Vivox: How to: Access VAD settings

In most cases, customers do not need to adjust the default voice activity detection (VAD) settings of the Vivox SDK. However, the ability to adjust VAD is provided, if needed.

To begin the VAD tuning process, try enabling the Automatically Adjusted VAD before trying your own values for the VAD settings. Do this by enabling the vad_auto in the vx_req_aux_set_vad_properties call, as detailed in the examples in the following sections. Any values provided for the other parameters are ignored when the vad_auto is enabled. If the Automatically Adjusted VAD does not help, disable the vad_auto setting and provide your own values for vad_hangover, vad_sensitivity, and vad_noise_floor.

Important: Changes to the VAD noise floor settings do not take effect for currently joined channels. Also, if the ability to change VAD settings is presented to the end-user, indicate that noise floor changes only take effect in the next voice session or only allow changing the noise floor channel when the client is not in-channel.

Parameter specifics

vad_hangover

The hangover time is the time (in milliseconds) that it takes for the VAD to switch back to silence from speech mode after the last speech frame has been detected. The default value is 2000.

vad_sensitivity

The sensitivity is a dimensionless value between 0 and 100 and indicates the sensitivity of the VAD. Increasing this value corresponds to decreasing the sensitivity of the VAD (0 is most sensitive, and 100 is least sensitive). Higher values of sensitivity require louder audio to trigger the VAD. The default value is 43.

vad_noise_floor

The noise floor is a dimensionless value between 0 and 20000 that controls how the VAD separates speech from background noise. Lower values assume that the user is in a quieter environment where the audio is only speech. Higher values assume a noisy background environment. The default value is 576.

Core

To make adjustments to the VAD settings, you work with the vx_req_aux_set_vad_properties and vx_req_aux_get_vad_properties structs in the Vivox Core SDK. You can read more about the VAD requests and responses in the Vivox Core API documentation by searching for the following terms:

Users who are familiar with the Vivox Core SDK can use the same requests and response handling that are used in the rest of the Core SDK. For more information, see Requests and responses in the Vivox Developer Documentation.

Enabling VAD Automatic Parameter Selection

vx_req_aux_set_vad_properties_t *req;
vx_req_aux_set_vad_properties_create(&req);
req->vad_hangover = 2000;
req->vad_sensitivity = 43;
req->vad_noise_floor = 576;
req->vad_auto = 1;
vx_issue_request(&req->base);

Note: Although the VAD ignores the other settings when vad_auto is enabled, valid parameters must be provided or the call will return an error. In this example, the default values for the vad_hangover, vad_sensitivity, and vad_noise_floor have been provided.

Setting the VAD Hangover, Sensitivity, and Noise Floor

vx_req_aux_set_vad_properties_t *req;
vx_req_aux_set_vad_properties_create(&req);
req->vad_hangover = 2000;
req->vad_sensitivity = 43;
req->vad_noise_floor = 576;
req->vad_auto = 0;
vx_issue_request(&req->base);

Note: In this example, the default values for the vad_hangover, vad_sensitivity, and vad_noise_floor have been provided. vad_auto has been disabled.

Unity

To set the VAD properties, you need to add support for the vx_req_aux_set_vad_properties request from the Core SDK. You can read more about the request and responses in the Vivox Core API documentation by searching for the following terms:

By using these requests and handling their responses, you should be able to manipulate the VAD mic gating. For more information, see Requests and responses in the Vivox Developer Documentation. Note that although this information refers to the Core SDK, the Vivox Core Unity source package is designed to follow a very similar flow.

You can find examples of requests and responses in the Unity source package by looking under VivoxUnity project. This is located in the source release in vivox_unity\vivox_unity.sln.

To use vx_req_aux_set_vad_properties and vx_req_aux_get_vad_properties, you need to add these requests to an existing endpoint or an exposed function of the Unity API or create a new endpoint. To confirm whether your requests are successful, ensure that you handle the responses. You can find numerous examples of request and response handling throughout the source code by searching for how VxClient.Instance.BeginIssueRequest is used. One possible example is the ILoginSession.BeginAccountSetLoginProperties call, in which you can see a simple request and response being handled.

When these calls are added, using the calls is similar to what is shown in the Core example.

Unreal

Currently, the Vivox Unreal SDK does not provide an API to adjust the VAD settings. If you want to modify the code for the Unreal wrapper, you can add support for at least the vx_req_aux_set_vad_properties request from the Core SDK. You can read more about the VAD requests and responses in the Vivox Core API documentation by searching for the following terms:

By using these requests and handling their responses, you should be able to manipulate the VAD mic gating. For more information, see Requests and responses in the Vivox Developer Documentation.

To use vx_req_aux_set_vad_properties and vx_req_aux_get_vad_properties, you need to add these requests to an existing endpoint or an exposed function of the Unity API, or create a new endpoint. To confirm whether your requests are successful, ensure that you handle the responses. You can find examples of request and response handling throughout the source code by searching for how VivoxNativeSdk::IssueRequest is used. One possible example is the VivoxNativeSdk::SetActiveAudioInputDevice call, in which you can see a simple request being handled.

When these calls are added, using the calls is similar to what is shown in the Core example.