gecko-dev/dom/webidl/CameraControl.webidl

/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/* Camera regions are used to set focus and metering areas;
   the coordinates are referenced to the sensor:
     (-1000, -1000) is the top-left corner
     (1000, 1000) is the bottom-right corner
   The weight of the region can range from 0 to 1000. */
dictionary CameraRegion
{
  long top = -1000;
  long left = -1000;
  long bottom = 1000;
  long right = 1000;
  unsigned long weight = 1000;
};

/* The position information to record in the image header.
   'NaN' indicates the information is not available. */
dictionary CameraPosition
{
  unrestricted double latitude = NaN;
  unrestricted double longitude = NaN;
  unrestricted double altitude = NaN;
  unrestricted double timestamp = NaN;
};

/*
  Options for takePicture().
*/
dictionary CameraPictureOptions
{
  /* an object with a combination of 'height' and 'width' properties
     chosen from CameraCapabilities.pictureSizes */
  CameraSize pictureSize = null;

  /* one of the file formats chosen from
     CameraCapabilities.fileFormats */
  DOMString fileFormat = "";

  /* the rotation of the image in degrees, from 0 to 270 in
     steps of 90; this doesn't affect the image, only the
     rotation recorded in the image header.*/
  long rotation = 0;

  /* an object containing any or all of 'latitude', 'longitude',
     'altitude', and 'timestamp', used to record when and where
     the image was taken.  e.g.
     {
         latitude:  43.647118,
         longitude: -79.3943,
         altitude:  500
         // timestamp not specified, in this case, and
         // won't be included in the image header
     }

     can be null in the case where position information isn't
     available/desired.

     'altitude' is in metres; 'timestamp' is UTC, in seconds from
     January 1, 1970.
  */
  CameraPosition position = null;

  /* the number of seconds from January 1, 1970 UTC.  This can be
     different from the positional timestamp (above). */
  // XXXbz this should really accept a date too, no?
  long long dateTime = 0;
};

/* These properties affect the video recording preview, e.g.
      {
         profile: "1080p",
         rotation: 0
      }

   'profile' is one of the profiles returned by
   CameraCapabilities.recorderProfiles'; if this profile is missing,
   an arbitrary profile will be chosen.

   'rotation' is the degrees clockwise to rotate the preview; if
   this option is not supported, it will be ignored; if this option
   is missing, the default is 0.
*/
dictionary CameraRecorderOptions
{
  DOMString profile;
  long      rotation;
};

/* These properties affect the actual video recording, e.g.
      {
         rotation: 0,
         maxFileSizeBytes: 1024 * 1024,
         maxVideoLengthMs: 0
      }

   'rotation' is the degrees clockwise to rotate the recorded video; if
   this options is not supported, it will be ignored; if this option is
   missing, the default is 0.

   'maxFileSizeBytes' is the maximum size in bytes to which the recorded
   video file will be allowed to grow.

   'maxVideoLengthMs' is the maximum length in milliseconds to which the
   recorded video will be allowed to grow.

   if either 'maxFileSizeBytes' or 'maxVideoLengthMs' is missing, zero,
   or negative, that limit will be disabled.
*/
dictionary CameraStartRecordingOptions
{
  long      rotation = 0;
  long long maxFileSizeBytes = 0;
  long long maxVideoLengthMs = 0;
};

callback CameraSetConfigurationCallback = void (CameraConfiguration configuration);
callback CameraAutoFocusCallback = void (boolean focused);
callback CameraTakePictureCallback = void (Blob picture);
callback CameraStartRecordingCallback = void ();
callback CameraShutterCallback = void ();
callback CameraClosedCallback = void ();
callback CameraReleaseCallback = void ();
callback CameraRecorderStateChange = void (DOMString newState);
callback CameraPreviewStateChange = void (DOMString newState);

/*
    attributes here affect the preview, any pictures taken, and/or
    any video recorded by the camera.
*/
interface CameraControl : MediaStream
{
  [Constant, Cached]
  readonly attribute CameraCapabilities capabilities;

  /* one of the values chosen from capabilities.effects;
     default is "none" */
  [Throws]
  attribute DOMString       effect;

  /* one of the values chosen from capabilities.whiteBalanceModes;
     default is "auto" */
  [Throws]
  attribute DOMString       whiteBalanceMode;

  /* one of the values chosen from capabilities.sceneModes;
     default is "auto" */
  [Throws]
  attribute DOMString       sceneMode;

  /* one of the values chosen from capabilities.flashModes;
     default is "auto" */
  [Throws]
  attribute DOMString       flashMode;

  /* one of the values chosen from capabilities.focusModes;
     default is "auto", if supported, or "fixed" */
  [Throws]
  attribute DOMString       focusMode;

  /* one of the values chosen from capabilities.zoomRatios; other
     values will be rounded to the nearest supported value;
     default is 1.0 */
  [Throws]
  attribute double          zoom;

  /* an array of one or more objects that define where the
     camera will perform light metering, each defining the properties:
      {
          top: -1000,
          left: -1000,
          bottom: 1000,
          right: 1000,
          weight: 1000
      }

      'top', 'left', 'bottom', and 'right' all range from -1000 at
      the top-/leftmost of the sensor to 1000 at the bottom-/rightmost
      of the sensor.

      objects missing one or more of these properties will be ignored;
      if the array contains more than capabilities.maxMeteringAreas,
      extra areas will be ignored.

      this attribute can be set to null to allow the camera to determine
      where to perform light metering. */
  [Throws]
  attribute any             meteringAreas;

  /* an array of one or more objects that define where the camera will
     perform auto-focusing, with the same definition as meteringAreas.

     if the array contains more than capabilities.maxFocusAreas, extra
     areas will be ignored.

     this attribute can be set to null to allow the camera to determine
     where to focus. */
  [Throws]
  attribute any             focusAreas;

  /* focal length in millimetres */
  [Throws]
  readonly attribute double focalLength;

  /* the distances in metres to where the image subject appears to be
     in focus.  'focusDistanceOptimum' is where the subject will appear
     sharpest; the difference between 'focusDistanceFar' and
     'focusDistanceNear' is the image's depth of field.

     'focusDistanceFar' may be infinity. */
  [Throws]
  readonly attribute double focusDistanceNear;
  [Throws]
  readonly attribute double focusDistanceOptimum;
  [Throws]
  readonly attribute unrestricted double focusDistanceFar;

  /* 'compensation' is optional, and if missing, will
     set the camera to use automatic exposure compensation.

     acceptable values must range from minExposureCompensation
     to maxExposureCompensation in steps of stepExposureCompensation;
     invalid values will be rounded to the nearest valid value. */
  [Throws]
  void setExposureCompensation(optional double compensation);
  [Throws]
  readonly attribute unrestricted double exposureCompensation;

  /* the function to call on the camera's shutter event, to trigger
     a shutter sound and/or a visual shutter indicator. */
  attribute CameraShutterCallback? onShutter;

  /* the function to call when the camera hardware is closed
     by the underlying framework, e.g. when another app makes a more
     recent call to get the camera. */
  attribute CameraClosedCallback? onClosed;

  /* the function to call when the recorder changes state, either because
     the recording process encountered an error, or because one of the
     recording limits (see CameraStartRecordingOptions) was reached. */
  attribute CameraRecorderStateChange? onRecorderStateChange;

  /* the function to call when the viewfinder stops or starts,
     useful for synchronizing other UI elements. */
  attribute CameraPreviewStateChange? onPreviewStateChange;

  /* the size of the picture to be returned by a call to takePicture();
     an object with 'height' and 'width' properties that corresponds to
     one of the options returned by capabilities.pictureSizes. */
  [Throws]
  attribute any              pictureSize;

  /* the size of the thumbnail to be included in the picture returned
     by a call to takePicture(), assuming the chosen fileFormat supports
     one; an object with 'height' and 'width' properties that corresponds
     to one of the options returned by capabilities.pictureSizes.

     this setting should be considered a hint: the implementation will
     respect it when possible, and override it if necessary. */
  [Throws]
  attribute any             thumbnailSize;

  /* the angle, in degrees, that the image sensor is mounted relative
     to the display; e.g. if 'sensorAngle' is 270 degrees (or -90 degrees),
     then the preview stream needs to be rotated +90 degrees to have the
     same orientation as the real world. */
  readonly attribute long   sensorAngle;

  /* tell the camera to attempt to focus the image */
  [Throws]
  void autoFocus(CameraAutoFocusCallback onSuccess, optional CameraErrorCallback onError);

  /* capture an image and return it as a blob to the 'onSuccess' callback;
     if the camera supports it, this may be invoked while the camera is
     already recording video.

     invoking this function will stop the preview stream, which must be
     manually restarted (e.g. by calling .play() on it). */
  [Throws]
  void takePicture(CameraPictureOptions aOptions,
                   CameraTakePictureCallback onSuccess,
                   optional CameraErrorCallback onError);

  /* start recording video; 'aOptions' is a
     CameraStartRecordingOptions object. */
  [Throws]
  void startRecording(CameraStartRecordingOptions aOptions,
                      DeviceStorage storageArea,
                      DOMString filename,
                      CameraStartRecordingCallback onSuccess,
                      optional CameraErrorCallback onError);

  /* stop precording video. */
  [Throws]
  void stopRecording();

  /* call in or after the takePicture() onSuccess callback to
     resume the camera preview stream. */
  [Throws]
  void resumePreview();

  /* release the camera so that other applications can use it; you should
     probably call this whenever the camera is not longer in the foreground
     (depending on your usage model).

     the callbacks are optional, unless you really need to know when
     the hardware is ultimately released.

     once this is called, the camera control object is to be considered
     defunct; a new instance will need to be created to access the camera. */
  [Throws]
  void release(optional CameraReleaseCallback onSuccess,
               optional CameraErrorCallback onError);

  /* changes the camera configuration on the fly;
     'configuration' is of type CameraConfiguration.

     XXXmikeh the 'configuration' argument needs to be optional, else
     the WebIDL compiler throws: "WebIDL.WebIDLError: error: Dictionary
     argument or union argument containing a dictionary not followed by
     a required argument must be optional"
  */
  [Throws]
  void setConfiguration(optional CameraConfiguration configuration,
                        optional CameraSetConfigurationCallback onSuccess,
                        optional CameraErrorCallback onError);
};