Camera
  public
  
  
  
  class
  Camera
  
    extends Object
  
  
  
  
  
  
| java.lang.Object | |
| ↳ | android.hardware.Camera | 
      This class was deprecated
      in API level 21.
    We recommend using the new android.hardware.camera2 API for new
             applications.
  
The Camera class is used to set image capture settings, start/stop preview, snap pictures, and retrieve frames for encoding for video. This class is a client for the Camera service, which manages the actual camera hardware.
To access the device camera, you must declare the
 Manifest.permission.CAMERA permission in your Android
 Manifest. Also be sure to include the
 <uses-feature>
 manifest element to declare camera features used by your application.
 For example, if you use the camera and auto-focus feature, your Manifest
 should include the following:
<uses-permission android:name="android.permission.CAMERA" /> <uses-feature android:name="android.hardware.camera" /> <uses-feature android:name="android.hardware.camera.autofocus" />
To take pictures with this class, use the following steps:
- Obtain an instance of Camera from open(int).
- Get existing (default) settings with getParameters().
- If necessary, modify the returned Camera.Parametersobject and callsetParameters(android.hardware.Camera.Parameters).
- Call setDisplayOrientation(int)to ensure correct orientation of preview.
- Important: Pass a fully initialized SurfaceHoldertosetPreviewDisplay(android.view.SurfaceHolder). Without a surface, the camera will be unable to start the preview.
- Important: Call startPreview()to start updating the preview surface. Preview must be started before you can take a picture.
- When you want, call takePicture(android.hardware.Camera.ShutterCallback, android.hardware.Camera.PictureCallback, android.hardware.Camera.PictureCallback, android.hardware.Camera.PictureCallback)to capture a photo. Wait for the callbacks to provide the actual image data.
- After taking a picture, preview display will have stopped.  To take more
 photos, call startPreview()again first.
- Call stopPreview()to stop updating the preview surface.
- Important: Call release()to release the camera for use by other applications. Applications should release the camera immediately inActivity.onPause()(and re-open()it inActivity.onResume()).
To quickly switch to video recording mode, use these steps:
- Obtain and initialize a Camera and start preview as described above.
- Call unlock()to allow the media process to access the camera.
- Pass the camera to MediaRecorder.setCamera(Camera). SeeMediaRecorderinformation about video recording.
- When finished recording, call reconnect()to re-acquire and re-lock the camera.
- If desired, restart preview and take more photos or videos.
- Call stopPreview()andrelease()as described above.
This class is not thread-safe, and is meant for use from one event thread.
 Most long-running operations (preview, focus, photo capture, etc) happen
 asynchronously and invoke callbacks as necessary.  Callbacks will be invoked
 on the event thread open(int) was called from.  This class's methods
 must never be called from multiple threads at once.
Caution: Different Android-powered devices may have different hardware specifications, such as megapixel ratings and auto-focus capabilities. In order for your application to be compatible with more devices, you should not make assumptions about the device camera specifications.
Developer Guides
For more information about using cameras, read the Camera developer guide.
Summary
| Nested classes | |
|---|---|
| 
        
        
        
        
        class | Camera.Area
      This class was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.AutoFocusCallback
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.AutoFocusMoveCallback
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        class | Camera.CameraInfo
      This class was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.ErrorCallback
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        class | Camera.Face
      This class was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.FaceDetectionListener
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.OnZoomChangeListener
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        class | Camera.Parameters
      This class was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.PictureCallback
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.PreviewCallback
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        interface | Camera.ShutterCallback
      This interface was deprecated
      in API level 21.
    We recommend using the new  | 
| 
        
        
        
        
        class | Camera.Size
      This class was deprecated
      in API level 21.
    We recommend using the new  | 
| Constants | |
|---|---|
| String | ACTION_NEW_PICTUREBroadcast Action: A new picture is taken by the camera, and the entry of the picture has been added to the media store. | 
| String | ACTION_NEW_VIDEOBroadcast Action: A new video is recorded by the camera, and the entry of the video has been added to the media store. | 
| int | CAMERA_ERROR_EVICTEDCamera was disconnected due to use by higher priority user. | 
| int | CAMERA_ERROR_SERVER_DIEDMedia server died. | 
| int | CAMERA_ERROR_UNKNOWNUnspecified camera error. | 
| Public methods | |
|---|---|
| 
        
        
        
        final
        
        void | 
      addCallbackBuffer(byte[] callbackBuffer)
      Adds a pre-allocated buffer to the preview callback buffer queue. | 
| 
        
        
        
        final
        
        void | 
      autoFocus(Camera.AutoFocusCallback cb)
      Starts camera auto-focus and registers a callback function to run when the camera is focused. | 
| 
        
        
        
        final
        
        void | 
      cancelAutoFocus()
      Cancels any auto-focus function in progress. | 
| 
        
        
        
        final
        
        boolean | 
      enableShutterSound(boolean enabled)
      Enable or disable the default shutter sound when taking a picture. | 
| 
        
        
        static
        
        
        void | 
      getCameraInfo(int cameraId, Camera.CameraInfo cameraInfo)
      Returns the information about a particular camera. | 
| 
        
        
        static
        
        
        int | 
      getNumberOfCameras()
      Returns the number of physical cameras available on this device. | 
| 
        
        
        
        
        
        Camera.Parameters | 
      getParameters()
      Returns the current settings for this Camera service. | 
| 
        
        
        
        final
        
        void | 
      lock()
      Re-locks the camera to prevent other processes from accessing it. | 
| 
        
        
        static
        
        
        Camera | 
      open()
      Creates a new Camera object to access the first back-facing camera on the device. | 
| 
        
        
        static
        
        
        Camera | 
      open(int cameraId)
      Creates a new Camera object to access a particular hardware camera. | 
| 
        
        
        
        final
        
        void | 
      reconnect()
      Reconnects to the camera service after another process used it. | 
| 
        
        
        
        final
        
        void | 
      release()
      Disconnects and releases the Camera object resources. | 
| 
        
        
        
        
        
        void | 
      setAutoFocusMoveCallback(Camera.AutoFocusMoveCallback cb)
      Sets camera auto-focus move callback. | 
| 
        
        
        
        final
        
        void | 
      setDisplayOrientation(int degrees)
      Set the clockwise rotation of preview display in degrees. | 
| 
        
        
        
        final
        
        void | 
      setErrorCallback(Camera.ErrorCallback cb)
      Registers a callback to be invoked when an error occurs. | 
| 
        
        
        
        final
        
        void | 
      setFaceDetectionListener(Camera.FaceDetectionListener listener)
      Registers a listener to be notified about the faces detected in the preview frame. | 
| 
        
        
        
        final
        
        void | 
      setOneShotPreviewCallback(Camera.PreviewCallback cb)
      Installs a callback to be invoked for the next preview frame in addition to displaying it on the screen. | 
| 
        
        
        
        
        
        void | 
      setParameters(Camera.Parameters params)
      Changes the settings for this Camera service. | 
| 
        
        
        
        final
        
        void | 
      setPreviewCallback(Camera.PreviewCallback cb)
      Installs a callback to be invoked for every preview frame in addition to displaying them on the screen. | 
| 
        
        
        
        final
        
        void | 
      setPreviewCallbackWithBuffer(Camera.PreviewCallback cb)
      Installs a callback to be invoked for every preview frame, using
 buffers supplied with  | 
| 
        
        
        
        final
        
        void | 
      setPreviewDisplay(SurfaceHolder holder)
      Sets the  | 
| 
        
        
        
        final
        
        void | 
      setPreviewTexture(SurfaceTexture surfaceTexture)
      Sets the  | 
| 
        
        
        
        final
        
        void | 
      setZoomChangeListener(Camera.OnZoomChangeListener listener)
      Registers a listener to be notified when the zoom value is updated by the camera driver during smooth zoom. | 
| 
        
        
        
        final
        
        void | 
      startFaceDetection()
      Starts the face detection. | 
| 
        
        
        
        final
        
        void | 
      startPreview()
      Starts capturing and drawing preview frames to the screen. | 
| 
        
        
        
        final
        
        void | 
      startSmoothZoom(int value)
      Zooms to the requested value smoothly. | 
| 
        
        
        
        final
        
        void | 
      stopFaceDetection()
      Stops the face detection. | 
| 
        
        
        
        final
        
        void | 
      stopPreview()
      Stops capturing and drawing preview frames to the surface, and
 resets the camera for a future call to  | 
| 
        
        
        
        final
        
        void | 
      stopSmoothZoom()
      Stops the smooth zoom. | 
| 
        
        
        
        final
        
        void | 
      takePicture(Camera.ShutterCallback shutter, Camera.PictureCallback raw, Camera.PictureCallback postview, Camera.PictureCallback jpeg)
      Triggers an asynchronous image capture. | 
| 
        
        
        
        final
        
        void | 
      takePicture(Camera.ShutterCallback shutter, Camera.PictureCallback raw, Camera.PictureCallback jpeg)
      Equivalent to takePicture(Shutter, raw, null, jpeg) | 
| 
        
        
        
        final
        
        void | 
      unlock()
      Unlocks the camera to allow another process to access it. | 
| Protected methods | |
|---|---|
| 
        
        
        
        
        
        void | 
      finalize()
      Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. | 
| Inherited methods | |
|---|---|
Constants
ACTION_NEW_PICTURE
public static final String ACTION_NEW_PICTURE
Broadcast Action:  A new picture is taken by the camera, and the entry of
 the picture has been added to the media store.
 Intent.getData() is URI of the picture.
 
In Android N this broadcast was removed, and
 applications are recommended to use
 JobInfo.Builder.JobInfo.Builder.addTriggerContentUri(TriggerContentUri)
 instead.
In Android O this broadcast has been brought
 back, but only for registered receivers.  Apps that are actively running can
 again listen to the broadcast if they want an immediate clear signal about a picture
 being taken, however anything doing heavy work (or needing to be launched) as a result of
 this should still use JobScheduler.
Constant Value: "android.hardware.action.NEW_PICTURE"
ACTION_NEW_VIDEO
public static final String ACTION_NEW_VIDEO
Broadcast Action:  A new video is recorded by the camera, and the entry
 of the video has been added to the media store.
 Intent.getData() is URI of the video.
 
In Android N this broadcast was removed, and
 applications are recommended to use
 JobInfo.Builder.JobInfo.Builder.addTriggerContentUri(TriggerContentUri)
 instead.
In Android O this broadcast has been brought
 back, but only for registered receivers.  Apps that are actively running can
 again listen to the broadcast if they want an immediate clear signal about a video
 being taken, however anything doing heavy work (or needing to be launched) as a result of
 this should still use JobScheduler.
Constant Value: "android.hardware.action.NEW_VIDEO"
CAMERA_ERROR_EVICTED
public static final int CAMERA_ERROR_EVICTED
Camera was disconnected due to use by higher priority user.
See also:
Constant Value: 2 (0x00000002)
CAMERA_ERROR_SERVER_DIED
public static final int CAMERA_ERROR_SERVER_DIED
Media server died. In this case, the application must release the Camera object and instantiate a new one.
See also:
Constant Value: 100 (0x00000064)
CAMERA_ERROR_UNKNOWN
public static final int CAMERA_ERROR_UNKNOWN
Unspecified camera error.
See also:
Constant Value: 1 (0x00000001)
Public methods
addCallbackBuffer
public final void addCallbackBuffer (byte[] callbackBuffer)
Adds a pre-allocated buffer to the preview callback buffer queue. Applications can add one or more buffers to the queue. When a preview frame arrives and there is still at least one available buffer, the buffer will be used and removed from the queue. Then preview callback is invoked with the buffer. If a frame arrives and there is no buffer left, the frame is discarded. Applications should add buffers back when they finish processing the data in them.
For formats besides YV12, the size of the buffer is determined by
 multiplying the preview image width, height, and bytes per pixel. The
 width and height can be read from
 Camera.Parameters.getPreviewSize(). Bytes per pixel can be
 computed from ImageFormat.getBitsPerPixel(int) /
 8, using the image format from
 Camera.Parameters.getPreviewFormat().
 
If using the ImageFormat.YV12 format, the
 size can be calculated using the equations listed in
 Camera.Parameters.setPreviewFormat.
 
This method is only necessary when
 setPreviewCallbackWithBuffer(android.hardware.Camera.PreviewCallback) is used. When
 setPreviewCallback(android.hardware.Camera.PreviewCallback) or
 setOneShotPreviewCallback(android.hardware.Camera.PreviewCallback) are used, buffers
 are automatically allocated. When a supplied buffer is too small to
 hold the preview frame data, preview callback will return null and
 the buffer will be removed from the buffer queue.
| Parameters | |
|---|---|
| callbackBuffer | byte: the buffer to add to the queue. The size of the
   buffer must match the values described above. | 
autoFocus
public final void autoFocus (Camera.AutoFocusCallback cb)
Starts camera auto-focus and registers a callback function to run when
 the camera is focused.  This method is only valid when preview is active
 (between startPreview() and before stopPreview()).
 
Callers should check
 Camera.Parameters.getFocusMode() to determine if
 this method should be called. If the camera does not support auto-focus,
 it is a no-op and AutoFocusCallback.onAutoFocus(boolean, Camera)
 callback will be called immediately.
 
If your application should not be installed on devices without auto-focus, you must declare that your application uses auto-focus with the <uses-feature> manifest element.
If the current flash mode is not
 Camera.Parameters.FLASH_MODE_OFF, flash may be
 fired during auto-focus, depending on the driver and camera hardware.
Auto-exposure lock Camera.Parameters.getAutoExposureLock()
 and auto-white balance locks Camera.Parameters.getAutoWhiteBalanceLock()
 do not change during and after autofocus. But auto-focus routine may stop
 auto-exposure and auto-white balance transiently during focusing.
 
Stopping preview with stopPreview(), or triggering still
 image capture with takePicture(android.hardware.Camera.ShutterCallback, android.hardware.Camera.PictureCallback, android.hardware.Camera.PictureCallback), will not change the
 the focus position. Applications must call cancelAutoFocus to reset the
 focus.
If autofocus is successful, consider using
 MediaActionSound to properly play back an autofocus
 success sound to the user.
| Parameters | |
|---|---|
| cb | Camera.AutoFocusCallback: the callback to run | 
| Throws | |
|---|---|
| RuntimeException | if starting autofocus fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
cancelAutoFocus
public final void cancelAutoFocus ()
Cancels any auto-focus function in progress. Whether or not auto-focus is currently in progress, this function will return the focus position to the default. If the camera does not support auto-focus, this is a no-op.
| Throws | |
|---|---|
| RuntimeException | if canceling autofocus fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
See also:
enableShutterSound
public final boolean enableShutterSound (boolean enabled)
Enable or disable the default shutter sound when taking a picture.
By default, the camera plays the system-defined camera shutter sound
 when takePicture(ShutterCallback, PictureCallback, PictureCallback) is called. Using this method, the shutter sound
 can be disabled. It is strongly recommended that an alternative shutter
 sound is played in the ShutterCallback when the system shutter
 sound is disabled.
Note that devices may not always allow disabling the camera shutter
 sound. If the shutter sound state cannot be set to the desired value,
 this method will return false. CameraInfo.canDisableShutterSound
 can be used to determine whether the device will allow the shutter sound
 to be disabled.
| Parameters | |
|---|---|
| enabled | boolean: whether the camera should play the system shutter sound
                whentakePictureis called. | 
| Returns | |
|---|---|
| boolean | trueif the shutter sound state was successfully
         changed.falseif the shutter sound state could not be
         changed.trueis also returned if shutter sound playback
         is already set to the requested state. | 
| Throws | |
|---|---|
| RuntimeException | if the call fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
getCameraInfo
public static void getCameraInfo (int cameraId, 
                Camera.CameraInfo cameraInfo)Returns the information about a particular camera.
 If getNumberOfCameras() returns N, the valid id is 0 to N-1.
| Parameters | |
|---|---|
| cameraId | int | 
| cameraInfo | Camera.CameraInfo | 
| Throws | |
|---|---|
| RuntimeException | if an invalid ID is provided, or if there is an error retrieving the information (generally due to a hardware or other low-level failure). | 
getNumberOfCameras
public static int getNumberOfCameras ()
Returns the number of physical cameras available on this device.
 The return value of this method might change dynamically if the device
 supports external cameras and an external camera is connected or
 disconnected.
 If there is a
 logical multi-camera in the system, to maintain app backward compatibility, this method will
 only expose one camera per facing for all logical camera and physical camera groups.
 Use camera2 API to see all cameras.
| Returns | |
|---|---|
| int | total number of accessible camera devices, or 0 if there are no cameras or an error was encountered enumerating them. | 
getParameters
public Camera.Parameters getParameters ()
Returns the current settings for this Camera service.
 If modifications are made to the returned Parameters, they must be passed
 to setParameters(android.hardware.Camera.Parameters) to take effect.
| Returns | |
|---|---|
| Camera.Parameters | |
| Throws | |
|---|---|
| RuntimeException | if reading parameters fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
See also:
lock
public final void lock ()
Re-locks the camera to prevent other processes from accessing it.
 Camera objects are locked by default unless unlock() is
 called.  Normally reconnect() is used instead.
 
Since API level 14, camera is automatically locked for applications in
 MediaRecorder.start(). Applications can use the
 camera (ex: zoom) after recording starts. There is no need to call this
 after recording starts or stops.
 
If you are not recording video, you probably do not need this method.
| Throws | |
|---|---|
| RuntimeException | if the camera cannot be re-locked (for example, if the camera is still in use by another process). | 
open
public static Camera open ()
Creates a new Camera object to access the first back-facing camera on the
 device. If the device does not have a back-facing camera, this returns
 null. Otherwise acts like the open(int) call.
| Returns | |
|---|---|
| Camera | a new Camera object for the first back-facing camera, or null if there is no backfacing camera | 
See also:
open
public static Camera open (int cameraId)
Creates a new Camera object to access a particular hardware camera. If the same camera is opened by other applications, this will throw a RuntimeException.
You must call release() when you are done using the camera,
 otherwise it will remain locked and be unavailable to other applications.
 
Your application should only have one Camera object active at a time for a particular hardware camera.
Callbacks from other methods are delivered to the event loop of the thread which called open(). If this thread has no event loop, then callbacks are delivered to the main application event loop. If there is no main application event loop, callbacks are not delivered.
Caution: On some devices, this method may
 take a long time to complete.  It is best to call this method from a
 worker thread (possibly using AsyncTask) to avoid
 blocking the main application UI thread.
| Parameters | |
|---|---|
| cameraId | int: the hardware camera to access, between 0 andgetNumberOfCameras()-1. | 
| Returns | |
|---|---|
| Camera | a new Camera object, connected, locked and ready for use. | 
| Throws | |
|---|---|
| RuntimeException | if opening the camera fails (for example, if the camera is in use by another process or device policy manager has disabled the camera). | 
reconnect
public final void reconnect ()
Reconnects to the camera service after another process used it.
 After unlock() is called, another process may use the
 camera; when the process is done, you must reconnect to the camera,
 which will re-acquire the lock and allow you to continue using the
 camera.
 
Since API level 14, camera is automatically locked for applications in
 MediaRecorder.start(). Applications can use the
 camera (ex: zoom) after recording starts. There is no need to call this
 after recording starts or stops.
 
If you are not recording video, you probably do not need this method.
| Throws | |
|---|---|
| IOException | if a connection cannot be re-established (for example, if the camera is still in use by another process). | 
| RuntimeException | if release() has been called on this Camera instance. | 
release
public final void release ()
Disconnects and releases the Camera object resources.
You must call this as soon as you're done with the Camera object.
setAutoFocusMoveCallback
public void setAutoFocusMoveCallback (Camera.AutoFocusMoveCallback cb)
Sets camera auto-focus move callback.
| Parameters | |
|---|---|
| cb | Camera.AutoFocusMoveCallback: the callback to run | 
| Throws | |
|---|---|
| RuntimeException | if enabling the focus move callback fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
setDisplayOrientation
public final void setDisplayOrientation (int degrees)
Set the clockwise rotation of preview display in degrees. This affects the preview frames and the picture displayed after snapshot. This method is useful for portrait mode applications. Note that preview display of front-facing cameras is flipped horizontally before the rotation, that is, the image is reflected along the central vertical axis of the camera sensor. So the users can see themselves as looking into a mirror.
This does not affect the order of byte array passed in Camera.PreviewCallback.onPreviewFrame(byte, Camera), JPEG pictures, or recorded videos. This
 method is not allowed to be called during preview.
 
If you want to make the camera image show in the same orientation as the display, you can use the following code.
 public static void setCameraDisplayOrientation(Activity activity,
         int cameraId, android.hardware.Camera camera) {
     android.hardware.Camera.CameraInfo info =
             new android.hardware.Camera.CameraInfo();
     android.hardware.Camera.getCameraInfo(cameraId, info);
     int rotation = activity.getWindowManager().getDefaultDisplay()
             .getRotation();
     int degrees = 0;
     switch (rotation) {
         case Surface.ROTATION_0: degrees = 0; break;
         case Surface.ROTATION_90: degrees = 90; break;
         case Surface.ROTATION_180: degrees = 180; break;
         case Surface.ROTATION_270: degrees = 270; break;
     }
     int result;
     if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
         result = (info.orientation + degrees) % 360;
         result = (360 - result) % 360;  // compensate the mirror
     } else {  // back-facing
         result = (info.orientation - degrees + 360) % 360;
     }
     camera.setDisplayOrientation(result);
 }
 Starting from API level 14, this method can be called when preview is active.
Note: Before API level 24, the default value for orientation is 0. Starting in API level 24, the default orientation will be such that applications in forced-landscape mode will have correct preview orientation, which may be either a default of 0 or 180. Applications that operate in portrait mode or allow for changing orientation must still call this method after each orientation change to ensure correct preview display in all cases.
| Parameters | |
|---|---|
| degrees | int: the angle that the picture will be rotated clockwise.
                Valid values are 0, 90, 180, and 270. | 
| Throws | |
|---|---|
| RuntimeException | if setting orientation fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
See also:
setErrorCallback
public final void setErrorCallback (Camera.ErrorCallback cb)
Registers a callback to be invoked when an error occurs.
| Parameters | |
|---|---|
| cb | Camera.ErrorCallback: The callback to run | 
setFaceDetectionListener
public final void setFaceDetectionListener (Camera.FaceDetectionListener listener)
Registers a listener to be notified about the faces detected in the preview frame.
| Parameters | |
|---|---|
| listener | Camera.FaceDetectionListener: the listener to notify | 
See also:
setOneShotPreviewCallback
public final void setOneShotPreviewCallback (Camera.PreviewCallback cb)
Installs a callback to be invoked for the next preview frame in addition to displaying it on the screen. After one invocation, the callback is cleared. This method can be called any time, even when preview is live. Any other preview callbacks are overridden.
If you are using the preview data to create video or still images,
 strongly consider using MediaActionSound to
 properly indicate image capture or recording start/stop to the user.
| Parameters | |
|---|---|
| cb | Camera.PreviewCallback: a callback object that receives a copy of the next preview frame,
     or null to stop receiving callbacks. | 
| Throws | |
|---|---|
| RuntimeException | if release() has been called on this Camera instance. | 
See also:
setParameters
public void setParameters (Camera.Parameters params)
Changes the settings for this Camera service.
| Parameters | |
|---|---|
| params | Camera.Parameters: the Parameters to use for this Camera service | 
| Throws | |
|---|---|
| RuntimeException | if any parameter is invalid or not supported. | 
See also:
setPreviewCallback
public final void setPreviewCallback (Camera.PreviewCallback cb)
Installs a callback to be invoked for every preview frame in addition to displaying them on the screen. The callback will be repeatedly called for as long as preview is active. This method can be called at any time, even while preview is live. Any other preview callbacks are overridden.
If you are using the preview data to create video or still images,
 strongly consider using MediaActionSound to
 properly indicate image capture or recording start/stop to the user.
| Parameters | |
|---|---|
| cb | Camera.PreviewCallback: a callback object that receives a copy of each preview frame,
     or null to stop receiving callbacks. | 
| Throws | |
|---|---|
| RuntimeException | if release() has been called on this Camera instance. | 
See also:
setPreviewCallbackWithBuffer
public final void setPreviewCallbackWithBuffer (Camera.PreviewCallback cb)
Installs a callback to be invoked for every preview frame, using
 buffers supplied with addCallbackBuffer(byte[]), in addition to
 displaying them on the screen.  The callback will be repeatedly called
 for as long as preview is active and buffers are available.  Any other
 preview callbacks are overridden.
The purpose of this method is to improve preview efficiency and frame
 rate by allowing preview frame memory reuse.  You must call
 addCallbackBuffer(byte[]) at some point -- before or after
 calling this method -- or no callbacks will received.
The buffer queue will be cleared if this method is called with a null
 callback, setPreviewCallback(android.hardware.Camera.PreviewCallback) is called,
 or setOneShotPreviewCallback(android.hardware.Camera.PreviewCallback) is
 called.
If you are using the preview data to create video or still images,
 strongly consider using MediaActionSound to
 properly indicate image capture or recording start/stop to the user.
| Parameters | |
|---|---|
| cb | Camera.PreviewCallback: a callback object that receives a copy of the preview frame,
     or null to stop receiving callbacks and clear the buffer queue. | 
| Throws | |
|---|---|
| RuntimeException | if release() has been called on this Camera instance. | 
setPreviewDisplay
public final void setPreviewDisplay (SurfaceHolder holder)
Sets the Surface to be used for live preview.
 Either a surface or surface texture is necessary for preview, and
 preview is necessary to take pictures.  The same surface can be re-set
 without harm.  Setting a preview surface will un-set any preview surface
 texture that was set via setPreviewTexture(SurfaceTexture).
 
The SurfaceHolder must already contain a surface when this
 method is called.  If you are using SurfaceView,
 you will need to register a SurfaceHolder.Callback with
 SurfaceHolder.addCallback(SurfaceHolder.Callback) and wait for
 SurfaceHolder.Callback.surfaceCreated(SurfaceHolder) before
 calling setPreviewDisplay() or starting preview.
 
This method must be called before startPreview().  The
 one exception is that if the preview surface is not set (or set to null)
 before startPreview() is called, then this method may be called once
 with a non-null parameter to set the preview surface.  (This allows
 camera setup and surface creation to happen in parallel, saving time.)
 The preview surface may not otherwise change while preview is running.
| Parameters | |
|---|---|
| holder | SurfaceHolder: containing the Surface on which to place the preview,
     or null to remove the preview surface | 
| Throws | |
|---|---|
| IOException | if the method fails (for example, if the surface is unavailable or unsuitable). | 
| RuntimeException | if release() has been called on this Camera instance. | 
setPreviewTexture
public final void setPreviewTexture (SurfaceTexture surfaceTexture)
Sets the SurfaceTexture to be used for live preview.
 Either a surface or surface texture is necessary for preview, and
 preview is necessary to take pictures.  The same surface texture can be
 re-set without harm.  Setting a preview surface texture will un-set any
 preview surface that was set via setPreviewDisplay(SurfaceHolder).
 
This method must be called before startPreview().  The
 one exception is that if the preview surface texture is not set (or set
 to null) before startPreview() is called, then this method may be called
 once with a non-null parameter to set the preview surface.  (This allows
 camera setup and surface creation to happen in parallel, saving time.)
 The preview surface texture may not otherwise change while preview is
 running.
 
The timestamps provided by SurfaceTexture.getTimestamp() for a
 SurfaceTexture set as the preview texture have an unspecified zero point,
 and cannot be directly compared between different cameras or different
 instances of the same camera, or across multiple runs of the same
 program.
 
If you are using the preview data to create video or still images,
 strongly consider using MediaActionSound to
 properly indicate image capture or recording start/stop to the user.
| Parameters | |
|---|---|
| surfaceTexture | SurfaceTexture: theSurfaceTextureto which the preview
     images are to be sent or null to remove the current preview surface
     texture | 
| Throws | |
|---|---|
| IOException | if the method fails (for example, if the surface texture is unavailable or unsuitable). | 
| RuntimeException | if release() has been called on this Camera instance. | 
setZoomChangeListener
public final void setZoomChangeListener (Camera.OnZoomChangeListener listener)
Registers a listener to be notified when the zoom value is updated by the camera driver during smooth zoom.
| Parameters | |
|---|---|
| listener | Camera.OnZoomChangeListener: the listener to notify | 
See also:
startFaceDetection
public final void startFaceDetection ()
Starts the face detection. This should be called after preview is started.
 The camera will notify FaceDetectionListener of the detected
 faces in the preview frame. The detected faces may be the same as the
 previous ones. Applications should call stopFaceDetection() to
 stop the face detection. This method is supported if Camera.Parameters.getMaxNumDetectedFaces() returns a number larger than 0.
 If the face detection has started, apps should not call this again.
 
When the face detection is running, Parameters.setWhiteBalance(String),
 Parameters.setFocusAreas(List), and Parameters.setMeteringAreas(List)
 have no effect. The camera uses the detected faces to do auto-white balance,
 auto exposure, and autofocus.
 
If the apps call autoFocus(android.hardware.Camera.AutoFocusCallback), the camera
 will stop sending face callbacks. The last face callback indicates the
 areas used to do autofocus. After focus completes, face detection will
 resume sending face callbacks. If the apps call cancelAutoFocus(), the face callbacks will also resume.
After calling takePicture(android.hardware.Camera.ShutterCallback, android.hardware.Camera.PictureCallback, android.hardware.Camera.PictureCallback) or stopPreview(), and then resuming
 preview with startPreview(), the apps should call this method
 again to resume face detection.
| Throws | |
|---|---|
| IllegalArgumentException | if the face detection is unsupported. | 
| RuntimeException | if the method fails or the face detection is already running. | 
startPreview
public final void startPreview ()
Starts capturing and drawing preview frames to the screen.
 Preview will not actually start until a surface is supplied
 with setPreviewDisplay(android.view.SurfaceHolder) or
 setPreviewTexture(android.graphics.SurfaceTexture).
 
If setPreviewCallback(android.hardware.Camera.PreviewCallback),
 setOneShotPreviewCallback(android.hardware.Camera.PreviewCallback), or
 setPreviewCallbackWithBuffer(android.hardware.Camera.PreviewCallback) were
 called, Camera.PreviewCallback.onPreviewFrame(byte[], Camera)
 will be called when preview data becomes available.
| Throws | |
|---|---|
| RuntimeException | if starting preview fails; usually this would be
    because of a hardware or other low-level error, or because release()
    has been called on this Camera instance. The QCIF (176x144) exception
    mentioned in setPreviewSizeandsetPictureSizecan also cause this
    exception be thrown. | 
startSmoothZoom
public final void startSmoothZoom (int value)
Zooms to the requested value smoothly. The driver will notify OnZoomChangeListener of the zoom value and whether zoom is stopped at
 the time. For example, suppose the current zoom is 0 and startSmoothZoom
 is called with value 3. The
 Camera.OnZoomChangeListener.onZoomChange(int, boolean, Camera)
 method will be called three times with zoom values 1, 2, and 3.
 Applications can call stopSmoothZoom() to stop the zoom earlier.
 Applications should not call startSmoothZoom again or change the zoom
 value before zoom stops. If the supplied zoom value equals to the current
 zoom value, no zoom callback will be generated. This method is supported
 if Camera.Parameters.isSmoothZoomSupported()
 returns true.
| Parameters | |
|---|---|
| value | int: zoom value. The valid range is 0 toCamera.Parameters.getMaxZoom(). | 
| Throws | |
|---|---|
| IllegalArgumentException | if the zoom value is invalid. | 
| RuntimeException | if the method fails. | 
stopFaceDetection
public final void stopFaceDetection ()
Stops the face detection.
See also:
stopPreview
public final void stopPreview ()
Stops capturing and drawing preview frames to the surface, and
 resets the camera for a future call to startPreview().
| Throws | |
|---|---|
| RuntimeException | if stopping preview fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
stopSmoothZoom
public final void stopSmoothZoom ()
Stops the smooth zoom. Applications should wait for the OnZoomChangeListener to know when the zoom is actually stopped. This
 method is supported if Camera.Parameters.isSmoothZoomSupported() is true.
| Throws | |
|---|---|
| RuntimeException | if the method fails. | 
takePicture
public final void takePicture (Camera.ShutterCallback shutter, Camera.PictureCallback raw, Camera.PictureCallback postview, Camera.PictureCallback jpeg)
Triggers an asynchronous image capture. The camera service will initiate a series of callbacks to the application as the image capture progresses. The shutter callback occurs after the image is captured. This can be used to trigger a sound to let the user know that image has been captured. The raw callback occurs when the raw image data is available (NOTE: the data will be null if there is no raw image callback buffer available or the raw image callback buffer is not large enough to hold the raw image). The postview callback occurs when a scaled, fully processed postview image is available (NOTE: not all hardware supports this). The jpeg callback occurs when the compressed image is available. If the application does not need a particular callback, a null can be passed instead of a callback method.
This method is only valid when preview is active (after
 startPreview()).  Preview will be stopped after the image is
 taken; callers must call startPreview() again if they want to
 re-start preview or take more pictures. This should not be called between
 MediaRecorder.start() and
 MediaRecorder.stop().
 
After calling this method, you must not call startPreview()
 or take another picture until the JPEG callback has returned.
| Parameters | |
|---|---|
| shutter | Camera.ShutterCallback: the callback for image capture moment, or null | 
| raw | Camera.PictureCallback: the callback for raw (uncompressed) image data, or null | 
| postview | Camera.PictureCallback: callback with postview image data, may be null | 
| jpeg | Camera.PictureCallback: the callback for JPEG image data, or null | 
| Throws | |
|---|---|
| RuntimeException | if starting picture capture fails; usually this would be because of a hardware or other low-level error, or because release() has been called on this Camera instance. | 
takePicture
public final void takePicture (Camera.ShutterCallback shutter, Camera.PictureCallback raw, Camera.PictureCallback jpeg)
Equivalent to
takePicture(Shutter, raw, null, jpeg)
| Parameters | |
|---|---|
| shutter | Camera.ShutterCallback | 
| raw | Camera.PictureCallback | 
| jpeg | Camera.PictureCallback | 
unlock
public final void unlock ()
Unlocks the camera to allow another process to access it.
 Normally, the camera is locked to the process with an active Camera
 object until release() is called.  To allow rapid handoff
 between processes, you can call this method to release the camera
 temporarily for another process to use; once the other process is done
 you can call reconnect() to reclaim the camera.
 
This must be done before calling
 MediaRecorder.setCamera(Camera). This cannot be
 called after recording starts.
 
If you are not recording video, you probably do not need this method.
| Throws | |
|---|---|
| RuntimeException | if the camera cannot be unlocked. | 
Protected methods
finalize
protected void finalize ()
Called by the garbage collector on an object when garbage collection
 determines that there are no more references to the object.
 A subclass overrides the finalize method to dispose of
 system resources or to perform other cleanup.
 
 The general contract of finalize is that it is invoked
 if and when the Java virtual
 machine has determined that there is no longer any
 means by which this object can be accessed by any thread that has
 not yet died, except as a result of an action taken by the
 finalization of some other object or class which is ready to be
 finalized. The finalize method may take any action, including
 making this object available again to other threads; the usual purpose
 of finalize, however, is to perform cleanup actions before
 the object is irrevocably discarded. For example, the finalize method
 for an object that represents an input/output connection might perform
 explicit I/O transactions to break the connection before the object is
 permanently discarded.
 
 The finalize method of class Object performs no
 special action; it simply returns normally. Subclasses of
 Object may override this definition.
 
 The Java programming language does not guarantee which thread will
 invoke the finalize method for any given object. It is
 guaranteed, however, that the thread that invokes finalize will not
 be holding any user-visible synchronization locks when finalize is
 invoked. If an uncaught exception is thrown by the finalize method,
 the exception is ignored and finalization of that object terminates.
 
 After the finalize method has been invoked for an object, no
 further action is taken until the Java virtual machine has again
 determined that there is no longer any means by which this object can
 be accessed by any thread that has not yet died, including possible
 actions by other objects or classes which are ready to be finalized,
 at which point the object may be discarded.
 
 The finalize method is never invoked more than once by a Java
 virtual machine for any given object.
 
 Any exception thrown by the finalize method causes
 the finalization of this object to be halted, but is otherwise
 ignored.
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Last updated 2025-02-10 UTC.
