com.twilio.video

Class CameraCapturer

java.lang.Object

com.twilio.video.CameraCapturer

All Implemented Interfaces:

VideoCapturer

public class CameraCapturer
extends java.lang.Object
implements VideoCapturer

The CameraCapturer class is used to provide video frames for a LocalVideoTrack from a given cameraId. The frames are provided via the preview API of Camera.

This class represents an implementation of a VideoCapturer interface. Although public, these methods are not meant to be invoked directly.

Note: This capturer can be reused, but cannot be shared across multiple LocalVideoTracks simultaneously.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	CameraCapturer.Error
static interface	CameraCapturer.Listener Interface that provides events and errors related to CameraCapturer.

Field Summary

Fields

Modifier and Type	Field and Description
static int	ERROR_CAMERA_FREEZE
static int	ERROR_CAMERA_PERMISSION_NOT_GRANTED
static int	ERROR_CAMERA_SERVER_STOPPED
static int	ERROR_CAMERA_SWITCH_FAILED
static int	ERROR_UNKNOWN
static int	ERROR_UNSUPPORTED_SOURCE

Constructor Summary

Constructors

Constructor and Description
CameraCapturer(android.content.Context context, java.lang.String cameraId) Constructs a CameraCapturer instance.
CameraCapturer(android.content.Context context, java.lang.String cameraId, CameraCapturer.Listener listener) Constructs a CameraCapturer instance.

Method Summary

Modifier and Type	Method and Description
void	dispose() This method provides an optional step to perform a final cleanup.
java.lang.String	getCameraId() Returns the currently set cameraID.
void	initialize(SurfaceTextureHelper surfaceTextureHelper, android.content.Context context, CapturerObserver capturerObserver) This function is used to initialize the camera thread, the android application context, and the capture observer.
boolean	isScreencast() Indicates that the camera capturer is not a screen cast.
void	startCapture(int width, int height, int framerate) Start capturing frames in a format that is as close as possible to width x height and framerate.
void	stopCapture() Stops all frames being captured.
void	switchCamera(java.lang.String newCameraId) Switches the current cameraId.
boolean	updateCameraParameters(CameraParameterUpdater cameraParameterUpdater) Schedules a camera parameter update.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.twilio.video.VideoCapturer

changeCaptureFormat, getCaptureFormat

Field Detail

ERROR_CAMERA_FREEZE

public static final int ERROR_CAMERA_FREEZE

See Also:

Constant Field Values

ERROR_CAMERA_SERVER_STOPPED

public static final int ERROR_CAMERA_SERVER_STOPPED

See Also:

Constant Field Values

ERROR_UNSUPPORTED_SOURCE

public static final int ERROR_UNSUPPORTED_SOURCE

See Also:

Constant Field Values

ERROR_CAMERA_PERMISSION_NOT_GRANTED

public static final int ERROR_CAMERA_PERMISSION_NOT_GRANTED

See Also:

Constant Field Values

ERROR_CAMERA_SWITCH_FAILED

public static final int ERROR_CAMERA_SWITCH_FAILED

See Also:

Constant Field Values

ERROR_UNKNOWN

public static final int ERROR_UNKNOWN

See Also:

Constant Field Values

Constructor Detail

CameraCapturer

public CameraCapturer(@NonNull
                      android.content.Context context,
                      @NonNull
                      java.lang.String cameraId)

Constructs a CameraCapturer instance.

Parameters:

context - application context

cameraId - unique identifier of the camera device to open that must be specified in Camera1Enumerator.getDeviceNames()

CameraCapturer

public CameraCapturer(@NonNull
                      android.content.Context context,
                      @NonNull
                      java.lang.String cameraId,
                      @Nullable
                      CameraCapturer.Listener listener)

Constructs a CameraCapturer instance.

Parameters:

context - application context

cameraId - unique identifier of the camera device to open that must be specified in Camera1Enumerator.getDeviceNames()

listener - an optional listener of camera capturer events

Method Detail

isScreencast

public boolean isScreencast()

Indicates that the camera capturer is not a screen cast.

Specified by:

isScreencast in interface VideoCapturer

Returns:

true if-and-only-if this is a screen capturer.

initialize

public void initialize(@NonNull
                       SurfaceTextureHelper surfaceTextureHelper,
                       @NonNull
                       android.content.Context context,
                       @NonNull
                       CapturerObserver capturerObserver)

Description copied from interface: VideoCapturer

This function is used to initialize the camera thread, the android application context, and the capture observer. It will be called only once and before any startCapture() request. The camera thread is guaranteed to be valid until dispose() is called. If the VideoCapturer wants to deliver texture frames, it should do this by rendering on the SurfaceTexture in surfaceTextureHelper, register itself as a listener, and forward the frames to CapturerObserver.onFrameCaptured(). The caller still has ownership of surfaceTextureHelper and is responsible for making sure surfaceTextureHelper.dispose() is called. This also means that the caller can reuse the SurfaceTextureHelper to initialize a new VideoCapturer once the previous VideoCapturer has been disposed.

Specified by:

initialize in interface VideoCapturer

startCapture

public void startCapture(int width,
                         int height,
                         int framerate)

Description copied from interface: VideoCapturer

Start capturing frames in a format that is as close as possible to width x height and framerate.

Specified by:

startCapture in interface VideoCapturer

stopCapture

public void stopCapture()

Stops all frames being captured. The Camera interface should be available for use upon completion.

Note: This method is not meant to be invoked directly.

Specified by:

stopCapture in interface VideoCapturer

dispose

public void dispose()

Description copied from interface: VideoCapturer

This method provides an optional step to perform a final cleanup.

Specified by:

dispose in interface VideoCapturer

getCameraId

@NonNull
public java.lang.String getCameraId()

Returns the currently set cameraID.

switchCamera

public void switchCamera(@NonNull
                         java.lang.String newCameraId)

Switches the current cameraId. This method can be invoked while capturing frames or not.

Parameters:

newCameraId - the new camera id.

updateCameraParameters

public boolean updateCameraParameters(@NonNull
                                      CameraParameterUpdater cameraParameterUpdater)

Schedules a camera parameter update. The current camera's Camera.Parameters will be provided for modification via CameraParameterUpdater.apply(Camera.Parameters). Any changes to the parameters will be applied after the invocation of this callback. This method can be invoked while capturing frames or not.

The following snippet demonstrates how to turn on the flash of a camera while capturing.

     // Create camera capturer
     CameraCapturer cameraCapturer = new CameraCapturer(context, cameraId, null);

     // Start camera capturer
     LocalVideoTrack cameraVideoTrack = LocalVideoTrack.create(context, true, cameraCapturer);

     // Schedule camera parameter update
     cameraCapturer.updateCameraParameters(new CameraParameterUpdater() {
         @Override
         public void apply(Camera.Parameters cameraParameters) {
             // Ensure camera supports flash and turn on
             if (cameraParameters.getFlashMode() != null) {
                  cameraParameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
             }
         }
     });
 

Parameters:

cameraParameterUpdater - camera parameter updater that receives current camera parameters for modification.

Returns:

true if update was scheduled or false if an update is pending or could not be scheduled.