Docs Overview/
RTC Engine/
SDK/
Windows/
Client APIs/
ITXDeviceManager/

ITXDeviceManager

Copyright (c) 2021 Tencent. All rights reserved.

Module: audio/video device management module

Description: manages audio/video devices such as camera, mic, and speaker.

ITXDeviceManager

ITXDeviceManager

FuncList
DESC
Querying whether the front camera is being used
Switching to the front/rear camera (for mobile OS)
Getting the maximum zoom ratio of the camera (for mobile OS)
Setting the camera zoom ratio (for mobile OS)
Querying whether automatic face detection is supported (for mobile OS)
Enabling auto focus (for mobile OS)
Adjusting the focus (for mobile OS)
Enabling/Disabling flash, i.e., the torch mode (for mobile OS)
Setting the audio route (for mobile OS)
Getting the device list (for desktop OS)
Setting the device to use (for desktop OS)
Getting the device currently in use (for desktop OS)
Setting the volume of the current device (for desktop OS)
Getting the volume of the current device (for desktop OS)
Muting the current device (for desktop OS)
Querying whether the current device is muted (for desktop OS)
Set the audio device used by SDK to follow the system default device (for desktop OS)
Starting camera testing (for desktop OS)
Ending camera testing (for desktop OS)
Starting mic testing (for desktop OS)
Starting mic testing (for desktop OS)
Ending mic testing (for desktop OS)
Starting speaker testing (for desktop OS)
Ending speaker testing (for desktop OS)
Starting camera testing (for desktop OS)
Setting the volume of the current process in the volume mixer (for Windows)
Getting the volume of the current process in the volume mixer (for Windows)
Muting the current process in the volume mixer (for Windows)
Querying whether the current process is muted in the volume mixer (for Windows)
Set camera acquisition preferences
set onDeviceChanged callback
Setting the system volume type (for mobile OS)

StructType

FuncList
DESC
Camera acquisition parameters
Audio/Video device information (for desktop OS)
Device information list (for desktop OS)

EnumType

EnumType
DESC
System volume type
Audio route (the route via which audio is played)
Device type (for desktop OS)
Device operation
Camera acquisition preferences

isFrontCamera

isFrontCamera

Querying whether the front camera is being used

switchCamera

switchCamera
int switchCamera
(bool frontCamera)

Switching to the front/rear camera (for mobile OS)

getCameraZoomMaxRatio

getCameraZoomMaxRatio

Getting the maximum zoom ratio of the camera (for mobile OS)

setCameraZoomRatio

setCameraZoomRatio
int setCameraZoomRatio
(float zoomRatio)

Setting the camera zoom ratio (for mobile OS)

Param
DESC
zoomRatio
Value range: 1-5. 1 indicates the widest angle of view (original), and 5 the narrowest angle of view (zoomed in).The maximum value is recommended to be 5. If the value exceeds 5, the video will become blurred.

isAutoFocusEnabled

isAutoFocusEnabled

Querying whether automatic face detection is supported (for mobile OS)

enableCameraAutoFocus

enableCameraAutoFocus
int enableCameraAutoFocus
(bool enabled)

Enabling auto focus (for mobile OS)

After auto focus is enabled, the camera will automatically detect and always focus on faces.

setCameraFocusPosition

setCameraFocusPosition
int setCameraFocusPosition
(float x

float y)

Adjusting the focus (for mobile OS)

This API can be used to achieve the following:
1. A user can tap on the camera preview.
2. A rectangle will appear where the user taps, indicating the spot the camera will focus on.
3. The user passes the coordinates of the spot to the SDK using this API, and the SDK will instruct the camera to focus as required.
Param
DESC
position
The spot to focus on. Pass in the coordinates of the spot you want to focus on.
Note
Before using this API, you must first disable auto focus using enableCameraAutoFocus.

Return Desc:

0: operation successful; negative number: operation failed.

enableCameraTorch

enableCameraTorch
int enableCameraTorch
(bool enabled)

Enabling/Disabling flash, i.e., the torch mode (for mobile OS)

setAudioRoute

setAudioRoute
int setAudioRoute
(TXAudioRoute route)

Setting the audio route (for mobile OS)

A mobile phone has two audio playback devices: the receiver at the top and the speaker at the bottom.
If the audio route is set to the receiver, the volume is relatively low, and audio can be heard only when the phone is put near the ear. This mode has a high level of privacy and is suitable for answering calls.
If the audio route is set to the speaker, the volume is relatively high, and there is no need to put the phone near the ear. This mode enables the "hands-free" feature.

getDevicesList

getDevicesList
ITXDeviceCollection* getDevicesList
(TXMediaDeviceType type)

Getting the device list (for desktop OS)

Param
DESC
type
Device type. Set it to the type of device you want to get. For details, please see the definition of TXMediaDeviceType .
Note
To ensure that the SDK can manage the lifecycle of the ITXDeviceCollection object, after using this API, please call the release method to release the resources.
Do not use delete to release the Collection object returned as deleting the ITXDeviceCollection* pointer will cause crash.
The valid values of type are TXMediaDeviceTypeMic , TXMediaDeviceTypeSpeaker , and TXMediaDeviceTypeCamera .
This API can be used only on macOS and Windows.

setCurrentDevice

setCurrentDevice
int setCurrentDevice
(TXMediaDeviceType type

const char* deviceId)

Setting the device to use (for desktop OS)

Param
DESC
deviceId
Device ID. You can get the ID of a device using the getDevicesList API.
type
Device type. For details, please see the definition of TXMediaDeviceType .

Return Desc:

0: operation successful; negative number: operation failed.

getCurrentDevice

getCurrentDevice
ITXDeviceInfo* getCurrentDevice
(TXMediaDeviceType type)

Getting the device currently in use (for desktop OS)

setCurrentDeviceVolume

setCurrentDeviceVolume
int setCurrentDeviceVolume
(TXMediaDeviceType type

uint32_t volume)

Setting the volume of the current device (for desktop OS)

This API is used to set the capturing volume of the mic or playback volume of the speaker, but not the volume of the camera.
Param
DESC
volume
Volume. Value range: 0-100; default: 100

getCurrentDeviceVolume

getCurrentDeviceVolume
uint32_t getCurrentDeviceVolume
(TXMediaDeviceType type)

Getting the volume of the current device (for desktop OS)

This API is used to get the capturing volume of the mic or playback volume of the speaker, but not the volume of the camera.

setCurrentDeviceMute

setCurrentDeviceMute
int setCurrentDeviceMute
(TXMediaDeviceType type

bool mute)

Muting the current device (for desktop OS)

This API is used to mute the mic or speaker, but not the camera.

getCurrentDeviceMute

getCurrentDeviceMute
bool getCurrentDeviceMute
(TXMediaDeviceType type)

Querying whether the current device is muted (for desktop OS)

This API is used to query whether the mic or speaker is muted. Camera muting is not supported.

enableFollowingDefaultAudioDevice

enableFollowingDefaultAudioDevice
int enableFollowingDefaultAudioDevice
(TXMediaDeviceType type

bool enable)

Set the audio device used by SDK to follow the system default device (for desktop OS)

This API is used to set the microphone and speaker types. Camera following the system default device is not supported.
Param
DESC
enable
Whether to follow the system default audio device.
true: following. When the default audio device of the system is changed or new audio device is plugged in, the SDK immediately switches the audio device.
false：not following. When the default audio device of the system is changed or new audio device is plugged in, the SDK doesn't switch the audio device.
type
Device type. For details, please see the definition of TXMediaDeviceType .

startCameraDeviceTest

startCameraDeviceTest
int startCameraDeviceTest
(void* view)

Starting camera testing (for desktop OS)

Note
You can use the setCurrentDevice API to switch between cameras during testing.

stopCameraDeviceTest

stopCameraDeviceTest

Ending camera testing (for desktop OS)

startMicDeviceTest

startMicDeviceTest
int startMicDeviceTest
(uint32_t interval)

Starting mic testing (for desktop OS)

This API is used to test whether the mic functions properly. The mic volume detected (value range: 0-100) is returned via a callback.
Param
DESC
interval
Interval of volume callbacks
Note
When this interface is called, the sound recorded by the microphone will be played back to the speakers by default.

startMicDeviceTest

startMicDeviceTest
int startMicDeviceTest
(uint32_t interval

bool playback)

Starting mic testing (for desktop OS)

This API is used to test whether the mic functions properly. The mic volume detected (value range: 0-100) is returned via a callback.
Param
DESC
interval
Interval of volume callbacks
playback
Whether to play back the microphone sound. The user will hear his own sound when testing the microphone if playback is true.

stopMicDeviceTest

stopMicDeviceTest

Ending mic testing (for desktop OS)

startSpeakerDeviceTest

startSpeakerDeviceTest
int startSpeakerDeviceTest
(const char* filePath)

Starting speaker testing (for desktop OS)

This API is used to test whether the audio playback device functions properly by playing a specified audio file. If users can hear audio during testing, the device functions properly.
Param
DESC
filePath
Path of the audio file

stopSpeakerDeviceTest

stopSpeakerDeviceTest

Ending speaker testing (for desktop OS)

startCameraDeviceTest

startCameraDeviceTest
int startCameraDeviceTest
(ITRTCVideoRenderCallback* callback)

Starting camera testing (for desktop OS)

This API supports custom rendering, meaning that you can use the callback API ITRTCVideoRenderCallback to get the images captured by the camera for custom rendering.

setApplicationPlayVolume

setApplicationPlayVolume
int setApplicationPlayVolume
(int volume)

Setting the volume of the current process in the volume mixer (for Windows)

getApplicationPlayVolume

getApplicationPlayVolume

Getting the volume of the current process in the volume mixer (for Windows)

setApplicationMuteState

setApplicationMuteState
int setApplicationMuteState
(bool bMute)

Muting the current process in the volume mixer (for Windows)

getApplicationMuteState

getApplicationMuteState

Querying whether the current process is muted in the volume mixer (for Windows)

setCameraCapturerParam

setCameraCapturerParam
void setCameraCapturerParam
(const TXCameraCaptureParam& params)

Set camera acquisition preferences

setDeviceObserver

setDeviceObserver
void setDeviceObserver
(ITXDeviceObserver* observer)

set onDeviceChanged callback

setSystemVolumeType

setSystemVolumeType
int setSystemVolumeType
(TXSystemVolumeType type)

Setting the system volume type (for mobile OS)

@deprecated This API is not recommended after v9.5. Please use the startLocalAudio(quality) API in TRTCCloud instead, which param quality is used to decide audio quality.

TXSystemVolumeType(Deprecated)

TXSystemVolumeType(Deprecated)

System volume type

Enum
Value
DESC
TXSystemVolumeTypeAuto
0
Auto
TXSystemVolumeTypeMedia
1
Media volume
TXSystemVolumeTypeVOIP
2
Call volume

TXAudioRoute

TXAudioRoute

Audio route (the route via which audio is played)

Audio route is the route (speaker or receiver) via which audio is played. It applies only to mobile devices such as mobile phones.
A mobile phone has two speakers: one at the top (receiver) and the other the bottom.
If the audio route is set to the receiver, the volume is relatively low, and audio can be heard only when the phone is put near the ear. This mode has a high level of privacy and is suitable for answering calls.
If the audio route is set to the speaker, the volume is relatively high, and there is no need to put the phone near the ear. This mode enables the "hands-free" feature.
Enum
Value
DESC
TXAudioRouteSpeakerphone
0
Speakerphone: the speaker at the bottom is used for playback (hands-free). With relatively high volume, it is used to play music out loud.
TXAudioRouteEarpiece
1
Earpiece: the receiver at the top is used for playback. With relatively low volume, it is suitable for call scenarios that require privacy.

TXMediaDeviceType

TXMediaDeviceType

Device type (for desktop OS)

This enumerated type defines three types of audio/video devices, namely camera, mic and speaker, so that you can use the same device management API to manage three types of devices.
Enum
Value
DESC
TXMediaDeviceTypeUnknown
-1
undefined device type
TXMediaDeviceTypeMic
0
microphone
TXMediaDeviceTypeSpeaker
1
speaker or earpiece
TXMediaDeviceTypeCamera
2
camera

TXMediaDeviceState

TXMediaDeviceState

Device operation

This enumerated value is used to notify the status change of the local device onDeviceChanged.
Enum
Value
DESC
TXMediaDeviceStateAdd
0
The device has been plugged in
TXMediaDeviceStateRemove
1
The device has been removed
TXMediaDeviceStateActive
2
The device has been enabled
TXMediaDefaultDeviceChanged
3
system default device changed

TXCameraCaptureMode

TXCameraCaptureMode

Camera acquisition preferences

This enum is used to set camera acquisition parameters.
Enum
Value
DESC
TXCameraResolutionStrategyAuto
0
Auto adjustment of camera capture parameters.
SDK selects the appropriate camera output parameters according to the actual acquisition device performance and network situation, and maintains a balance between device performance and video preview quality.
TXCameraResolutionStrategyPerformance
1
Give priority to equipment performance.
SDK selects the closest camera output parameters according to the user's encoder resolution and frame rate, so as to ensure the performance of the device.
TXCameraResolutionStrategyHighQuality
2
Give priority to the quality of video preview.
SDK selects higher camera output parameters to improve the quality of preview video. In this case, it will consume more CPU and memory to do video preprocessing.
TXCameraCaptureManual
3
Allows the user to set the width and height of the video captured by the local camera.

TXCameraCaptureParam

TXCameraCaptureParam

Camera acquisition parameters

This setting determines the quality of the local preview image.
EnumType
DESC
height
Field description: height of acquired image
mode
Field description: camera acquisition preferences,please see TXCameraCaptureMode
width
Field description: width of acquired image

TXMediaDeviceInfo

TXMediaDeviceInfo

Audio/Video device information (for desktop OS)

This structure describes key information (such as device ID and device name) of an audio/video device, so that users can choose on the UI the device to use.
EnumType
DESC
getDeviceName()
device name (UTF-8)
getDevicePID()
device id (UTF-8)

ITXDeviceCollection

ITXDeviceCollection

Device information list (for desktop OS)

This structure functions as std::vector<ITXDeviceInfo> does. It solves the binary compatibility issue between different versions of STL containers.
EnumType
DESC
getCount()
Size of this list. return Size of this list.
index)
device properties (json format)
Note

examples: {"SupportedResolution":[{"width":640,"height":480},{"width":320,"height":240}]}
param index value in [0,getCount),return device properties formatted by json
release()
release function, don't use delete!!!