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service - How to record video from background of application : Android

I am developing an application which will be able to record video from background of application by using Service.

Problem description :

In my application recording will be scheduled. If user want to record video from 1 PM to 3 PM, he will schedule the task and can exit from application. Application will automatically start recording at 1PM to 3PM.

What I did yet :

I googled about my query but didn't get solution. Many articles say that it is not possible. But in Google Play there are some applications (for eg MyCar Recorder) which can record video from background of application.

I got an article about same but its not working.

What is the way to implement this functionality?

See Question&Answers more detail:os

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1 Answer

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1- I have created a activity to start service like this:

package com.android.camerarecorder;

import android.app.Activity;
import android.content.Intent;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;

public class CameraRecorder extends Activity implements SurfaceHolder.Callback {
    private static final String TAG = "Recorder";
    public static SurfaceView mSurfaceView;
    public static SurfaceHolder mSurfaceHolder;
    public static Camera mCamera ;
    public static boolean mPreviewRunning;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mSurfaceView = (SurfaceView) findViewById(R.id.surfaceView1);
        mSurfaceHolder = mSurfaceView.getHolder();
        mSurfaceHolder.addCallback(this);
        mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        Button btnStart = (Button) findViewById(R.id.StartService);
        btnStart.setOnClickListener(new View.OnClickListener()
        {
            public void onClick(View v)
            {
                Intent intent = new Intent(CameraRecorder.this, RecorderService.class);
                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                startService(intent);
                finish();
            }
        });

        Button btnStop = (Button) findViewById(R.id.StopService);
        btnStop.setOnClickListener(new View.OnClickListener()
        {
            public void onClick(View v)
            {
                stopService(new Intent(CameraRecorder.this, RecorderService.class));
            }
        });
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {

    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        // TODO Auto-generated method stub

    }
}

2 - Now I have created a service to record the video in background like this:

    package com.android.camerarecorder;
    import java.io.IOException;
    import java.util.List;
    import android.app.Service;
    import android.content.Intent;
    import android.graphics.PixelFormat;
    import android.hardware.Camera;
    import android.hardware.Camera.Size;
    import android.media.MediaRecorder;
    import android.os.IBinder;
    import android.util.Log;
    import android.view.SurfaceHolder;
    import android.view.SurfaceView;
    import android.widget.Toast;

    public class RecorderService extends Service {
        private static final String TAG = "RecorderService";
        private SurfaceView mSurfaceView;
        private SurfaceHolder mSurfaceHolder;
        private static Camera mServiceCamera;
        private boolean mRecordingStatus;
        private MediaRecorder mMediaRecorder;

        @Override
        public void onCreate() {
            mRecordingStatus = false;
            //mServiceCamera = CameraRecorder.mCamera;
            mServiceCamera = Camera.open(1);
            mSurfaceView = CameraRecorder.mSurfaceView;
            mSurfaceHolder = CameraRecorder.mSurfaceHolder;

            super.onCreate();
            if (mRecordingStatus == false)
                startRecording();
        }

        @Override
        public IBinder onBind(Intent intent) {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public void onDestroy() {
            stopRecording();
            mRecordingStatus = false;

            super.onDestroy();
        }   

        public boolean startRecording(){
            try {
                Toast.makeText(getBaseContext(), "Recording Started", Toast.LENGTH_SHORT).show();

                //mServiceCamera = Camera.open();
                Camera.Parameters params = mServiceCamera.getParameters();
                mServiceCamera.setParameters(params);
                Camera.Parameters p = mServiceCamera.getParameters();

                final List<Size> listSize = p.getSupportedPreviewSizes();
                Size mPreviewSize = listSize.get(2);
                Log.v(TAG, "use: width = " + mPreviewSize.width 
                            + " height = " + mPreviewSize.height);
                p.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
                p.setPreviewFormat(PixelFormat.YCbCr_420_SP);
                mServiceCamera.setParameters(p);

                try {
                    mServiceCamera.setPreviewDisplay(mSurfaceHolder);
                    mServiceCamera.startPreview();
                }
                catch (IOException e) {
                    Log.e(TAG, e.getMessage());
                    e.printStackTrace();
                }

                mServiceCamera.unlock();

                mMediaRecorder = new MediaRecorder();
                mMediaRecorder.setCamera(mServiceCamera);
                mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
                mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
                mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
                mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
                mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT);
                mMediaRecorder.setOutputFile("/sdcard/video.mp4");
                mMediaRecorder.setVideoFrameRate(30);
                mMediaRecorder.setVideoSize(mPreviewSize.width, mPreviewSize.height);
                mMediaRecorder.setPreviewDisplay(mSurfaceHolder.getSurface());

                mMediaRecorder.prepare();
                mMediaRecorder.start(); 

                mRecordingStatus = true;

                return true;
            } catch (IllegalStateException e) {
                Log.d(TAG, e.getMessage());
                e.printStackTrace();
                return false;
            } catch (IOException e) {
                Log.d(TAG, e.getMessage());
                e.printStackTrace();
                return false;
            }
        }

        public void stopRecording() {
            Toast.makeText(getBaseContext(), "Recording Stopped", Toast.LENGTH_SHORT).show();
            try {
                mServiceCamera.reconnect();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            mMediaRecorder.stop();
            mMediaRecorder.reset();

            mServiceCamera.stopPreview();
            mMediaRecorder.release();

            mServiceCamera.release();
            mServiceCamera = null;
        }
    }

It will create a file video.mp4 in your sd card. you may change the code for adding more functionality but the basic functionality is achieved through this code i.e. record video in background.

NOTE: i have started the service through button click in activity but you can start it through any other way also like broadcastreceiver etc.

Hope it helps!! Cheers.


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