tests/Camera2Tests/SmartCamera/SimpleCamera/src/androidx/media/filterfw/MotionSensor.java

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * 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.
 */

// Make values from a motion sensor (e.g., accelerometer) available as filter outputs.

package androidx.media.filterpacks.sensors;

import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;

import androidx.media.filterfw.Filter;
import androidx.media.filterfw.FrameType;
import androidx.media.filterfw.FrameValues;
import androidx.media.filterfw.MffContext;
import androidx.media.filterfw.OutputPort;
import androidx.media.filterfw.Signature;

public final class MotionSensor extends Filter implements SensorEventListener {

    private SensorManager mSensorManager = null;
    private Sensor mSensor = null;

    private float[] mValues = new float[3];

    public MotionSensor(MffContext context, String name) {
        super(context, name);
    }

    @Override
    public Signature getSignature() {
        return new Signature()
            .addOutputPort("values", Signature.PORT_REQUIRED, FrameType.array(float.class))
            .disallowOtherPorts();
    }

    @Override
    protected void onPrepare() {
        mSensorManager = (SensorManager)getContext().getApplicationContext()
                            .getSystemService(Context.SENSOR_SERVICE);
        mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_LINEAR_ACCELERATION);
        // TODO: currently, the type of sensor is hardcoded. Should be able to set the sensor
        //  type as filter input!
        mSensorManager.registerListener(this, mSensor, SensorManager.SENSOR_DELAY_UI);
    }

    @Override
    protected void onTearDown() {
        mSensorManager.unregisterListener(this);
    }

    @Override
    public final void onAccuracyChanged(Sensor sensor, int accuracy) {
        // (Do we need to do something when sensor accuracy changes?)
    }

    @Override
    public final void onSensorChanged(SensorEvent event) {
        synchronized(mValues) {
            mValues[0] = event.values[0];
            mValues[1] = event.values[1];
            mValues[2] = event.values[2];
        }
    }

    @Override
    protected void onProcess() {
        OutputPort outPort = getConnectedOutputPort("values");
        FrameValues outFrame = outPort.fetchAvailableFrame(null).asFrameValues();
        synchronized(mValues) {
            outFrame.setValues(mValues);
        }
        outFrame.setTimestamp(System.currentTimeMillis() * 1000000L);
        outPort.pushFrame(outFrame);
    }
}