in the buffer is not needed anymore, use audio_in_drop() with the input for which audio_in_peek() was called.
Parameters:
[in]inputThe handle to the audio input
[out]bufferstart buffer pointer of peeked 'audio in' data
[out]lengthamount of 'audio in' data to be peeked
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_INVALID_OPERATIONInvalid operation
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Precondition:
The state should be AUDIO_IO_STATE_RUNNING.
See also:
audio_in_drop()
int audio_in_prepare ( audio_in_h  input)

Prepares the audio input for reading audio data by starting buffering of audio data from the device.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_DEVICE_POLICY_RESTRICTIONDevice policy restriction
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Postcondition:
The state will be AUDIO_IO_STATE_RUNNING.
See also:
audio_in_unprepare()
int audio_in_read ( audio_in_h  input,
void *  buffer,
unsigned int  length 
)

Reads audio data from the audio input buffer.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
[out]bufferThe PCM buffer address
[in]lengthThe length of the PCM data buffer (in bytes)
Returns:
The number of read bytes on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_INVALID_BUFFERInvalid buffer pointer
AUDIO_IO_ERROR_SOUND_POLICYSound policy error
AUDIO_IO_ERROR_INVALID_OPERATIONInvalid operation
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
Precondition:
The state should be AUDIO_IO_STATE_RUNNING.
int audio_in_resume ( audio_in_h  input)

Resumes buffering audio data from the device.

Since :
3.0
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Precondition:
The state should be AUDIO_IO_STATE_PAUSED.
Postcondition:
The state will be AUDIO_IO_STATE_RUNNING.
See also:
audio_in_pause()

Sets the sound stream information to the audio input.

Since :
3.0
Remarks:
The sound stream information includes audio routing and volume type. For more details, you can refer to Sound Manager System, Alarm, Notification, Emergency, Voice Information, Ringtone VOIP and Ringtone Call stream types are not supported in this API.
Parameters:
[in]inputThe handle to the audio input
[in]stream_infoThe handle of stream information
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
AUDIO_IO_ERROR_NOT_SUPPORTED_TYPENot supported stream type
Precondition:
The state should be AUDIO_IO_STATE_IDLE.
Call audio_in_create() before calling this function.
Postcondition:
Call audio_in_prepare() after calling this function.
See also:
sound_manager_create_stream_information()
sound_manager_destroy_stream_information()
int audio_in_set_state_changed_cb ( audio_in_h  input,
audio_in_state_changed_cb  callback,
void *  user_data 
)

Sets the state changed callback function to the audio input handle.

Since :
3.0
Remarks:
input must be created using audio_in_create().
Parameters:
[in]inputThe audio input handle
[in]callbackthe state changed callback called when the state of the handle is changed (audio_in_state_changed_cb)
[in]user_datauser data to be retrieved when callback is called
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
See also:
audio_in_unset_state_changed_cb()
int audio_in_set_stream_cb ( audio_in_h  input,
audio_in_stream_cb  callback,
void *  user_data 
)

Sets an asynchronous (event) callback function to handle recording PCM (pulse-code modulation) data.

callback will be called when you can read a PCM data. It might cause dead lock if change the state of audio handle in callback. (ex: audio_in_destroy(), audio_in_prepare(), audio_in_unprepare()) Recommend to use as a VOIP only. Recommend not to hold callback too long.(it affects latency)

Since :
2.3.1
Remarks:
input must be created using audio_in_create().
Parameters:
[in]inputAn audio input handle
[in]callbacknotify stream callback when user can read data (audio_in_stream_cb)
[in]user_datauser data to be retrieved when callback is called
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_OUT_OF_MEMORYOut of memory
AUDIO_IO_ERROR_DEVICE_NOT_OPENEDDevice not opened
AUDIO_IO_ERROR_SOUND_POLICYSound policy error
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
See also:
audio_in_unset_stream_cb()

Unprepares the audio input.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
AUDIO_IO_ERROR_INVALID_STATEInvalid state
Postcondition:
The state will be AUDIO_IO_STATE_IDLE.
See also:
audio_in_prepare()

Unregisters the state changed callback function of the audio input handle.

Since :
3.0
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
See also:
audio_in_set_state_changed_cb()

Unregisters the callback function.

Since :
2.3.1
Parameters:
[in]inputThe handle to the audio input
Returns:
0 on success, otherwise a negative error value
Return values:
AUDIO_IO_ERROR_NONESuccessful
AUDIO_IO_ERROR_INVALID_PARAMETERInvalid parameter
AUDIO_IO_ERROR_INVALID_OPERATIONInvalid operation
AUDIO_IO_ERROR_NOT_SUPPORTEDNot supported
See also:
audio_in_set_stream_cb()