I try to build a custom video recording app and followed a tutorial on the internet. However I get the problem that the screen goes to black after pressing the start button and nothing else happened. After pressing stop button, I checked the directory where I put the output video. It is there but the size is 0 KB.
I used a surfaceview and here is the xml layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<Button
android:id="@+id/start"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="- Start Camera Preview -"
/>
<Button
android:id="@+id/stop"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="- Stop Camera Preview -"
/>
<SurfaceView
android:id="@+id/surfaceview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
And here is brief code for recording video:
public class CamTestActivity extends Activity implements SurfaceHolder.Callback{
private static final String TAG = "Camera-Tutorial";
private SurfaceView surfaceView;
private SurfaceHolder surfaceHolder;
private Camera camera;
private boolean previewRunning;
private int VIDEO_TYPE = 3;
private int intVideoIndex = 1;
private MediaRecorder mediaRecorder;
private final int maxDurationInMs = 20000;
private final int videoFramesPerSecond = 20;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.videopreview);
// setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
surfaceView = (SurfaceView) findViewById(R.id.surfaceview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
Button start_video = (Button) findViewById(R.id.start);
Button stop_video = (Button) findViewById(R.id.stop);
stop_video.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
mediaRecorder.stop();
camera.lock();
}
});
start_video.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
try {
camera.unlock();
mediaRecorder = new MediaRecorder();
mediaRecorder.setCamera(camera);
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
mediaRecorder.setOutputFile(GetOutputMediaFileDir(VIDEO_TYPE,intVideoIndex));
mediaRecorder.setVideoFrameRate(1);
mediaRecorder.setVideoEncoder(MediaRecorder.AudioEncoder.AAC);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
mediaRecorder.prepare();
mediaRecorder.start();
} catch (IllegalStateException e) {
Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_LONG).show();
// Log.e(TAG,e.getMessage());
// e.printStackTrace();
} catch (IOException e) {
Log.e(TAG,e.getMessage());
// e.printStackTrace();
}
}
});
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
camera = Camera.open();
if (camera != null){
Camera.Parameters params = camera.getParameters();
camera.setParameters(params);
}
else {
Toast.makeText(getApplicationContext(), "Camera not available!", Toast.LENGTH_LONG).show();
finish();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
if (previewRunning){
camera.stopPreview();
}
Camera.Parameters p = camera.getParameters();
p.setPreviewSize(width, height);
camera.setParameters(p);
try {
camera.setPreviewDisplay(holder);
camera.startPreview();
previewRunning = true;
}
catch (IOException e) {
Log.e(TAG,e.getMessage());
e.printStackTrace();
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
camera.stopPreview();
previewRunning = false;
camera.release();
}
public static String GetOutputMediaFileDir(int fileType, int index){
String fileDir=null;
String strIndex = Integer.toString(index);
if(fileType == 1)
{
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_MUSIC), "Audio");
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
fileDir = mediaStorageDir.getPath() + File.separator +
"AUDIO_"+ strIndex + ".mp4";
}
if(fileType == 2)
{
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "Image");
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
fileDir = mediaStorageDir.getPath() + File.separator +
"IMAGE_"+ strIndex + ".jpeg";
}
if(fileType == 3)
{
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_MOVIES), "Video");
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
fileDir = mediaStorageDir.getPath() + File.separator +
"VIDEO_"+ strIndex + ".mp4";
}
return fileDir;
}
}
Any ideas of how to solve the problem? Thanks a lot in advance.
Changes that solve the problem:
Firstly I set the video encoder to an audio encoder, this should be changed;
Secondly mediaRecorder.setPreviewDisplay(surfaceView.getHolder().getSurface()); should be added beforemediaRecorder.prepare()
Then it works properly.
