Voice Changer/Reverb/Stereo

Feature Overview

In live streaming, voice chat room, and Karaoke room scenarios, to increase fun and interactivity, players can use voice changer to be funny, use reverb to set the atmosphere, and use stereo to make sound more three-dimensional. ZEGO Express SDK provides a variety of 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 to female voice.
• Reverb: Through special processing of sound, create reverb effects of different environments, making the sound as if it were emitted in concert halls, cathedrals, and other scenes.
• Reverb Echo: Through special processing of sound, can be combined with voice changer and reverb to achieve various customized sound effects, such as ethereal, robot sounds.
• Virtual Stereo: Through deep use of dual-channel technology, virtually generate various positions and angles of sound sources, achieving effects such as stereo, 3D surround sound, and sound positioning.

You can experience the SDK's preset vocal effects through ZEGO's Audio Effect Experience DEMO.

Example Source Code

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

For related source code, please check the files in the "/ZegoExpressExample/AdvancedAudioProcessing/src/main/java/im/zego/advancedaudioprocessing/voicechange" directory.

Prerequisites

Before implementing voice changer/reverb/stereo, please ensure:

• You have created a project in the ZEGOCLOUD Console and applied for a valid AppID and AppSign. For details, please refer to Console - Project Information.
• You have integrated ZEGO Express SDK in your project and implemented basic audio and video publish and play stream functionality. For details, please refer to Quick Start - Integration and Quick Start - Implementation.

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.

ZegoVoiceChangerPreset preset voice changer effects are as follows, developers can choose according to needs:

The following example code uses "Male voice to child voice" as an example:

ZegoExpressEngine.getEngine().setVoiceChangerPreset(ZegoVoiceChangerPreset.MEN_TO_CHILD);

ZegoExpressEngine.getEngine().setVoiceChangerPreset(ZegoVoiceChangerPreset.MEN_TO_CHILD);

Set custom voice changer

If the SDK's preset voice changer effects cannot meet your needs, developers can call the setVoiceChangerParam method in ZegoVoiceChangerParam to 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).

ZegoVoiceChangerParam voiceChangerParam = new ZegoVoiceChangerParam();
param.pitch = 2.0f;
ZegoExpressEngine.getEngine().setVoiceChangerParam(param);

ZegoVoiceChangerParam voiceChangerParam = new ZegoVoiceChangerParam();
param.pitch = 2.0f;
ZegoExpressEngine.getEngine().setVoiceChangerParam(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.

ZegoReverbPreset preset reverb effects are as follows, developers can choose according to needs:

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

ZegoExpressEngine.getEngine().setReverbPreset(ZegoReverbPreset.LARGE_ROOM);

ZegoExpressEngine.getEngine().setReverbPreset(ZegoReverbPreset.LARGE_ROOM);

Set custom reverb

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

ZegoReverbAdvancedParam reverbParam = new ZegoReverbAdvancedParam();
// Reverb damping
reverbParam.damping = 50.0;
// Reverberance
reverbParam.reverberance = 50.0;
// Room size
reverbParam.roomSize = 50.0;
// Wet only
reverbParam.wetOnly = false;
// Wet signal gain (dB), value range [-20.0, 10.0]
reverbParam.wetGain = 5.0;
// Dry signal gain (dB), value range [-20.0, 10.0]
reverbParam.dryGain = 5.0;
// Low frequency attenuation, defaults to no attenuation (100%)
reverbParam.toneLow = 80.0;
// High frequency attenuation, defaults to no attenuation (100%)
reverbParam.toneHigh = 80.0;
// Initial delay time (ms). Value range [0, 200]
reverbParam.preDelay = 20.0;
// Stereo width (percentage), default value is 0%
reverbParam.stereoWidth = 0.0;
ZegoExpressEngine.getEngine().setReverbAdvancedParam(reverbParam);

ZegoReverbAdvancedParam reverbParam = new ZegoReverbAdvancedParam();
// Reverb damping
reverbParam.damping = 50.0;
// Reverberance
reverbParam.reverberance = 50.0;
// Room size
reverbParam.roomSize = 50.0;
// Wet only
reverbParam.wetOnly = false;
// Wet signal gain (dB), value range [-20.0, 10.0]
reverbParam.wetGain = 5.0;
// Dry signal gain (dB), value range [-20.0, 10.0]
reverbParam.dryGain = 5.0;
// Low frequency attenuation, defaults to no attenuation (100%)
reverbParam.toneLow = 80.0;
// High frequency attenuation, defaults to no attenuation (100%)
reverbParam.toneHigh = 80.0;
// Initial delay time (ms). Value range [0, 200]
reverbParam.preDelay = 20.0;
// Stereo width (percentage), default value is 0%
reverbParam.stereoWidth = 0.0;
ZegoExpressEngine.getEngine().setReverbAdvancedParam(reverbParam);

Reverb Echo

Call the setReverbEchoParam method to achieve the required reverb echo effect through the combination of relevant parameters (for detailed parameter description, please refer to the API documentation).

The following example code implements "Ethereal sound effect":

ZegoReverbEchoParam echoParam = new ZegoReverbEchoParam();
// Gain of input audio signal, value range [0.0, 1.0]
echoParam.inGain= 0.8f;
// Gain of output audio signal, value range [0.0, 1.0]
echoParam.outGain =1.0f;
// Number of echoes, value range [0, 7]
echoParam.numDelays = 7;
// Delays of echo signals respectively, unit is milliseconds, value range [0, 5000] ms
int[] delay ={230,460,690,920,1150,1380,1610};
echoParam.delay=delay;
// Decay coefficients of echo signals respectively, value range [0.0, 1.0]
float[] decay={0.41f,0.18f,0.08f,0.03f,0.009f,0.003f,0.001f};
echoParam.decay=decay;
zegoReverbEchoParamDatas.add(echoParam);
ZegoExpressEngine.getEngine().setReverbEchoParam(echoParam);

ZegoReverbEchoParam echoParam = new ZegoReverbEchoParam();
// Gain of input audio signal, value range [0.0, 1.0]
echoParam.inGain= 0.8f;
// Gain of output audio signal, value range [0.0, 1.0]
echoParam.outGain =1.0f;
// Number of echoes, value range [0, 7]
echoParam.numDelays = 7;
// Delays of echo signals respectively, unit is milliseconds, value range [0, 5000] ms
int[] delay ={230,460,690,920,1150,1380,1610};
echoParam.delay=delay;
// Decay coefficients of echo signals respectively, value range [0.0, 1.0]
float[] decay={0.41f,0.18f,0.08f,0.03f,0.009f,0.003f,0.001f};
echoParam.decay=decay;
zegoReverbEchoParamDatas.add(echoParam);
ZegoExpressEngine.getEngine().setReverbEchoParam(echoParam);

Virtual Stereo

Set publish stream audio channel count

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

This example uses preset enumeration to construct ZegoAudioConfig to set to dual-channel.

ZegoAudioConfig audioConfig = new ZegoAudioConfig(STANDARD_QUALITY_STEREO);
ZegoExpressEngine.getEngine().setAudioConfig(audioConfig);

ZegoAudioConfig audioConfig = new ZegoAudioConfig(STANDARD_QUALITY_STEREO);
ZegoExpressEngine.getEngine().setAudioConfig(audioConfig);

Set virtual stereo parameters

After setting the audio encoding channel to dual-channel, call the enableVirtualStereo method, enable virtual stereo through the "enable" parameter, and set the sound source angle of virtual stereo through the "angle" parameter to achieve the stereo effect. The angle range is 0 to 360, generally can be set to 90 degrees (i.e., directly in front).

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

ZegoExpressEngine.getEngine().enableVirtualStereo(true, 90);

ZegoExpressEngine.getEngine().enableVirtualStereo(true, 90);

This example enables omni-directional virtual stereo:

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

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