AWARE: Ambient Noise

Ambient Noise sensor allows us to collect ambient noise information by each period using a phone's microphone. The data contains RMS, frequency (Hz), and decibels(dB). As an audio processing unit, this sensor uses EZAudio which is an open-source audio sensing framework (MIT License).

Requirements

iOS 10 or later

Installation

com.aware.ios.sensor.ambientnoise is available through CocoaPods.

To install it, simply add the following line to your Podfile:

pod 'com.awareframework.ios.sensor.ambientnoise'

com_aware_ios_sensor_ambientnoise library into your source code.

import com_awareframework_ios_sensor_ambientnoise

Add NSMicrophoneUsageDescription into Info.plist

Public functions

AmbientNoiseSensor

init(config:AmbientNoiseSensor.Config?) : Initializes the ambient noise sensor with the optional configuration.
start(): Starts the ambient noise sensor with the optional configuration.
stop(): Stops the service.

AmbientNoiseSensor.Config

Class to hold the configuration of the sensor.

Fields

sensorObserver: AmbientNoiseObserver: Callback for live data updates.
interval: Int: Sampling interval in minute. (default = 5)
samples: Int : Data samples to collect per minute. (default = 30)
silenceThreshold: Double: A threshold of RMS for determining silence or not. (default = 50)
enabled: Boolean Sensor is enabled or not. (default = false)
debug: Boolean enable/disable logging to Xcode console. (default = false)
label: String Label for the data. (default = "")
deviceId: String Id of the device that will be associated with the events and the sensor. (default = "")
dbEncryptionKey Encryption key for the database. (default = null)
dbType: Engine Which db engine to use for saving data. (default = Engine.DatabaseType.NONE)
dbPath: String Path of the database. (default = "aware_ambientnoise")
dbHost: String Host for syncing the database. (default = null)

Broadcasts

Fired Broadcasts

AmbientNoiseSensor.ACTION_AWARE_AMBIENTNOISE fired when ambient noise saved data to db after the period ends.

Received Broadcasts

AmbientNoiseSensor.ACTION_AWARE_AMBIENTNOISE_START: received broadcast to start the sensor.
AmbientNoiseSensor.ACTION_AWARE_AMBIENTNOISE_STOP: received broadcast to stop the sensor.
AmbientNoiseSensor.ACTION_AWARE_AMBIENTNOISE_SYNC: received broadcast to send sync attempt to the host.
AmbientNoiseSensor.ACTION_AWARE_AMBIENTNOISE_SET_LABEL: received broadcast to set the data label. Label is expected in the AmbientNoiseSensor.EXTRA_LABEL field of the intent extras.

Data Representations

AmbientNoise Data

Contains the raw sensor data.

Field	Type	Description
frequency	Double	Sound frequency in Hz
decibels	Double	Sound decibels in dB
rms	Double	Sound RMS
isSilent	Boolean	0 = not silent 1 = is silent
silenceThreshold	Double	The used threshold when classifying between silent vs not silent
label	String	Customizable label. Useful for data calibration or traceability
deviceId	String	AWARE device UUID
label	String	Customizable label. Useful for data calibration or traceability
timestamp	Int64	unixtime milliseconds since 1970
timezone	Int	Timezone of the device
os	String	Operating system of the device (ex. ios)

Example usage

var sensor = AmbientNoiseSensor(AmbientNoiseSensor.Config().apply{config in
    config.debug = true
    config.dbType = .REALM
    config.sensorObserver = Observer()
})
sensor.start()

class Observer:AmbientNoiseObserver{
    func onAmbientNoiseChanged(data: AmbientNoiseData) {
        // code here..
    }
}

Author

Yuuki Nishiyama, yuuki.nishiyama@oulu.fi

Dependency Library

Audio sensing and processing modules are based on EZAudio which is released by MIT License.

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

awareframework / com.awareframework.ios.sensor.ambientnoise