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Android.com

Multimedia and Camera >

# Camera

## In this document

1. Considerations
2. The Basics
3. Manifest Declarations
4. Using Existing Camera Apps
   1. Image capture intent
   2. Video capture intent
   3. Receiving camera intent result
5. Building a Camera App
   1. Detecting camera hardware
   2. Accessing cameras
   3. Checking camera features
   4. Creating a preview class
   5. Placing preview in a layout
   6. Capturing pictures
   7. Capturing videos
   8. Releasing the camera
6. Saving Media Files

## Key Classes

1. `Camera`
2. `SurfaceView`
3. `MediaRecorder`
4. `Intent`

## See also

1. Camera
2. MediaRecorder
3. Data Storage

The Android framework includes support for various cameras and camera features available on devices, allowing you to capture pictures and videos in your applications. This document discusses a quick, simple approach to image and video capture and outlines an advanced approach for creating custom camera experiences for your users.

## Considerations

Before enabling your application to use cameras on Android devices, you should consider a few questions about how your app intends to use this hardware feature.

- Camera Requirement - Is the use of a camera so important to your application that you do not want your application installed on a device that does not have a camera? If so, you should declare the camera requirement in your manifest.
- Quick Picture or Customized Camera - How will your application use the camera? Are you just interested in snapping a quick picture or video clip, or will your application provide a new way to use cameras? For a getting a quick snap or clip, consider Using Existing Camera Apps. For developing a customized camera feature, check out the Building a Camera App section.
- Storage - Are the images or videos your application generates intended to be only visible to your application or shared so that other applications such as Gallery or other media and social apps can use them? Do you want the pictures and videos to be available even if your application is uninstalled? Check out the Saving Media Files section to see how to implement these options.

## The Basics

The Android framework supports capturing images and video through the `Camera` API or camera `Intent`. Here are the relevant classes:

`Camera`
  This class is the primary API for controlling device cameras. This class is used to take pictures or videos when you are building a camera application..
`SurfaceView`
  This class is used to present a live camera preview to the user.
`MediaRecorder`
  This class is used to record video from the camera.
`Intent`
  An intent action type of `MediaStore.ACTION_IMAGE_CAPTURE` or `MediaStore.ACTION_VIDEO_CAPTURE` can be used to capture images or videos without directly using the `Camera` object.

## Manifest Declarations

Before starting development on your application with the Camera API, you should make sure your manifest has the appropriate declarations to allow use of camera hardware and other related features.

- Camera Permission - Your application must request permission to use a device camera.

      <uses-permission android:name="android.permission.CAMERA" />

  Note: If you are using the camera via an intent, your application does not need to request this permission.

- Camera Features - Your application must also declare use of camera features, for example:

      <uses-feature android:name="android.hardware.camera" />

  For a list of camera features, see the manifest Features Reference.

  Adding camera features to your manifest causes Android Market to prevent your application from being installed to devices that do not include a camera or do not support the camera features you specify. For more information about using feature-based filtering with Android Market, see Android Market and Feature-Based Filtering.

  If your application can use a camera or camera feature for proper operation, but does not require it, you should specify this in the manifest by including the `android:required` attribute, and setting it to `false`:

      <uses-feature android:name="android.hardware.camera" android:required="false" />

- Storage Permission - If your application saves images or videos to the device's external storage (SD Card), you must also specify this in the manifest.

      <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

- Audio Recording Permission - For recording audio with video capture, your application must request the audio capture permission.

      <uses-permission android:name="android.permission.RECORD_AUDIO" />

## Using Existing Camera Apps

A quick way to enable taking pictures or videos in your application without a lot of extra code is to use an `Intent` to invoke an existing Android camera application. A camera intent makes a request to capture a picture or video clip through an existing camera app and then returns control back to your application. This section shows you how to capture an image or video using this technique.

The procedure for invoking a camera intent follows these general steps:

1. Compose a Camera Intent - Create an `Intent` that requests an image or video, using one of these intent types:
   - `MediaStore.ACTION_IMAGE_CAPTURE` - Intent action type for requesting an image from an existing camera application.
   - `MediaStore.ACTION_VIDEO_CAPTURE` - Intent action type for requesting a video from an existing camera application.
2. Start the Camera Intent - Use the `startActivityForResult()` method to execute the camera intent. After you start the intent, the Camera application user interface appears on the device screen and the user can take a picture or video.
3. Receive the Intent Result - Set up an `onActivityResult()` method in your application to receive the callback and data from the camera intent. When the user finishes taking a picture or video (or cancels the operation), the system calls this method.

### Image capture intent

Capturing images using a camera intent is quick way to enable your application to take pictures with minimal coding. An image capture intent can include the following extra information:

- `MediaStore.EXTRA_OUTPUT` - This setting requires a `Uri` object specifying a path and file name where you'd like to save the picture. This setting is optional but strongly recommended. If you do not specify this value, the camera application saves the requested picture in the default location with a default name, specified in the returned intent's `Intent.getData()` field.

The following example demonstrates how to construct a image capture intent and execute it. The `getOutputMediaFileUri()` method in this example refers to the sample code shown in Saving Media Files.

    private static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 100;
    private Uri fileUri;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // create Intent to take a picture and return control to the calling application
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

        fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE); // create a file to save the image
        intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // set the image file name

        // start the image capture Intent
        startActivityForResult(intent, CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE);
    }

When the `startActivityForResult()` method is executed, users see a camera application interface. After the user finishes taking a picture (or cancels the operation), the user interface returns to your application, and you must intercept the `onActivityResult()` method to receive the result of the intent and continue your application execution. For information on how to receive the completed intent, see Receiving Camera Intent Result.

### Video capture intent

Capturing video using a camera intent is a quick way to enable your application to take videos with minimal coding. A video capture intent can include the following extra information:

- `MediaStore.EXTRA_OUTPUT` - This setting requires a `Uri` specifying a path and file name where you'd like to save the video. This setting is optional but strongly recommended. If you do not specify this value, the Camera application saves the requested video in the default location with a default name, specified in the returned intent's `Intent.getData()` field.
- `MediaStore.EXTRA_VIDEO_QUALITY` - This value can be 0 for lowest quality and smallest file size or 1 for highest quality and larger file size.
- `MediaStore.EXTRA_DURATION_LIMIT` - Set this value to limit the length, in seconds, of the video being captured.
- `MediaStore.EXTRA_SIZE_LIMIT` - Set this value to limit the file size, in bytes, of the video being captured.

The following example demonstrates how to construct a video capture intent and execute it. The `getOutputMediaFileUri()` method in this example refers to the sample code shown in Saving Media Files.

    private static final int CAPTURE_VIDEO_ACTIVITY_REQUEST_CODE = 200;
    private Uri fileUri;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        //create new Intent
        Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);

        fileUri = getOutputMediaFileUri(MEDIA_TYPE_VIDEO);  // create a file to save the video
        intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);  // set the image file name

        intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1); // set the video image quality to high

        // start the Video Capture Intent
        startActivityForResult(intent, CAPTURE_VIDEO_ACTIVITY_REQUEST_CODE);
    }

When the `startActivityForResult()` method is executed, users see a modified camera application interface. After the user finishes taking a video (or cancels the operation), the user interface returns to your application, and you must intercept the `onActivityResult()` method to receive the result of the intent and continue your application execution. For information on how to receive the completed intent, see the next section.

### Receiving camera intent result

Once you have constructed and executed an image or video camera intent, your application must be configured to receive the result of the intent. This section shows you how to intercept the callback from a camera intent so your application can do further processing of the captured image or video.

In order to receive the result of an intent, you must override the `onActivityResult()` in the activity that started the intent. The following example demonstrates how to override `onActivityResult()` to capture the result of the image camera intent or video camera intent examples shown in the previous sections.

    private static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 100;
    private static final int CAPTURE_VIDEO_ACTIVITY_REQUEST_CODE = 200;

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE) {
            if (resultCode == RESULT_OK) {
                // Image captured and saved to fileUri specified in the Intent
                Toast.makeText(this, "Image saved to:\n" +
                         data.getData(), Toast.LENGTH_LONG).show();
            } else if (resultCode == RESULT_CANCELED) {
                // User cancelled the image capture
            } else {
                // Image capture failed, advise user
            }
        }

        if (requestCode == CAPTURE_VIDEO_ACTIVITY_REQUEST_CODE) {
            if (resultCode == RESULT_OK) {
                // Video captured and saved to fileUri specified in the Intent
                Toast.makeText(this, "Video saved to:\n" +
                         data.getData(), Toast.LENGTH_LONG).show();
            } else if (resultCode == RESULT_CANCELED) {
                // User cancelled the video capture
            } else {
                // Video capture failed, advise user
            }
        }
    }

Once your activity receives a successful result, the captured image or video is available in the specified location for your application to access.

## Building a Camera App

Some developers may require a camera user interface that is customized to the look of their application or provides special features. Creating a customized camera activity requires more code than using an intent, but it can provide a more compelling experience for your users.

The general steps for creating a custom camera interface for your application are as follows:

- Detect and Access Camera - Create code to check for the existence of cameras and request access.
- Create a Preview Class - Create a camera preview class that extends `SurfaceView` and implements the `SurfaceHolder` interface. This class previews the live images from the camera.
- Build a Preview Layout - Once you have the camera preview class, create a view layout that incorporates the preview and the user interface controls you want.
- Setup Listeners for Capture - Connect listeners for your interface controls to start image or video capture in response to user actions, such as pressing a button.
- Capture and Save Files - Setup the code for capturing pictures or videos and saving the output.
- Release the Camera - After using the camera, your application must properly release it for use by other applications.

Camera hardware is a shared resource that must be carefully managed so your application does not collide with other applications that may also want to use it. The following sections discusses how to detect camera hardware, how to request access to a camera and how to release it when your application is done using it.

Caution: Remember to release the `Camera` object by calling the `Camera.release()` when your application is done using it! If your application does not properly release the camera, all subsequent attempts to access the camera, including those by your own application, will fail and may cause your or other applications to be shut down.

### Detecting camera hardware

If your application does not specifically require a camera using a manifest declaration, you should check to see if a camera is available at runtime. To perform this check, use the `PackageManager.hasSystemFeature()` method, as shown in the example code below:

    /** Check if this device has a camera */
    private boolean checkCameraHardware(Context context) {
        if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)){
            // this device has a camera
            return true;
        } else {
            // no camera on this device
            return false;
        }
    }

Android devices can have multiple cameras, for example a back-facing camera for photography and a front-facing camera for video calls. Android 2.3 (API Level 9) and later allows you to check the number of cameras available on a device using the `Camera.getNumberOfCameras()` method.

### Accessing cameras

If you have determined that the device on which your application is running has a camera, you must request to access it by getting an instance of `Camera` (unless you are using an intent to access the camera).

To access the primary camera, use the `Camera.open()` method and be sure to catch any exceptions, as shown in the code below:

    /** A safe way to get an instance of the Camera object. */
    public static Camera getCameraInstance(){
        Camera c = null;
        try {
            c = Camera.open(); // attempt to get a Camera instance
        }
        catch (Exception e){
            // Camera is not available (in use or does not exist)
        }
        return c; // returns null if camera is unavailable
    }

Caution: Always check for exceptions when using `Camera.open()`. Failing to check for exceptions if the camera is in use or does not exist will cause your application to be shut down by the system.

On devices running Android 2.3 (API Level 9) or higher, you can access specific cameras using `Camera.open(int)`. The example code above will access the first, back-facing camera on a device with more than one camera.

### Checking camera features

Once you obtain access to a camera, you can get further information about its capabilties using the `Camera.getParameters()` method and checking the returned `Camera.Parameters` object for supported capabilities. When using API Level 9 or higher, use the `Camera.getCameraInfo()` to determine if a camera is on the front or back of the device, and the orientation of the image.

### Creating a preview class

For users to effectively take pictures or video, they must be able to see what the device camera sees. A camera preview class is a `SurfaceView` that can display the live image data coming from a camera, so users can frame and capture a picture or video.

The following example code demonstrates how to create a basic camera preview class that can be included in a `View` layout. This class implements `SurfaceHolder.Callback` in order to capture the callback events for creating and destroying the view, which are needed for assigning the camera preview input.

    /** A basic Camera preview class */
    public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
        private SurfaceHolder mHolder;
        private Camera mCamera;

        public CameraPreview(Context context, Camera camera) {
            super(context);
            mCamera = camera;

            // Install a SurfaceHolder.Callback so we get notified when the
            // underlying surface is created and destroyed.
            mHolder = getHolder();
            mHolder.addCallback(this);
            // deprecated setting, but required on Android versions prior to 3.0
            mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }

        public void surfaceCreated(SurfaceHolder holder) {
            // The Surface has been created, now tell the camera where to draw the preview.
            try {
                mCamera.setPreviewDisplay(holder);
                mCamera.startPreview();
            } catch (IOException e) {
                Log.d(TAG, "Error setting camera preview: " + e.getMessage());
            }
        }

        public void surfaceDestroyed(SurfaceHolder holder) {
            // empty. Take care of releasing the Camera preview in your activity.
        }

        public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
            // If your preview can change or rotate, take care of those events here.
            // Make sure to stop the preview before resizing or reformatting it.

            if (mHolder.getSurface() == null){
              // preview surface does not exist
              return;
            }

            // stop preview before making changes
            try {
                mCamera.stopPreview();
            } catch (Exception e){
              // ignore: tried to stop a non-existent preview
            }

            // make any resize, rotate or reformatting changes here

            // start preview with new settings
            try {
                mCamera.setPreviewDisplay(mHolder);
                mCamera.startPreview();

            } catch (Exception e){
                Log.d(TAG, "Error starting camera preview: " + e.getMessage());
            }
        }
    }

### Placing preview in a layout

A camera preview class, such as the example shown in the previous section, must be placed in the layout of an activity along with other user interface controls for taking a picture or video. This section shows you how to build a basic layout and activity for the preview.

The following layout code provides a very basic view that can be used to display a camera preview. In this example, the `FrameLayout` element is meant to be the container for the camera preview class. This layout type is used so that additional picture information or controls can be overlayed on the live camera preview images.

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:orientation="horizontal"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        >
      <FrameLayout
        android:id="@+id/camera_preview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_weight="1"
        />

      <Button
        android:id="@+id/button_capture"
        android:text="Capture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        />
    </LinearLayout>

On most devices, the default orientation of the camera preview is landscape. This example layout specifies a horizontal (landscape) layout and the code below fixes the orientation of the application to landscape. For simplicity in rendering a camera preview, you should change your application's preview activity orientation to landscape by adding the following to your manifest.

    <activity android:name=".CameraActivity"
              android:label="@string/app_name"

              android:screenOrientation="landscape">
              <!-- configure this activity to use landscape orientation -->

              <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

Note: A camera preview does not have to be in landscape mode. Starting in Android 2.2 (API Level 8), you can use the `setDisplayOrientation()` method to set the rotation of the preview image. In order to change preview orientation as the user re-orients the phone, within the `surfaceChanged()` method of your preview class, first stop the preview with `Camera.stopPreview()` change the orientation and then start the preview again with `Camera.startPreview()`.

In the activity for your camera view, add your preview class to the `FrameLayout` element shown in the example above. Your camera activity must also ensure that it releases the camera when it is paused or shut down. The following example shows how to modify a camera activity to attach the preview class shown in Creating a preview class.

    public class CameraActivity extends Activity {

        private Camera mCamera;
        private CameraPreview mPreview;

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);

            // Create an instance of Camera
            mCamera = getCameraInstance();

            // Create our Preview view and set it as the content of our activity.
            mPreview = new CameraPreview(this, mCamera);
            FrameLayout preview = (FrameLayout) findViewById(id.camera_preview);
            preview.addView(mPreview);
        }
    }

Note: The `getCameraInstance()` method in the example above refers to the example method shown in Accessing cameras.

### Capturing pictures

Once you have built a preview class and a view layout in which to display it, you are ready to start capturing images with your application. In your application code, you must set up listeners for your user interface controls to respond to a user action by taking a picture.

In order to retrieve a picture, use the `Camera.takePicture()` method. This method takes three parameters which receive data from the camera. In order to receive data in a JPEG format, you must implement an `Camera.PictureCallback` interface to receive the image data and write it to a file. The following code shows a basic implementation of the `Camera.PictureCallback` interface to save an image received from the camera.

    private PictureCallback mPicture = new PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {

            File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE);
            if (pictureFile == null){
                Log.d(TAG, "Error creating media file, check storage permissions: " +
                    e.getMessage());
                return;
            }

            try {
                FileOutputStream fos = new FileOutputStream(pictureFile);
                fos.write(data);
                fos.close();
            } catch (FileNotFoundException e) {
                Log.d(TAG, "File not found: " + e.getMessage());
            } catch (IOException e) {
                Log.d(TAG, "Error accessing file: " + e.getMessage());
            }
        }
    };

Trigger capturing an image by calling the `Camera.takePicture()` method. The following example code shows how to call this method from a button `View.OnClickListener`.

    // Add a listener to the Capture button
    Button captureButton = (Button) findViewById(id.button_capture);
        captureButton.setOnClickListener(
            new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // get an image from the camera
                mCamera.takePicture(null, null, mPicture);
            }
        }
    );

Note: The `mPicture` member in the following example refers to the example code above.

Caution: Remember to release the `Camera` object by calling the `Camera.release()` when your application is done using it! For information about how to release the camera, see Releasing the camera.

### Capturing videos

Video capture using the Android framework requires careful management of the `Camera` object and coordination with the `MediaRecorder` class. When recording video with `Camera`, you must manage the `Camera.lock()` and `Camera.unlock()` calls to allow `MediaRecorder` access to the camera hardware, in addition to the `Camera.open()` and `Camera.release()` calls.

Note: Starting with Android 4.0 (API level 14), the `Camera.lock()` and `Camera.unlock()` calls are managed for you automatically.

Unlike taking pictures with a device camera, capturing video requires a very particular call order. You must follow a specific order of execution to successfully prepare for and capture video with your application, as detailed below.

1. Open Camera - Use the `Camera.open()` to get an instance of the camera object.
2. Connect Preview - Prepare a live camera image preview by connecting a `SurfaceView` to the camera using `Camera.setPreviewDisplay()`.
3. Start Preview - Call `Camera.startPreview()` to begin displaying the live camera images.
4. Start Recording Video - The following steps must be completed in order to successfully record video:
   1. Unlock the Camera - Unlock the camera for use by `MediaRecorder` by calling `Camera.unlock()`.
   2. Configure MediaRecorder - Call in the following `MediaRecorder` methods in this order. For more information, see the `MediaRecorder` reference documentation.
      1. `setCamera()` - Set the camera to be used for video capture, use your application's current instance of `Camera`.
      2. `setAudioSource()` - Set the audio source, use `MediaRecorder.AudioSource.CAMCORDER`.
      3. `setVideoSource()` - Set the video source, use `MediaRecorder.VideoSource.CAMERA`.
      4. Set the video output format and encoding. For Android 2.2 (API Level 8) and higher, use the `MediaRecorder.setProfile` method, and get a profile instance using `CamcorderProfile.get()`. For versions of Android prior to 2.2, you must set the video output format and encoding parameters:
         1. `setOutputFormat()` - Set the output format, specify the default setting or `MediaRecorder.OutputFormat.MPEG_4`.
         2. `setAudioEncoder()` - Set the sound encoding type, specify the default setting or `MediaRecorder.AudioEncoder.AMR_NB`.
         3. `setVideoEncoder()` - Set the video encoding type, specify the default setting or `MediaRecorder.VideoEncoder.MPEG_4_SP`.
      5. `setOutputFile()` - Set the output file, use `getOutputMediaFile(MEDIA_TYPE_VIDEO).toString()` from the example method in the Saving Media Files section.
      6. `setPreviewDisplay()` - Specify the `SurfaceView` preview layout element for your application. Use the same object you specified for Connect Preview.

      Caution: You must call these `MediaRecorder` configuration methods in this order, otherwise your application will encounter errors and the recording will fail.

   3. Prepare MediaRecorder - Prepare the `MediaRecorder` with provided configuration settings by calling `MediaRecorder.prepare()`.
   4. Start MediaRecorder - Start recording video by calling `MediaRecorder.start()`.
5. Stop Recording Video - Call the following methods in order, to successfully complete a video recording:
   1. Stop MediaRecorder - Stop recording video by calling `MediaRecorder.stop()`.
   2. Reset MediaRecorder - Optionally, remove the configuration settings from the recorder by calling `MediaRecorder.reset()`.
   3. Release MediaRecorder - Release the `MediaRecorder` by calling `MediaRecorder.release()`.
   4. Lock the Camera - Lock the camera so that future `MediaRecorder` sessions can use it by calling `Camera.lock()`. Starting with Android 4.0 (API level 14), this call is not required unless the `MediaRecorder.prepare()` call fails.
6. Stop the Preview - When your activity has finished using the camera, stop the preview using `Camera.stopPreview()`.
7. Release Camera - Release the camera so that other applications can use it by calling `Camera.release()`.

Note: It is possible to use `MediaRecorder` without creating a camera preview first and skip the first few steps of this process. However, since users typically prefer to see a preview before starting a recording, that process is not discussed here.

#### Configuring MediaRecorder

When using the `MediaRecorder` class to record video, you must perform configuration steps in a specific order and then call the `MediaRecorder.prepare()` method to check and implement the configuration. The following example code demonstrates how to properly configure and prepare the `MediaRecorder` class for video recording.

    private boolean prepareVideoRecorder(){

        mCamera = getCameraInstance();
        mMediaRecorder = new MediaRecorder();

        // Step 1: Unlock and set camera to MediaRecorder
        mCamera.unlock();
        mMediaRecorder.setCamera(mCamera);

        // Step 2: Set sources
        mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
        mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);

        // Step 3: Set a CamcorderProfile (requires API Level 8 or higher)
        mMediaRecorder.setProfile(CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH));

        // Step 4: Set output file
        mMediaRecorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO).toString());

        // Step 5: Set the preview output
        mMediaRecorder.setPreviewDisplay(mPreview.getHolder().getSurface());

        // Step 6: 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;
    }

Prior to Android 2.2 (API Level 8), you must set the output format and encoding formats parameters directly, instead of using `CamcorderProfile`. This approach is demonstrated in the following code:

        // Step 3: Set output format and encoding (for versions prior to API Level 8)
        mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
        mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
        mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT);

The following video recording parameters for `MediaRecorder` are given default settings, however, you may want to adjust these settings for your application:

- `setVideoEncodingBitRate()`
- `setVideoSize()`
- `setVideoFrameRate()`
- `setAudioEncodingBitRate()`
- `setAudioChannels()`
- `setAudioSamplingRate()`

#### Starting and Stopping MediaRecorder

When starting and stopping video recording using the `MediaRecorder` class, you must follow a specific order, as listed below.

1. Unlock the camera with `Camera.unlock()`
2. Configure `MediaRecorder` as shown in the code example above
3. Start recording using `MediaRecorder.start()`
4. Record the video
5. Stop recording using `MediaRecorder.stop()`
6. Release the media recorder with `MediaRecorder.release()`
7. Lock the camera using `Camera.lock()`

The following example code demonstrates how to wire up a button to properly start and stop video recording using the camera and the `MediaRecorder` class.

Note: When completing a video recording, do not release the camera or else your preview will be stopped.

    private boolean isRecording = false;

    // Add a listener to the Capture button
    Button captureButton = (Button) findViewById(id.button_capture);
    captureButton.setOnClickListener(
        new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (isRecording) {
                    // stop recording and release camera
                    mMediaRecorder.stop();  // stop the recording
                    releaseMediaRecorder(); // release the MediaRecorder object
                    mCamera.lock();         // take camera access back from MediaRecorder

                    // inform the user that recording has stopped
                    setCaptureButtonText("Capture");
                    isRecording = false;
                } else {
                    // initialize video camera
                    if (prepareVideoRecorder()) {
                        // Camera is available and unlocked, MediaRecorder is prepared,
                        // now you can start recording
                        mMediaRecorder.start();

                        // inform the user that recording has started
                        setCaptureButtonText("Stop");
                        isRecording = true;
                    } else {
                        // prepare didn't work, release the camera
                        releaseMediaRecorder();
                        // inform user
                    }
                }
            }
        }
    );

Note: In the above example, the `prepareVideoRecorder()` method refers to the example code shown in Configuring MediaRecorder. This method takes care of locking the camera, configuring and preparing the `MediaRecorder` instance.

### Releasing the camera

Cameras are a resource that is shared by applications on a device. Your application can make use of the camera after getting an instance of `Camera`, and you must be particularly careful to release the camera object when your application stops using it, and as soon as your application is paused (`Activity.onPause()`). If your application does not properly release the camera, all subsequent attempts to access the camera, including those by your own application, will fail and may cause your or other applications to be shut down.

To release an instance of the `Camera` object, use the `Camera.release()` method, as shown in the example code below.

    public class CameraActivity extends Activity {
        private Camera mCamera;
        private SurfaceView mPreview;
        private MediaRecorder mMediaRecorder;

        ...

        @Override
        protected void onPause() {
            super.onPause();
            releaseMediaRecorder();       // if you are using MediaRecorder, release it first
            releaseCamera();              // release the camera immediately on pause event
        }

        private void releaseMediaRecorder(){
            if (mMediaRecorder != null) {
                mMediaRecorder.reset();   // clear recorder configuration
                mMediaRecorder.release(); // release the recorder object
                mMediaRecorder = null;
                mCamera.lock();           // lock camera for later use
            }
        }

        private void releaseCamera(){
            if (mCamera != null){
                mCamera.release();        // release the camera for other applications
                mCamera = null;
            }
        }
    }

Caution: If your application does not properly release the camera, all subsequent attempts to access the camera, including those by your own application, will fail and may cause your or other applications to be shut down.

## Saving Media Files

Media files created by users such as pictures and videos should be saved to a device's external storage directory (SD Card) to conserve system space and to allow users to access these files without their device. There are many possible directory locations to save media files on a device, however there are only two standard locations you should consider as a developer:

- `Environment.getExternalStoragePublicDirectory`(`Environment.DIRECTORY_PICTURES`) - This method returns the standard, shared and recommended location for saving pictures and videos. This directory is shared (public), so other applications can easily discover, read, change and delete files saved in this location. If your application is uninstalled by the user, media files saved to this location will not be removed. To avoid interfering with users existing pictures and videos, you should create a sub-directory for your application's media files within this directory, as shown in the code sample below. This method is available in Android 2.2 (API Level 8), for equivalent calls in earlier API versions, see Saving Shared Files.
- `Context.getExternalFilesDir`(`Environment.DIRECTORY_PICTURES`) - This method returns a standard location for saving pictures and videos which are associated with your application. If your application is uninstalled, any files saved in this location are removed. Security is not enforced for files in this location and other applications may read, change and delete them.

The following example code demonstrates how to create a `File` or `Uri` location for a media file that can be used when invoking a device's camera with an `Intent` or as part of a Building a Camera App.

    public static final int MEDIA_TYPE_IMAGE = 1;
    public static final int MEDIA_TYPE_VIDEO = 2;

    /** Create a file Uri for saving an image or video */
    private static Uri getOutputMediaFileUri(int type){
          return Uri.fromFile(getOutputMediaFile(type));
    }

    /** Create a File for saving an image or video */
    private static Uri getOutputMediaFile(int type){
        // To be safe, you should check that the SDCard is mounted
        // using Environment.getExternalStorageState() before doing this.

        File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
                  Environment.DIRECTORY_PICTURES), "MyCameraApp");
        // This location works best if you want the created images to be shared
        // between applications and persist after your app has been uninstalled.

        // Create the storage directory if it does not exist
        if (! mediaStorageDir.exists()){
            if (! mediaStorageDir.mkdirs()){
                Log.d("MyCameraApp", "failed to create directory");
                return null;
            }
        }

        // Create a media file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        File mediaFile;
        if (type == MEDIA_TYPE_IMAGE){
            mediaFile = new File(mediaStorageDir.getPath() + File.separator +
            "IMG_"+ timeStamp + ".jpg");
        } else if(type == MEDIA_TYPE_VIDEO) {
            mediaFile = new File(mediaStorageDir.getPath() + File.separator +
            "VID_"+ timeStamp + ".mp4");
        } else {
            return null;
        }

        return mediaFile;
    }

Note: `Environment.getExternalStoragePublicDirectory()` is available in Android 2.2 (API Level 8) or higher. If you are targeting devices with earlier versions of Android, use `Environment.getExternalStorageDirectory()` instead. For more information, see Saving Shared Files.

For more information about saving files on an Android device, see Data Storage.

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