Use MediaRecorder to record video files
Android emulator cannot record audio.
Life cycle
First, you need to grant two permissions through ActivityCompat.requestPermissions():
<uses-permission android:name="android.permission.CAMERA" /> <uses-permission android:name="android.permission.RECORD_AUDIO" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
The steps to record audio using MediaRecorder are usually as follows:
MediaRecorder recorder = new MediaRecorder(); recorder.setAudioSource(MediaRecorder.AudioSource.MIC); recorder.setVideoSource(MediaRecorder.VideoSource.CAMERA); recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP); recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB); recorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264); recorder.setOutputFile(PATH_NAME); recorder.prepare(); recorder.start(); // Recording is now started ... recorder.stop(); recorder.reset(); // You can reuse the object by going back to setAudioSource() step recorder.release(); // Now the object cannot be reused // Remember to release camera resources
Code
Detailed steps for recording videos with Android MediaRecorder_APDL_10’s Blog-CSDN Blog
GitHub – android/media-samples at master
There are many demo examples in this
The way these codes are written is really interesting, gives people a good feeling, and is worth learning.
After clicking the record button, determine whether to enter the recording state or end the recording based on the current status.
Because recording needs to be prepared first and then started, go to the prepare sub-method first to enter the relevant initialization configuration, and then decide whether to start based on the return value of prepare (these two steps are executed through async)
If the end is entered, the resources are released.
When setting a series of parameters such as audio and video encoder, output format, bit rate, etc., you can actually use the setProfile method to set them, instead of setting them one by one.
public class MediaRecorderActivity extends AppCompatActivity {
private static final String TAG = "MediaRecorderActivity";
private Camera mCamera;
private SurfaceView mPreview;
private MediaRecorder mMediaRecorder;
private File mOutputFile;
private boolean isRecording = false;
private Button captureButton;
public static Intent newIntent(Context packageContext) {
Intent intent = new Intent(packageContext, MediaRecorderActivity.class);
return intent;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_media_recorder);
mPreview = findViewById(R.id.afv_media_recorder);
captureButton = findViewById(R.id.btn_media_recorder_capture);
}
/**
* The capture button controls all user interaction. When recording, the button click
* stops recording, releases {@link android.media.MediaRecorder} and
* {@link android.hardware.Camera}. When not recording, it prepares the
* {@link android.media.MediaRecorder} and starts recording.
*
* @param view the view generating the event.
*/
public void onCaptureClick(View view) {
if (isRecording) {
// BEGIN_INCLUDE(stop_release_media_recorder)
// stop recording and release camera
try {
mMediaRecorder.stop(); // stop the recording
} catch (RuntimeException e) {
// RuntimeException is thrown when stop() is called immediately after start().
// In this case the output file is not properly constructed ans should be deleted.
Log.d(TAG, "RuntimeException: stop() is called immediately after start()");
//noinspection ResultOfMethodCallIgnored
mOutputFile.delete();
}
releaseMediaRecorder(); // release the MediaRecorder object
mCamera.lock(); // take camera access back from MediaRecorder
// inform the user that recording has stopped
setCaptureButtonText("Capture");
isRecording = false;
releaseCamera();
// END_INCLUDE(stop_release_media_recorder)
} else {
// BEGIN_INCLUDE(prepare_start_media_recorder)
new MediaPrepareTask().execute(null, null, null);
// END_INCLUDE(prepare_start_media_recorder)
}
}
private void setCaptureButtonText(String title) {
captureButton.setText(title);
}
@Override
protected void onPause() {
super.onPause();
// if we are using MediaRecorder, release it first
releaseMediaRecorder();
// release the camera immediately on pause event
releaseCamera();
}
private void releaseMediaRecorder() {
if (mMediaRecorder != null) {
// clear recorder configuration
mMediaRecorder.reset();
// release the recorder object
mMediaRecorder.release();
mMediaRecorder = null;
// Lock camera for later use i.e taking it back from MediaRecorder.
// MediaRecorder doesn't need it anymore and we will release it if the activity pauses.
mCamera.lock();
}
}
private void releaseCamera() {
if (mCamera != null) {
// release the camera for other applications
mCamera.release();
mCamera = null;
}
}
private boolean prepareVideoRecorder() {
//1.Create recorder object
mMediaRecorder = new MediaRecorder();
//2.Set the direction of recording video
mCamera = Camera.open();//Camera object
mCamera.setDisplayOrientation(90);//Adjust the angle of the camera preview
mCamera.unlock();
mMediaRecorder.setCamera(mCamera);
//3.Set the audio source (MIC: microphone collects audio)
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
//4. Set the video source (CAMERA: camera captures video)
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
//5.Set video output format (MP4)
mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
//6.Set audio encoding format
mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
//7.Set video encoding format
mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
//8.Set the direction of video playback
mMediaRecorder.setOrientationHint(90);
//9.Set the location of the output file
// Step 4: Set output file
mOutputFile = CameraHelper.getOutputMediaFile(CameraHelper.MEDIA_TYPE_VIDEO);
if (mOutputFile == null) {
return false;
}
mMediaRecorder.setOutputFile(mOutputFile.getPath());
// END_INCLUDE (configure_media_recorder)
//10.Set the size of the output video
mMediaRecorder.setVideoSize(640,480);
//11.Set the frame rate of the video
mMediaRecorder.setVideoFrameRate(30);
//12. Set the preview interface (set a Surface, which is the preview page, and then hand it over)
mMediaRecorder.setPreviewDisplay(mPreview.getHolder().getSurface());
// Step 5: Prepare configured MediaRecorder
try {
mMediaRecorder.prepare();
} catch (IllegalStateException e) {
Log.d(TAG, "IllegalStateException preparing MediaRecorder: " + e.getMessage());
releaseMediaRecorder();
return false;
} catch (IOException e) {
Log.d(TAG, "IOException preparing MediaRecorder: " + e.getMessage());
releaseMediaRecorder();
return false;
}
return true;
}
/**
* Asynchronous task for preparing the {@link android.media.MediaRecorder} since it's a long blocking
* operation.
*/
class MediaPrepareTask extends AsyncTask<Void, Void, Boolean> {
@Override
protected Boolean doInBackground(Void... voids) {
// initialize video camera
if (prepareVideoRecorder()) {
// Camera is available and unlocked, MediaRecorder is prepared,
// now you can start recording
mMediaRecorder.start();
isRecording = true;
} else {
// prepare didn't work, release the camera
releaseMediaRecorder();
return false;
}
return true;
}
@Override
protected void onPostExecute(Boolean result) {
if (!result) {
MediaRecorderActivity.this.finish();
}
// inform the user that recording has started
setCaptureButtonText("Stop");
}
}
}