录音时如何获取 当前输入的音量大小

audioManager.registerAudioCapturerCallback(callback);
AudioDeviceDescriptor[] devices = AudioManager.getDevices(AudioDeviceDescriptor.DeviceFlag.INPUT_DEVICES_FLAG);
AudioDeviceDescriptor currentAudioType = devices[0];
AudioCapturerInfo.AudioInputSource source = AudioCapturerInfo.AudioInputSource.AUDIO_INPUT_SOURCE_MIC;
AudioStreamInfo audioStreamInfo = new AudioStreamInfo.Builder().audioStreamFlag(
        AudioStreamInfo.AudioStreamFlag.AUDIO_STREAM_FLAG_AUDIBILITY_ENFORCED)
        .encodingFormat(AudioStreamInfo.EncodingFormat.ENCODING_PCM_16BIT)
        .channelMask(AudioStreamInfo.ChannelMask.CHANNEL_IN_STEREO)
        .streamUsage(AudioStreamInfo.StreamUsage.STREAM_USAGE_MEDIA)
        .sampleRate(SAMPLE_RATE)
        .build();
AudioCapturerInfo audioCapturerInfo = new AudioCapturerInfo.Builder().audioStreamInfo(audioStreamInfo)
        .audioInputSource(source)
        .build();
audioCapturer = new AudioCapturer(audioCapturerInfo, currentAudioType);