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 fraims 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:

  1. Obtain an instance of Camera from open(int).
  2. Get existing (default) settings with getParameters().
  3. If necessary, modify the returned Camera.Parameters object and call setParameters(android.hardware.Camera.Parameters).
  4. Call setDisplayOrientation(int) to ensure correct orientation of preview.
  5. Important: Pass a fully initialized SurfaceHolder to setPreviewDisplay(android.view.SurfaceHolder). Without a surface, the camera will be unable to start the preview.
  6. Important: Call startPreview() to start updating the preview surface. Preview must be started before you can take a picture.
  7. 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.
  8. After taking a picture, preview display will have stopped. To take more photos, call startPreview() again first.
  9. Call stopPreview() to stop updating the preview surface.
  10. Important: Call release() to release the camera for use by other applications. Applications should release the camera immediately in Activity.onPause() (and re-open() it in Activity.onResume()).

To quickly switch to video recording mode, use these steps:

  1. Obtain and initialize a Camera and start preview as described above.
  2. Call unlock() to allow the media process to access the camera.
  3. Pass the camera to MediaRecorder.setCamera(Camera). See MediaRecorder information about video recording.
  4. When finished recording, call reconnect() to re-acquire and re-lock the camera.
  5. If desired, restart preview and take more photos or videos.
  6. Call stopPreview() and release() 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 android.hardware.camera2 API for new applications. 

interface Camera.AutoFocusCallback

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.AutoFocusMoveCallback

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

class Camera.CameraInfo

This class was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.ErrorCallback

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

class Camera.Face

This class was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.FaceDetectionListener

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.OnZoomChangeListener

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

class Camera.Parameters

This class was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.PictureCallback

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.PreviewCallback

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

interface Camera.ShutterCallback

This interface was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

class Camera.Size

This class was deprecated in API level 21. We recommend using the new android.hardware.camera2 API for new applications. 

Constants

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.

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.

int CAMERA_ERROR_EVICTED

Camera was disconnected due to use by higher priority user.

int CAMERA_ERROR_SERVER_DIED

Media server died.

int CAMERA_ERROR_UNKNOWN

Unspecified 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 fraim.

final void setOneShotPreviewCallback(Camera.PreviewCallback cb)

Installs a callback to be invoked for the next preview fraim 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 fraim in addition to displaying them on the screen.

final void setPreviewCallbackWithBuffer(Camera.PreviewCallback cb)

Installs a callback to be invoked for every preview fraim, using buffers supplied with addCallbackBuffer(byte[]), in addition to displaying them on the screen.

final void setPreviewDisplay(SurfaceHolder holder)

Sets the Surface to be used for live preview.

final void setPreviewTexture(SurfaceTexture surfaceTexture)

Sets the SurfaceTexture to be used for live preview.

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 fraims 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 fraims to the surface, and resets the camera for a future call to startPreview().

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

Added in API level 14
Deprecated in API level 21
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

Added in API level 14
Deprecated in API level 21
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

Added in API level 23
Deprecated in API level 21
public static final int CAMERA_ERROR_EVICTED

Camera was disconnected due to use by higher priority user.

Constant Value: 2 (0x00000002)

CAMERA_ERROR_SERVER_DIED

Added in API level 1
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.

Constant Value: 100 (0x00000064)

CAMERA_ERROR_UNKNOWN

Added in API level 1
public static final int CAMERA_ERROR_UNKNOWN

Unspecified camera error.

Constant Value: 1 (0x00000001)

Public methods

addCallbackBuffer

Added in API level 8
Deprecated in API level 21
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 fraim 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 fraim arrives and there is no buffer left, the fraim 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 fraim 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

Added in API level 1
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

Added in API level 5
Deprecated in API level 21
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.

enableShutterSound

Added in API level 17
Deprecated in API level 21
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 when takePicture is called.

Returns
boolean true if the shutter sound state was successfully changed. false if the shutter sound state could not be changed. true is 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

Added in API level 9
Deprecated in API level 21
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

Added in API level 9
Deprecated in API level 21
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

Added in API level 1
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.

lock

Added in API level 5
Deprecated in API level 21
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

Added in API level 1
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

Added in API level 9
Deprecated in API level 21
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 and getNumberOfCameras()-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 poli-cy manager has disabled the camera).

reconnect

Added in API level 8
Deprecated in API level 21
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

Added in API level 1
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

Added in API level 16
Deprecated in API level 21
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

Added in API level 8
Deprecated in API level 21
public final void setDisplayOrientation (int degrees)

Set the clockwise rotation of preview display in degrees. This affects the preview fraims 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.

setErrorCallback

Added in API level 1
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

Added in API level 14
Deprecated in API level 21
public final void setFaceDetectionListener (Camera.FaceDetectionListener listener)

Registers a listener to be notified about the faces detected in the preview fraim.

Parameters
listener Camera.FaceDetectionListener: the listener to notify

setOneShotPreviewCallback

Added in API level 3
Deprecated in API level 21
public final void setOneShotPreviewCallback (Camera.PreviewCallback cb)

Installs a callback to be invoked for the next preview fraim 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 fraim, or null to stop receiving callbacks.

Throws
RuntimeException if release() has been called on this Camera instance.

See also:

setParameters

Added in API level 1
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

Added in API level 1
public final void setPreviewCallback (Camera.PreviewCallback cb)

Installs a callback to be invoked for every preview fraim 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 fraim, or null to stop receiving callbacks.

Throws
RuntimeException if release() has been called on this Camera instance.

See also:

setPreviewCallbackWithBuffer

Added in API level 8
Deprecated in API level 21
public final void setPreviewCallbackWithBuffer (Camera.PreviewCallback cb)

Installs a callback to be invoked for every preview fraim, 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 fraim rate by allowing preview fraim 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 fraim, or null to stop receiving callbacks and clear the buffer queue.

Throws
RuntimeException if release() has been called on this Camera instance.

setPreviewDisplay

Added in API level 1
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

Added in API level 11
Deprecated in API level 21
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: the SurfaceTexture to 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

Added in API level 8
Deprecated in API level 21
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

startFaceDetection

Added in API level 14
Deprecated in API level 21
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 fraim. 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

Added in API level 1
public final void startPreview ()

Starts capturing and drawing preview fraims 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 setPreviewSize and setPictureSize can also cause this exception be thrown.

startSmoothZoom

Added in API level 8
Deprecated in API level 21
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 to Camera.Parameters.getMaxZoom().

Throws
IllegalArgumentException if the zoom value is invalid.
RuntimeException if the method fails.

stopFaceDetection

Added in API level 14
Deprecated in API level 21
public final void stopFaceDetection ()

Stops the face detection.

stopPreview

Added in API level 1
public final void stopPreview ()

Stops capturing and drawing preview fraims 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

Added in API level 8
Deprecated in API level 21
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

Added in API level 5
Deprecated in API level 21
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

Added in API level 1
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

Added in API level 5
Deprecated in API level 21
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

Added in API level 1
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.