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移除书签- MultiMedia_AudioCapturer
- Overview
- Summary
- Files
- Data Structures
- Enumerations
- Functions
- Details
- Enumeration Type Documentation
- State
- Timebase
- Function Documentation
- GetAudioTime()
- GetCapturerInfo()
- GetFrameCount()
- GetMinFrameCount()
- GetStatus()
- Read()
- Release()
- SetCapturerInfo()
- Start()
- Stop()
- Variable Documentation
- audioFormat
- bitRate
- bitWidth
- channelCount
- inputSource
- sampleRate
- streamType
MultiMedia_AudioCapturer
Overview
Declares APIs in the AudioCapturer class for audio capture.
Since:
1.0
Version:
1.0
Summary
Files
| File Name | Description |
|---|---|
| audio_capturer.h | Provides the AudioCapturer class to implement operations related to audio capture. |
Data Structures
| Data Structure Name | Description |
|---|---|
| OHOS::Audio::AudioCapturerInfo | Defines information about audio capture parameters, including the input source, audio codec format,sampling rate (Hz), number of audio channels, bit rate, and bit width. |
| OHOS::Audio::Timestamp | Represents timestamp information, including the frame position information and high-resolution time source. |
| OHOS::Audio::AudioCapturer | Provides functions for applications to implement audio capturing. |
Enumerations
| Enumeration Name | Description |
|---|---|
| OHOS::Audio::Timestamp::Timebase : int32_t { OHOS::Audio::Timestamp::Timebase::MONOTONIC = 0, OHOS::Audio::Timestamp::Timebase::BOOTTIME = 1 } | Enumerates the time base of this Timestamp. Different timing methods are supported. |
| OHOS::Audio::State : uint32_t { OHOS::Audio::PREPPARED, OHOS::Audio::RECORDING, OHOS::Audio::STOPPED, OHOS::Audio::RELEASED } | Enumerates the recording states of the current device. |
Functions
| Function Name | Description |
|---|---|
| OHOS::Audio::AudioCapturer::GetMinFrameCount (int32_t sampleRate, int32_t channelCount, AudioCodecFormat audioFormat, size_t &frameCount) | static bool Obtains the minimum number of frames required in a specified condition, in bytes per sample. |
| OHOS::Audio::AudioCapturer::GetFrameCount () | uint64_t Obtains the number of frames required in the current condition, in bytes per sample. |
| OHOS::Audio::AudioCapturer::SetCapturerInfo (const AudioCapturerInfo info) | int32_t Sets audio capture parameters. |
| OHOS::Audio::AudioCapturer::GetCapturerInfo (AudioCapturerInfo &info) | int32_t Obtains audio capture parameters. |
| OHOS::Audio::AudioCapturer::Start () | bool Starts audio recording. |
| OHOS::Audio::AudioCapturer::Read (uint8_t *buffer, size_t userSize, bool isBlockingRead) | int32_t Reads audio data. |
| OHOS::Audio::AudioCapturer::GetStatus () | State Obtains the audio capture state. |
| OHOS::Audio::AudioCapturer::GetAudioTime (Timestamp ×tamp, Timestamp::Timebase base) | bool Obtains the timestamp. |
| OHOS::Audio::AudioCapturer::Stop () | bool Stops audio recording. |
| OHOS::Audio::AudioCapturer::Release () | bool Releases a local AudioCapturer object. |
Details
Enumeration Type Documentation
State
1. enum [OHOS::Audio::State]($api-api-SmartVision-Devices-MultiMedia_AudioCapturer.md#ga3d8d6798a2346e57e241d16da673d508) : uint32_t
Description:
Enumerates the recording states of the current device.
| Enumerator | Description |
|---|---|
| PREPPARED | Prepared |
| RECORDING | Recording |
| STOPPED | Stopped |
| RELEASED | Released |
Timebase
1. enum [OHOS::Audio::Timestamp::Timebase]($api-api-SmartVision-Devices-MultiMedia_AudioCapturer.md#gacdafb362a7da91799fa96163bca2a619) : int32_t
Description:
Enumerates the time base of this Timestamp. Different timing methods are supported.
| Enumerator | Description |
|---|---|
| MONOTONIC | Monotonically increasing time, excluding the system sleep time |
| BOOTTIME | Monotonically increasing time, including the system sleep time |
Function Documentation
GetAudioTime()
1. bool OHOS::Audio::AudioCapturer::GetAudioTime ([Timestamp]($api-api-SmartVision-Devices-OHOS-Audio-Timestamp.md) & timestamp, [Timestamp::Timebase]($api-api-SmartVision-Devices-MultiMedia_AudioCapturer.md#gacdafb362a7da91799fa96163bca2a619) base )
Description:
Obtains the timestamp.
Parameters:
| Name | Description |
|---|---|
| timestamp | Indicates a Timestamp instance reference provided by the caller. |
| base | Indicates the time base, which can be Timestamp.Timebase.BOOTTIME or Timestamp.Timebase.MONOTONIC. |
Returns:
Returns true if the timestamp is successfully obtained; returns false otherwise.
GetCapturerInfo()
1. int32_t OHOS::Audio::AudioCapturer::GetCapturerInfo ([AudioCapturerInfo]($api-api-SmartVision-Devices-OHOS-Audio-AudioCapturerInfo.md) & info)
Description:
Obtains audio capture parameters.
This function can be called after SetCapturerInfo is successful.
Parameters:
| Name | Description |
|---|---|
| info | Indicates information about audio capture parameters. For details, see AudioCapturerInfo. |
Returns:
Returns SUCCESS if the parameter information is successfully obtained; returns an error code defined in media_errors.h otherwise.
GetFrameCount()
1. uint64_t OHOS::Audio::AudioCapturer::GetFrameCount ()
Description:
Obtains the number of frames required in the current condition, in bytes per sample.
Returns:
Returns the number of frames (in bytes per sample) if the operation is successful; returns -1 if an exception occurs.
GetMinFrameCount()
1. static bool OHOS::Audio::AudioCapturer::GetMinFrameCount (int32_t sampleRate, int32_t channelCount, [AudioCodecFormat]($api-api-SmartVision-Devices-MultiMedia_MediaCommon.md#gaa4ea6f314644ed287e0704be26c768b7) audioFormat, size_t & frameCount )
Description:
Obtains the minimum number of frames required in a specified condition, in bytes per sample.
Parameters:
| Name | Description |
|---|---|
| sampleRate | Indicates the audio sampling rate, in Hz. |
| channelCount | Indicates the number of audio recording channels. |
| audioFormat | Indicates the audio data format. |
| frameCount | Indicates the minimum number of frames, in bytes per sample. |
Returns:
Returns true if the minimum number of frames is successfully obtained; returns false otherwise.
GetStatus()
1. [State]($api-api-SmartVision-Devices-MultiMedia_AudioCapturer.md#ga3d8d6798a2346e57e241d16da673d508) OHOS::Audio::AudioCapturer::GetStatus ()
Description:
Obtains the audio capture state.
Returns:
Returns the audio capture state defined in State.
Read()
1. int32_t OHOS::Audio::AudioCapturer::Read (uint8_t * buffer, size_t userSize, bool isBlockingRead )
Description:
Reads audio data.
Parameters:
| Name | Description |
|---|---|
| buffer | Indicates the pointer to the buffer into which the audio data is to be written. |
| userSize | Indicates the size of the buffer into which the audio data is to be written, in bytes. userSize >= frameCount channelCount BytesPerSample must evaluate to true. You can call GetFrameCount to obtain the frameCount value. |
| isBlockingRead | Specifies whether data reading will be blocked. |
Returns:
Returns the size of the audio data read from the device. The value ranges from 0 to userSize. If the reading fails, one of the following error codes is returned: ERR_INVALID_PARAM: The input parameter is incorrect. ERR_ILLEGAL_STATE: The AudioCapturer instance is not initialized. ERR_SOURCE_NOT_SET: The state of hardware device instance is abnormal.
Release()
1. bool OHOS::Audio::AudioCapturer::Release ()
Description:
Releases a local AudioCapturer object.
Returns:
Returns true if the object is successfully released; returns false otherwise.
SetCapturerInfo()
1. int32_t OHOS::Audio::AudioCapturer::SetCapturerInfo (const [AudioCapturerInfo]($api-api-SmartVision-Devices-OHOS-Audio-AudioCapturerInfo.md) info)
Description:
Sets audio capture parameters.
Parameters:
| Name | Description |
|---|---|
| info | Indicates information about audio capture parameters to set. For details, see AudioCapturerInfo. |
Returns:
Returns SUCCESS if the setting is successful; returns an error code defined in media_errors.h otherwise.
Start()
1. bool OHOS::Audio::AudioCapturer::Start ()
Description:
Starts audio recording.
Returns:
Returns true if the recording is successfully started; returns false otherwise.
Stop()
1. bool OHOS::Audio::AudioCapturer::Stop ()
Description:
Stops audio recording.
Returns:
Returns true if the recording is successfully stopped; returns false otherwise.
Variable Documentation
audioFormat
1. [AudioCodecFormat]($api-api-SmartVision-Devices-MultiMedia_MediaCommon.md#gaa4ea6f314644ed287e0704be26c768b7) OHOS::Audio::AudioCapturerInfo::audioFormat = [AUDIO_DEFAULT](MultiMedia_MediaCommon.md#ggaa4ea6f314644ed287e0704be26c768b7a4c4c5829b054bc468274700c56d65546)
Description:
Audio codec format
bitRate
1. int32_t OHOS::Audio::AudioCapturerInfo::bitRate = 0
Description:
Bit rate
bitWidth
1. [AudioBitWidth](MultiMedia_MediaCommon.md#gae3e35ee2a2222a667fdebbc5b793ca7c) OHOS::Audio::AudioCapturerInfo::bitWidth = [BIT_WIDTH_16](MultiMedia_MediaCommon.md#ggae3e35ee2a2222a667fdebbc5b793ca7ca036f0b45813f96cb6b0f90de1722a780)
Description:
Bit width
channelCount
1. int32_t OHOS::Audio::AudioCapturerInfo::channelCount = 0
Description:
Number of audio channels
inputSource
1. [AudioSourceType](MultiMedia_MediaCommon.md#gadc3158e093b995ca7b9b6aa32388ccdd) OHOS::Audio::AudioCapturerInfo::inputSource = [AUDIO_MIC](MultiMedia_MediaCommon.md#ggadc3158e093b995ca7b9b6aa32388ccdda732604b3a24d137429e2b83b31849bce)
Description:
Audio source type
sampleRate
1. int32_t OHOS::Audio::AudioCapturerInfo::sampleRate = 0
Description:
Sampling rate
streamType
1. [AudioStreamType](MultiMedia_MediaCommon.md#gae7077e4211e48131ae544adb20fc494a) OHOS::Audio::AudioCapturerInfo::streamType = [TYPE_MEDIA](MultiMedia_MediaCommon.md#ggae7077e4211e48131ae544adb20fc494aa431e273affaa22e18ec5a2a548b70e90)
Description:
Audio stream type
