This document discusses various techniques for working with multimedia in Android applications, including detecting device capabilities, loading images from local storage and remote URLs, playing audio files from assets and raw resources, and improving performance through caching and asynchronous loading. It provides code examples for checking if a device has a front-facing camera, loading images while avoiding out of memory errors, playing audio files from assets, and using an AsyncTask to load images asynchronously to avoid blocking the UI. It also discusses potential memory leak issues and strategies for building an image cache.

1. INTERMEDIATE
ANDROID
Michael Galpin
Bump Technologies

2. ABOUT: ME
‣ Android engineer, Bump Technologies
‣ ex-eBay: eBay Mobile for Android
‣ Android in Practice
‣ Social info
‣ @michaelg
‣ +Michael Galpin

3. Bump
Technologies
• Creators of Bump app
• Android + iOS
• 65M+ Downloads
• Creators of BumpCube
• Hiring!

4. You down with AIP?
• Chapter 11: “Appeal to
the senses using
multimedia.”
• Slideshow app
MediaMogul.apk
• http://
code.google.com/p/
android-in-practice/

6. MULTIMEDIA

7. “Of all of our inventions for mass
communication, pictures still speak the
most universally understood language.”
-- Walt Disney

12. DETECTING
CAPABILITIES

14. AndroidManifest.xml
<uses-feature android:name="android.hardware.camera"
android:required="true" />
<uses-feature android:name="android.hardware.camera.autofocus"
android:required="true"/>
<uses-feature android:name="android.hardware.camera.flash"
android:required="false" />
<uses-feature android:name="android.hardware.camera.front"
android:required="false" />
<uses-feature android:name="android.hardware.microphone"
android:required="true"/>
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />

15. Check the front
private boolean hasFrontFacingCamera(){
PackageManager mgr = this.getPackageManager();
for (FeatureInfo fi : mgr.getSystemAvailableFeatures()){
if (fi.name.equals(PackageManager.FEATURE_CAMERA_FRONT)){
return true;
}
}
return false;
}
private Camera getFrontFacingCamera(){
for (int i=0;i<Camera.getNumberOfCameras();i++){
Camera.CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(i, info);
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT){
return Camera.open(i);
}
}
return null;
}

16. Check the front
private boolean hasFrontFacingCamera(){
PackageManager mgr = this.getPackageManager();
for (FeatureInfo fi : mgr.getSystemAvailableFeatures()){
if (fi.name.equals(PackageManager.FEATURE_CAMERA_FRONT)){
return true;
}
}
return false;
}
private Camera getFrontFacingCamera(){
for (int i=0;i<Camera.getNumberOfCameras();i++){
Camera.CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(i, info);
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT){
return Camera.open(i);
}
}
return null;
}

17. But I have to
support
Android 2.1

20. Reflection?

21. LOLZ
// Can't use Build.VERSION_CODES.GINGERBREAD
if (Build.VERSION.SDK_INT >= 9){
PostFroyoClass wontThisBlowUp = new PostFroyoClass();
}

22. These are my customers!

23. These are my customers!

24. Proprietary APIs FTW!
import com.sprint.hardware.twinCamDevice.FrontFacingCamera;
Camera evoCam = FrontFacingCamera.getFrontFacingCamera();

25. RESOURCES

27. MediaPlayer.framework?

28. MediaPlayer.framework?
[MPMusicPlayerController iPodMusicPlayer] ??

29. MediaPlayer.framework?
[MPMusicPlayerController iPodMusicPlayer] ??
[MusicLibrary sharedMusicLibrary] ???

30. MediaPlayer.framework?
[MPMusicPlayerController iPodMusicPlayer] ??
[MusicLibrary sharedMusicLibrary] ???
UIImagePickerController ?

31. MediaPlayer.framework?
[MPMusicPlayerController iPodMusicPlayer] ??
[MusicLibrary sharedMusicLibrary] ???
UIImagePickerController ?

32. MediaPlayer.framework?
[MPMusicPlayerController iPodMusicPlayer] ??
[MusicLibrary sharedMusicLibrary] ???
UIImagePickerController ?
Files !!!!

33. Inside your APK
External

34. Just give it to me /res/raw
Resources res = this.getResources();
InputStream stream = res.openRawResource(R.raw.sunflower);
MediaPlayer.create(this, R.raw.constancy).start();

35. I like big /
assets
and I cannot lie

36. MediaPlayer player = new MediaPlayer();
AssetManager mgr = getResources().getAssets();
String audioDir = "audio";
final LinkedList<FileDescriptor> queue =
new LinkedList<FileDescriptor>();
for (String song : mgr.list("audio")){
queue.add(
mgr.openFd(audioDir + "/" + song).getFileDescriptor());
}
if (!queue.isEmpty()){
FileDescriptor song = queue.poll();
player.setDataSource(song);
player.prepare();
player.start();
}
player.setOnCompletionListener(new OnCompletionListener(){
@Override
public void onCompletion(MediaPlayer mp) {
if (!queue.isEmpty()){
FileDescriptor song = queue.poll();
player.setDataSource(song);
player.prepare();
player.start();
}
}
});

38. File picturesDir =
Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES);

39. File picturesDir =
Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES);

40. IMAGES

42. Loading local images
InputStream stream = new FileInputStream(imgFile);
Bitmap bm = BitmapFactory.decodeStream(stream);

43. Loading local images
InputStream stream = new FileInputStream(imgFile);
Bitmap bm = BitmapFactory.decodeStream(stream);
// calculate desired width and height
Bitmap thumb = ThumbnailUtils.extractThumbnail(bm, width, height);
Bitmap thumb = Bitmap.createScaledBitmap(bm, width, height, false);

45. Loading without
exploding
public static Bitmap decodeDownsizedBitmapStream(File file, int target, Context context) throws
IOException {
FileInputStream stream = new FileInputStream(file);
Pair<Integer, Integer> source = getDimensionsForStream(stream);
stream.close();
FileInputStream in = new FileInputStream(file);
Options options = new Options();
options.inSampleSize = 1 + getDownSampleSize(max(source.first, source.second), target);
return BitmapFactory.decodeStream(in, null, options);
}
public static Pair<Integer, Integer> getDimensionsForStream(InputStream in){
Options options = new Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(in, null, options);
return new Pair<Integer, Integer>(options.outWidth, options.outHeight);
}
public static int getDownSampleSize(int source, int target){
int size = 1;
if (source <= 2*target){
int power = (int) ((log (source / target)) / log(2));
size = (int) pow(2, power);
}
return size;
}

46. Loading web images
URL url = new URL(urlString);
// NOTE, be careful about just doing "url.openStream()"
// it's a shortcut for openConnection().getInputStream() and doesn't set timeouts
// the defaults are "infinite" so it will wait forever if endpoint server is down
// do it properly with a few more lines of code . . .
URLConnection conn = url.openConnection();
conn.setConnectTimeout(3000);
conn.setReadTimeout(5000);
Bitmap bitmap = BitmapFactory.decodeStream(conn.getInputStream());

48. AsyncTask FTW!
private class RetrieveImageTask extends AsyncTask<String, Void, Bitmap> {
private ImageView imageView;
public RetrieveImageTask(ImageView imageView) {
this.imageView = imageView;
}
@Override
protected Bitmap doInBackground(String... args) {
try {
URL url = new URL(args[0]);
URLConnection conn = url.openConnection();
conn.setConnectTimeout(3000);
conn.setReadTimeout(5000);
return BitmapFactory.decodeStream(conn.getInputStream());
} catch (Exception e) {
}
return null;
}
@Override
protected void onPostExecute(Bitmap bitmap) {
if (bitmap != null) {
imageView.setImageBitmap(bitmap);
}
}
}

49. Loading a dozen images
isn’t cool.
Y’know what’s cool?
Loading a billion images.

50. Hot or Not?
private class DealsAdapter extends ArrayAdapter<Item> {
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater)
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_item, parent, false);
}
TextView text = (TextView) convertView.findViewById(R.id.deal_title);
ImageView image = (ImageView) convertView.findViewById(R.id.deal_img);
Item item = getItem(position);
if (item != null) {
text.setText(item.getTitle());
new RetrieveImageTask(image).execute(item.getSmallPicUrl());
}
return convertView;
}
}

51. Watch out for leaks
public class LeakProofActivity extends Activity {
LeakProofAsyncTask task;
private class LeakProofAsyncTask extends AsyncTask<String, Void, Bitmap>{
Context potentialLeak = LeakProofActivity.this;
@Override
protected Bitmap doInBackground(String... arg0) {
// Do something that takes a long time
// Note if you need a Context here, use Application
return null;
}
@Override
protected void onPostExecute(Bitmap result){
// update UI, etc.
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
task = (LeakProofAsyncTask) getLastNonConfigurationInstance();
if (task != null){
task.potentialLeak = this;
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if (task != null){
task.potentialLeak = null;
}
}
@Override
public Object onRetainNonConfigurationInstance() {
return task;
}
}

53. How to build a cache?
• WeakReferences?
• SoftReferences?
• WeakHashMap?
• MapMaker?

54. LinkedHashMap!?
private static class ImageCache extends LinkedHashMap<String, Bitmap>{
private final int capacity;
public ImageCache(int capacity){
super(capacity/2, 0.75f, true);
this.capacity = capacity;
}
@Override
protected boolean removeEldestEntry(Entry<String, Bitmap> eldest) {
return this.size() > capacity;
}
}

55. Disk Cache
• Context.getCacheDir()
• SQLite
• Environment.getExternalStorage()

56. Sidebar: Bitmaps & Heap
Reported by andreas....@googlemail.com, May 22, 2010
Note: This is NOT a requst for assistance!
In my applications, I keep getting the following exception:
E/AndroidRuntime( 1420): java.lang.OutOfMemoryError: bitmap size exceeds
VM budget
E/AndroidRuntime( 1420):
at
android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
E/AndroidRuntime( 1420):
at
android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:459)
E/AndroidRuntime( 1420):
at
android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:515)
E/AndroidRuntime( 1420):
at
de.schildbach.bitmapbug.MyActivity.bitmap(MyActivity.java:38)
Comment 1 by romaingu...@gtempaccount.com, May 23, 2010
Your app needs to use less memory.
http://code.google.com/p/android/issues/detail?id=8488

58. Use Placeholders
ImageView image =
(ImageView) convertView.findViewById(R.id.deal_img);
image.setImageBitmap(
BitmapFactory.decodeResource(
getResources(), R.drawable.temp));
Item item = getItem(position);
new RetrieveImageTask(image).
execute(item.getSmallPicUrl());

59. @Override
View Holders
public View getView(final int position, View cell, ViewGroup parent) {
ViewHolder holder = (ViewHolder) cell.getTag();
if (holder == null){
holder = new ViewHolder(cell);
cell.setTag(holder);
}
Bitmap thumb = (Bitmap) getItem(position);
holder.img.setImageBitmap(thumb);
File file = getImageFile(position);
if (selectedFiles.contains(file)){
holder.cbox.setChecked(true);
} else {
holder.cbox.setChecked(false);
}
return cell;
}
static class ViewHolder {
final ImageView img;
final CheckBox cbox;
ViewHolder(View cell){
img = (ImageView) cell.findViewById(R.id.thumb);
cbox = (CheckBox) cell.findViewById(R.id.cbox);
}
}

60. Sidebar: Strict Mode

61. CONTENT
PROVIDERS

62. SQL?
NoSQL?
SortOfSQL!

63. Queries
Cursor cursor = getContentResolver().query(table,
columns,
whereClause,
paramValues,
sortOrder);
while (cursor.moveToNext()){
// process results
}
cursor.close();

64. Music
import static android.provider.BaseColumns._ID;
import static android.provider.MediaStore.Audio.AudioColumns.ARTIST;
import static android.provider.MediaStore.Audio.AudioColumns.IS_MUSIC;
import static android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
import static android.provider.MediaStore.MediaColumns.DATA;
import static android.provider.MediaStore.MediaColumns.TITLE;
String[] columns = {TITLE,ARTIST,_ID, DATA};
// where clause so we don't get ringtones, podcasts, etc.
String whereClause = IS_MUSIC + " = ?";
String[] whereValues = {"1"};
cursor = managedQuery(EXTERNAL_CONTENT_URI,
columns,
whereClause,
whereValues,
null
);

65. Contacts
String[] projection = {Phone.CONTACT_ID, Phone.NUMBER};
String selection = Data.IN_VISIBLE_GROUP + "=1 AND " +
Phone.NUMBER + " LIKE ?";
String[] selectionArgs = {"%" + phoneSubStr + "%"};
Cursor phoneCursor = resolver.query(Phone.CONTENT_URI,
projection,
selection,
selectionArgs,
null);
String[] projection = new String[] {StructuredName.GIVEN_NAME,
StructuredName.FAMILY_NAME,
StructuredName.RAW_CONTACT_ID,
StructuredName.CONTACT_ID};
String selection = StructuredName.CONTACT_ID+ " = ? AND " +
Data.MIMETYPE + " = '" + StructuredName.CONTENT_ITEM_TYPE +"'";
String[] selectionArgs = new String[] {contact.id};
Cursor nameCursor = resolver.query(Data.CONTENT_URI,
projection,
selection,
selectionArgs,
null);

67. Scanning media

68. Scanning 101
MediaScannerConnection conn = new MediaScannerConnection(this,
new MediaScannerConnectionClient(){
public void onMediaScannerConnected(){
scanFile("/some/path/SomeSong.mp3", "audio/mpeg3");
scanFile("/some/other/path/IMG1999.jpg", "image/jpeg");
}
public void onScanCompleted(String path, Uri uri){
Log.d("LogTag", "Media scanned uir=" + uri.toString());
}
});
conn.connect();

69. Cursor Adapter

70. CursorAdapter

71. Avoid

72. Use Other Apps
private static final int SELECT_VIDEO = 1;
private Uri videoUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
Button vidBtn = (Button) findViewById(R.id.vidBtn);
vidBtn.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View button) {
Intent videoChooser = new Intent(Intent.ACTION_GET_CONTENT);
videoChooser.setType("video/*");
startActivityForResult(videoChooser, SELECT_VIDEO);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode,
Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == SELECT_VIDEO && resultCode == RESULT_OK){
videoUri = data.getData();
}
}

74. ANIMATION

75. Dissolve Animation
private void nextSlide() {
AlphaAnimation animation = new AlphaAnimation(0.0f, 1.0f);
if ((count % 2) == 0) {
animation = new AlphaAnimation(1.0f, 0.0f);
}
animation.setStartOffset(TIME_PER_SLIDE);
animation.setDuration(TIME_PER_SLIDE);
animation.setFillAfter(true);
animation.setAnimationListener(new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {}
@Override
public void onAnimationRepeat(Animation animation) {}
@Override
public void onAnimationEnd(Animation animation) {
if (playingSlides){
nextImage = getNextImage();
ImageView backgroundImage =
(count % 2 == 0) ? rightSlide : leftSlide;
backgroundImage.setImageBitmap(nextImage);
count++;
nextSlide();
}
}
});
rightSlide.startAnimation(animation);
currentImage = nextImage;
}

76. Honeycomb+

77. Animators
ImageView backgroundImage = (count % 2 == 0) ? rightSlide : leftSlide;
ObjectAnimator anim =
ObjectAnimator.ofFloat(backgroundImage, "alpha", 0.0f, 1.0f);
anim.addListener(new AnimatorListenerAdapter(){
public void onAnimationEnd(Animator animator){
nextSlide();
}
});

80. A/V
PLAYBACK

81. playBtn.setOnClickListener(new OnClickListener(){
private Handler handler = new Handler();
MediaPlayer player = null;
long maxTime = 15L*1000; // 15 seconds
long timeLeft = maxTime;
Audio Preview
Runnable autoStop;
@Override
public void onClick(View view) {
if (player == null){
player = MediaPlayer.create(activity, song.uri);
}
if (!playingSongs.contains(song.id)){ Start/Resume
player.start();
playingSongs.add(song.id);
autoStop = new Runnable(){
Timer
@Override
public void run() {
player.pause();
player.seekTo(0);
playingSongs.remove(song.id);
playBtn.setText(R.string.play);
timeLeft = maxTime;
}
};
handler.postDelayed(autoStop, timeLeft);
playBtn.setText(R.string.pause);
} else {
player.pause();
Pause
playingSongs.remove(song.id);
timeLeft = maxTime - player.getCurrentPosition();
playBtn.setText(R.string.play);
Calc time left
handler.removeCallbacks(autoStop);
}
}
});

82. Handler?

83. Handler?
Pipeline Thread
Looper.prepare();
handler = new Handler();
// handle tasks in queue
Looper.loop();

84. Handler?
Thread Pipeline Thread
Looper.prepare();
handler = new Handler();
// handle tasks in queue
Looper.loop();
// long running task
Message msg =
handler.obtainMessage();
handler.sendMessage(msg);

85. Handler?
Thread Pipeline Thread Thread
Looper.prepare();
handler = new Handler();
// handle tasks in queue
// long running task
handler.post(
Looper.loop(); new Runnable() {...
});
// long running task
Message msg =
handler.obtainMessage();
handler.sendMessage(msg);

86. Theme Muzak
private MediaPlayer player;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setupThemeMusic();
}
@Override
public void onResume() {
super.onResume();
if (player != null){
player.start();
}
@Override
}
public void onPause(){
super.onPause();
if (player != null && player.isPlaying()){
player.pause();
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if (player != null && player.isPlaying()){
player.stop();
}
player.release();
}

87. Activity Lifecycle

89. Video Playback
Uri videoUri = ...;
VideoView video = (VideoView) findViewById(R.id.video);
video.setVideoURI(videoUri);
MediaController controller = new MediaController(this);
controller.setMediaPlayer(video);
video.setMediaController(controller);
video.requestFocus();
video.start();

91. TAKE A
PICTURE

92. Use the Camera (app)
import static android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
photoUri = getContentResolver().insert(
EXTERNAL_CONTENT_URI, new ContentValues());
intent.putExtra(MediaStore.EXTRA_OUTPUT, photoUri);
startActivityForResult(intent,TAKE_PHOTO);
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK && requestCode == TAKE_PHOTO){
ImageView img = (ImageView) findViewById(R.id.photoThumb);
InputStream stream =
getContentResolver().openInputStream(photoUri);
Bitmap bmp = BitmapFactory.decodeStream(stream);
img.setImageBitmap(bmp);
}
}

94. EXIF!

95. Popular on Facebook

96. Correctly Oriented
Options photoImageOptions = new BitmapFactory.Options();
Matrix matrix = new Matrix();
ExifInterface ei = new ExifInterface(somePath);
int orientation = ei.getAttributeInt(TAG_ORIENTATION, ORIENTATION_UNDEFINED);
int angle = 0;
switch (orientation) {
case ORIENTATION_ROTATE_90 : angle=90; break;
case ORIENTATION_ROTATE_180 : angle=180; break;
case ORIENTATION_ROTATE_270 : angle=270; break;
default: break;
}
Bitmap bm = BitmapFactory.decodeFile(path, photoImageOptions);
if (angle > 0){
matrix.setRotate(angle);
Bitmap bm = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(),
matrix, true);
}

97. Geo Tagging
ExifInterface exif = new ExifInterface(filename);
exif.setAttribute(ExifInterface.TAG_GPS_LATITUDE, latitude);
exif.setAttribute(ExifInterface.TAG_GPS_LONGITUDE, longitude);
exif.saveAttributes();
“dd/1,mm/1,ss/1”

98. Where?

99. Getting a (geo) fix
LocationManager mgr = getSystemService(LOCATION_SERVICE);
for (String provider : mgr.getAllProviders()){
Location last = mgr.getLastKnownLocation(last);
mgr.requestLocationUpdates(provider, 60000, 500, new LocationListener(){
public void onLocationChanged(Location loc){
// do stuff
}
// other methods
});
}

100. To the cloud!

101. Uploading a photo
String url = "http://my/server";
HttpClient client = new DefaultHttpClient();
HttpContext context = new BasicHttpContext();
HttpPost post = new HttpPost(url);
File imgFile = new File("/path/to/my/image");
MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
entity.addPart("image", new FileBody(imgFile));
post.setEntity(entity);
HttpResponse response = client.execute(httpPost, localContext);

103. Upload Service
UploadService extends IntentService {
protected void onHandleIntent(Intent i){
String imgPath = i.getStringExtra("file");
// upload code goes here
}
}
Intent i = new Intent(this, UploadService.class);
i.putExtra("file", "/path/to/my/image");
startService(i);

105. Process Priority
Foreground
Visible
Service
Background
Empty

106. A/V
RECORDING

108. Video Preview
private SurfaceHolder holder;
private Camera camera;
private MediaRecorder mediaRecorder;
private File tempFile;
private SurfaceView preview;
private boolean isRecording = false;
private final int maxDurationInMs = 20000;
private final long maxFileSizeInBytes = 500000;
private final int videoFramesPerSecond = 20;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
preview = new SurfaceView(this);
holder = preview.getHolder();
holder.addCallback(cameraman);
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
setContentView(preview);
tempFile = new File(getCacheDir(), "temp.mov");
if (tempFile.length() > 0){
tempFile.delete();
}
}

109. Video Preview
private Callback cameraman = new Callback(){
@Override
public void surfaceCreated(SurfaceHolder holder) {
camera = Camera.open();
camera.setPreviewDisplay(holder);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format,
int width,int height) {
Parameters params = camera.getParameters();
List<Size> sizes = params.getSupportedPreviewSizes();
Size optimalSize = getOptimalPreviewSize(sizes, width, height);
params.setPreviewSize(optimalSize.width, optimalSize.height);
camera.setParameters(params);
camera.startPreview();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
camera.stopPreview();
camera.release();
}
};

110. Video Preview
private void startRecording(){
if (isRecording){
return;
}
isRecording = true;
camera.unlock();
mediaRecorder = new MediaRecorder();
mediaRecorder.setCamera(camera);
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
mediaRecorder.setMaxDuration(maxDurationInMs);
mediaRecorder.setOutputFile(tempFile.getPath());
mediaRecorder.setVideoFrameRate(videoFramesPerSecond);
mediaRecorder.setVideoSize(preview.getWidth(), preview.getHeight());
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
mediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT);
mediaRecorder.setPreviewDisplay(holder.getSurface());
mediaRecorder.setMaxFileSize(maxFileSizeInBytes);
mediaRecorder.prepare();
mediaRecorder.start();
}