Voice Changer/Reverb/Stereo

Function Overview

In live streaming, voice chat rooms, and karaoke rooms scenarios, to increase fun and interactivity, players can use voice changing to be funny, use reverb to enhance the atmosphere, and use stereo to make sound more three-dimensional. ZegoExpress SDK provides various preset voice changer, reverb, reverb echo, and stereo effects. Developers can flexibly set the desired sound. If you need to preview, you can enable in-ear monitoring for testing.

• Voice Changer: By changing the user's pitch, the output sound is perceptually different from the original sound, achieving effects such as male voice changing to female voice.
• Reverb: Through special processing of sound, create reverb effects of different environments, making the sound appear as if it were in a concert hall, cathedral, etc.
• Reverb Echo: Through special processing of sound, it can be combined with voice changer and reverb to achieve various customized sound effects, such as ethereal, robotic sounds.
• Virtual Stereo: By deeply using dual-channel technology, virtualize various positions and angles of sound sources, achieving stereo, 3D surround sound, sound positioning, and other effects.

You can experience the SDK's preset voice effects through the Sound Effects Experience DEMO provided by ZEGO.

Example Source Code Download

Please refer to Download Example Source Code to get the source code.

For related source code, please check the files in the "lib\topics\AudioAdvanced\voice_change" directory.

Prerequisites

Before proceeding with Voice Changer/Reverb/Stereo, please ensure:

• ZEGO Express SDK has been integrated in the project and basic real-time audio and video functions have been implemented. For details, please refer to Quick Start - Integration and Quick Start - Implementation.
• A project has been created in the ZEGOCLOUD Console and valid AppID and AppSign have been applied. For details, please refer to Console - Project Information.

Usage Steps

Voice Changer

There are two ways to set voice changer: preset voice changer and custom voice changer.

Set Preset Voice Changer

Call the setVoiceChangerPreset method to use the SDK's preset voice changer effects.

The preset voice changer effects of ZegoVoiceChangerPreset are as follows. Developers can choose according to their needs:

The following example code uses "Male to Child Voice" as an example:

ZegoExpressEngine.instance.setVoiceChangerPreset(ZegoVoiceChangerPreset.MenToChild);

ZegoExpressEngine.instance.setVoiceChangerPreset(ZegoVoiceChangerPreset.MenToChild);

Set Custom Voice Changer

If the SDK's preset voice changer effects cannot meet your needs, developers can call the ZegoVoiceChangerParam method and set custom voice changer through the pitch parameter "pitch". The value range of this parameter is [-12.0, 12.0]. The larger the value, the sharper the sound. The default value is "0.0" (i.e., no voice changer).

var voiceChangerParam = ZegoVoiceChangerParam(2.0);
ZegoExpressEngine.instance.setVoiceChangerParam(ZegoMediaPlayerAudioChannel.All, param);

var voiceChangerParam = ZegoVoiceChangerParam(2.0);
ZegoExpressEngine.instance.setVoiceChangerParam(ZegoMediaPlayerAudioChannel.All, param);

Reverb

There are two ways to set reverb: preset reverb and custom reverb.

Set Preset Reverb

Call setReverbPreset to set reverb through preset enumeration.

The preset reverb effects of ZegoReverbPreset are as follows. Developers can choose according to their needs:

The following example code uses "Large Room" mode as an example:

ZegoExpressEngine.instance.setReverbPreset(ZegoReverbPreset.LargeRoom);

ZegoExpressEngine.instance.setReverbPreset(ZegoReverbPreset.LargeRoom);

Set Custom Reverb

If the SDK's preset reverb types cannot meet your needs, developers can call the ZegoReverbAdvancedParam method and set relevant parameters in combination to achieve the reverb effect developers need (for detailed parameter description, please refer to the API documentation).

var reverbParam = ZegoReverbAdvancedParam(
    50.0, // roomSize Room size (percentage)
    50.0, // reverberance Reverberation (percentage)
    50.0, // damping Reverb damping (percentage)
    false, // wetOnly Wet signal only
    5.0, // wetGain Wet signal gain(dB)
    5.0, // dryGain Dry signal gain(dB)
    80.0, // toneLow Low frequency attenuation
    80.0, // toneHigh High frequency attenuation
    20.0, // preDelay Initial delay time(ms)
    0.0 // stereoWidth Stereo width (percentage)
   );
ZegoExpressEngine.instance.setReverbAdvancedParam(reverbParam);

var reverbParam = ZegoReverbAdvancedParam(
    50.0, // roomSize Room size (percentage)
    50.0, // reverberance Reverberation (percentage)
    50.0, // damping Reverb damping (percentage)
    false, // wetOnly Wet signal only
    5.0, // wetGain Wet signal gain(dB)
    5.0, // dryGain Dry signal gain(dB)
    80.0, // toneLow Low frequency attenuation
    80.0, // toneHigh High frequency attenuation
    20.0, // preDelay Initial delay time(ms)
    0.0 // stereoWidth Stereo width (percentage)
   );
ZegoExpressEngine.instance.setReverbAdvancedParam(reverbParam);

Reverb Echo

Call the setReverbEchoParam method and set relevant parameters in combination to achieve the reverb echo effect developers need (for detailed parameter description, please refer to the API documentation).

The following example code takes implementing "ethereal sound effect" as an example:

var echoParam = ZegoReverbEchoParam(
    0.8, // inGain Input audio signal gain
    1.0, // outGain Output audio signal gain
    7, // numDelays Number of echoes
    [230,460,690,920,1150,1380,1610], // delay Delay of echo signals respectively, in milliseconds
    [0.41f,0.18f,0.08f,0.03f,0.009f,0.003f,0.001f] // decay Decay coefficient of echo signals respectively
    );
ZegoExpressEngine.instance.setReverbEchoParam(echoParam);

var echoParam = ZegoReverbEchoParam(
    0.8, // inGain Input audio signal gain
    1.0, // outGain Output audio signal gain
    7, // numDelays Number of echoes
    [230,460,690,920,1150,1380,1610], // delay Delay of echo signals respectively, in milliseconds
    [0.41f,0.18f,0.08f,0.03f,0.009f,0.003f,0.001f] // decay Decay coefficient of echo signals respectively
    );
ZegoExpressEngine.instance.setReverbEchoParam(echoParam);

Virtual Stereo

Set Publishing Audio Channel Count

If you need to enable the virtual stereo function, you must call the setAudioConfig method before publishing to set the audio encoding channel to Stereo dual channel (the default is Mono single channel).

This example constructs ZegoAudioConfig through preset enumeration and sets it to dual channel.

var audioConfig = ZegoAudioConfig.preset(ZegoAudioConfigPreset.StandardQualityStereo);
ZegoExpressEngine.instance.setAudioConfig(audioConfig);

var audioConfig = ZegoAudioConfig.preset(ZegoAudioConfigPreset.StandardQualityStereo);
ZegoExpressEngine.instance.setAudioConfig(audioConfig);

Set Virtual Stereo Parameters

After setting the audio encoding channel to dual channel, call the enableVirtualStereo method and set the virtual stereo source angle through the enable parameter to have a stereo effect. The angle range is 0 ~ 360. Generally, it can be set to 90 degrees (i.e., directly in front).

This example enables virtual stereo and sets the angle to 90 degrees:

ZegoExpressEngine.instance.enableVirtualStereo(true, 90);

ZegoExpressEngine.instance.enableVirtualStereo(true, 90);

This example enables all-around virtual stereo:

ZegoExpressEngine.instance.enableVirtualStereo(true, -1);

ZegoExpressEngine.instance.enableVirtualStereo(true, -1);