PPAPI: implement GetSupportedPreviewSizes

ppapi/api/private/ppb_image_capture_private.idl

 /* Copyright 2014 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /**
  * Defines the <code>PPB_ImageCapture_Private</code> interface. Used for
  * acquiring a single still image from a camera source.
  */
 
 [generate_thunk]
 
 label Chrome {
-  M39 = 0.1
+  M40 = 0.1
 };
 
 /**
  * Callback function for <code>PPB_ImageCapture_Private.CaptureStillImage
  * </code> to indicate the image has been captured from the sensor. This is a
  * good opportunity to play a shutter sound or give other feedback of camera
  * operation. This will occur after the image was captured, but before the
  * actual data is available.
  *
  * Parameters:
- *  |user_data| The same pointer that was passed into <code>
- *  PPB_ImageCapture_Private.Create()</code>.
  *  |sequence_id| The sequence ID of the image capture, same as the one from
  *  CaptureStillImage.
  */
 typedef void PPB_ImageCapture_Private_ShutterCallback(
-    [inout] mem_t user_data,
-    [in] int64_t sequence_id);
+    [in] uint64_t sequence_id);

[wuchengli, 2015/01/19 14:05:03]

Please revert all the changes not related to GetSupportedPreviewSizes. For
example, ShutterCallback, uesr_data, ErrorCallback, ReuseBuffers,
CaptureStillImage, and etc.

[Justin Chuang, 2015/01/26 15:00:50]

Will update to this CL later.

 
 /**
  * Callback function for <code>PPB_ImageCapture_Private.CaptureStillImage
  * </code> to deliver a preview image. The client can use this to show the
  * captured image. See <code>PPB_ImageCapture_Private.CaptureStillImage
  * </code> for more information.
  *
  * Parameters:
- *  |user_data| The same pointer that was passed into <code>
- *  PPB_ImageCapture_Private.Create()</code>.
  *  |sequence_id| The sequence ID of the image capture, same as the one from
  *  CaptureStillImage.
  *  |preview| A <code>PP_Resource</code> corresponding to a VideoFrame
  *  resource used to store the preview image.
  */
 typedef void PPB_ImageCapture_Private_PreviewCallback(
-    [inout] mem_t user_data,
-    [in] int64_t sequence_id,
+    [in] uint64_t sequence_id,
     [in] PP_Resource preview);
 
 /**
  * Callback function for <code>PPB_ImageCapture_Private.CaptureStillImage
  * </code> to deliver a still JPEG image. See <code>
  * PPB_ImageCapture_Private.CaptureStillImage</code> for more information.
  *
  * Parameters:
- *  |user_data| The same pointer that was passed into <code>
- *  PPB_ImageCapture_Private.Create()</code>.
  *  |sequence_id| The sequence ID of the image capture, same as the one from
  *  CaptureStillImage.
  *  |jpeg| A <code>PP_Resource</code> corresponding to a VideoFrame
  *  resource used to store the JPEG image.
  */
 typedef void PPB_ImageCapture_Private_JpegCallback(
-    [inout] mem_t user_data,
-    [in] int64_t sequence_id,
+    [in] uint64_t sequence_id,
     [in] PP_Resource jpeg);
 
 /**
  * Callback function for <code>PPB_ImageCapture_Private.CaptureStillImage
  * </code> to indicate the image capture has failed.
  *
  * Parameters:
- *  |user_data| The same pointer that was passed into <code>
- *  PPB_ImageCapture_Private.Create()</code>.
  *  |sequence_id| The sequence ID of the image capture, same as the one from
  *  CaptureStillImage.
  *  |int32_t| An error code from <code>pp_errors.h</code>.
  */
 typedef void PPB_ImageCapture_Private_ErrorCallback(
-    [inout] mem_t user_data,
-    [in] int64_t sequence_id,
+    [in] uint64_t sequence_id,
     [in] int32_t pp_error);
 
 /**
  * To capture a still image with this class, use the following steps.
  * 1. Get a PPB_ImageCapture_Private object by Create().
- * 2. Call GetCameraCapabilities to get the supported preview sizes.
- * 3. For optimal performance, set one of the supported preview size as the
+ * 2. Open() the device with camera source ID.
+ * 3. Call GetCameraCapabilities() to get the supported preview sizes.
+ * 4. For optimal performance, set one of the supported preview size as the
  *    constraints of getUserMedia. Use the created MediaStreamVideoTrack for
  *    camera previews.
- * 4. Set the same preview size and other settings by SetConfig.
- * 5. Call CaptureStillImage to capture a still image. Play the shutter sound in
- *    the shutter callback. The image from the preview callback can be used for
- *    display. JPEG image will be returned to the JPEG callback.
+ * 5. Set the same preview size and other settings by SetConfig().
+ * 6. Call CaptureStillImage() to capture a still image. Play the shutter sound
+ *    in the shutter callback. The image from the preview callback can be used
+ *    for displaying preview. JPEG image will be returned by the JPEG callback.
  */
 interface PPB_ImageCapture_Private {
   /**
    * Creates a PPB_ImageCapture_Private resource.
    *
    * @param[in] instance A <code>PP_Instance</code> identifying one instance
    * of a module.
-   * @param[in] camera_source_id A <code>PP_Var</code> identifying a camera
-   * source. The type is string. The ID can be obtained from
-   * MediaStreamTrack.getSources() or MediaStreamVideoTrack.id. If a
-   * MediaStreamVideoTrack is associated with the same source and the track
-   * is closed, this PPB_ImageCapture_Private object can still do image capture.
-   * @param[in] error_callback A <code>PPB_ImageCapture_Private_ErrorCallback
-   * </code> callback to indicate the image capture has failed.
-   * @param[inout] user_data An opaque pointer that will be passed to the
-   * callbacks of PPB_ImageCapture_Private.
    *
    * @return A <code>PP_Resource</code> corresponding to a
    * PPB_ImageCapture_Private resource if successful, 0 if failed.
    */
-  PP_Resource Create([in] PP_Instance instance,
-                     [in] PP_Var camera_source_id,
-                     [in] PPB_ImageCapture_Private_ErrorCallback error_callback,
-                     [inout] mem_t user_data);
+  PP_Resource Create([in] PP_Instance instance);
 
   /**
    * Determines if a resource is an image capture resource.
    *
    * @param[in] resource The <code>PP_Resource</code> to test.
    *
    * @return A <code>PP_Bool</code> with <code>PP_TRUE</code> if the given
    * resource is an image capture resource or <code>PP_FALSE</code>
    * otherwise.
    */
   PP_Bool IsImageCapture([in] PP_Resource resource);
 
   /**
+   * Opens a video capture device.
+   *
+   * @param[in] image_capture A <code>PP_Resource</code> corresponding to an
+   * image capture resource.
+   * @param[in] device_id A <code>PP_Var</code> identifying a camera device. The
+   * type is string. The ID can be obtained from MediaStreamTrack.getSources()
+   * or MediaStreamVideoTrack.id. If a MediaStreamVideoTrack is associated with
+   * the same source and the track is closed, this PPB_ImageCapture_Private
+   * object can still do image capture.
+   * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
+   * completion of <code>Open()</code>.
+   *
+   * @return An error code from <code>pp_errors.h</code>.
+   */
+  int32_t Open(
+      [in] PP_Resource image_capture,
+      [in] PP_Var device_id,
+      [in] PP_CompletionCallback callback);
+
+  /**
    * Disconnects from the camera and cancels all pending capture requests.
    * After this returns, no callbacks will be called. If <code>
    * PPB_ImageCapture_Private</code> is destroyed and is not closed yet, this
    * function will be automatically called. Calling this more than once has no
    * effect.
    *
    * @param[in] image_capture A <code>PP_Resource</code> corresponding to an
    * image capture resource.
-   * @param[in] callback <code>PP_CompletionCallback</code> to be called upon
-   * completion of <code>Close()</code>.
-   *
-   * @return An int32_t containing a result code from <code>pp_errors.h</code>.
    */
-  int32_t Close([in] PP_Resource resource,
-                [in] PP_CompletionCallback callback);
+  void Close([in] PP_Resource image_capture);
 
   /**
    * Sets the configuration of the image capture.
    * If <code>SetConfig()</code> is not called, default settings will be used.
    *
    * @param[in] image_capture A <code>PP_Resource</code> corresponding to an
    * image capture resource.
    * @param[in] config A <code>PP_ImageCaptureConfig_Private</code> object.
    * @param[in] callback <code>PP_CompletionCallback</code> to be called upon
-   * completion of <code>SetConfig()</code>.
+   * completion of <code>SetConfig()</code>. This callback will only run if the
+   * return code is <code>PP_OK_COMPLETIONPENDING</code>.
    *
    * @return An int32_t containing a result code from <code>pp_errors.h</code>.
    * Returns <code>PP_ERROR_INPROGRESS</code> if there is a pending call of
    * <code>SetConfig()</code> or <code>CaptureStillImage()</code>.
    * If an error is returned, the configuration will not be changed.
    */
   int32_t SetConfig([in] PP_Resource image_capture,
                     [in] PP_Resource config,
                     [in] PP_CompletionCallback callback);
 
   /**
    * Gets the configuration of the image capture.
    *
    * @param[in] image_capture A <code>PP_Resource</code> corresponding to an
    * image capture resource.
    * @param[out] config A <code>PP_ImageCaptureConfig_Private</code> for storing
    * the current image capture config on success. Otherwise, the values will not
    * be changed.
    * @param[in] callback <code>PP_CompletionCallback</code> to be called upon
-   * completion of <code>GetConfig()</code>.
+   * completion of <code>GetConfig()</code>. This callback will only run if the
+   * return code is <code>PP_OK_COMPLETIONPENDING</code>.
    *
    * @return An int32_t containing a result code from <code>pp_errors.h</code>.
    */
   int32_t GetConfig([in] PP_Resource image_capture,
                     [out] PP_Resource config,
                     [in] PP_CompletionCallback callback);
 
   /**
    * Gets the camera capabilities.
    *
    * The camera capabilities do not change for a given camera source.
    *
    * @param[in] image_capture A <code>PP_Resource</code> corresponding to an
    * image capture resource.
    * @param[out] capabilities A <code>PPB_CameraCapabilities_Private</code> for
    * storing the image capture capabilities on success. Otherwise, the value
    * will not be changed.
    * @param[in] callback <code>PP_CompletionCallback</code> to be called upon
-   * completion of <code>GetCameraCapabilities()</code>.
+   * completion of <code>GetCameraCapabilities()</code>. This callback will only
+   * run if the return code is <code>PP_OK_COMPLETIONPENDING</code>.
    *
    * @return An int32_t containing a result code from <code>pp_errors.h</code>.
    */
   int32_t GetCameraCapabilities([in] PP_Resource image_capture,
                                 [out] PP_Resource capabilities,
                                 [in] PP_CompletionCallback callback);
 
   /**
+   * Allows the browser to reuse preview buffer and JPEG buffer that was
+   * previously sent by |preview_calback| and |jpeg_callback| registered in
+   * <code>PPB_ImageCapture_Private.CaptureStillImage()</code>.
+   *
+   * @return An int32_t containing a result code from <code>pp_errors.h</code>.
+   */
+  int32_t ReuseBuffers(
+      [in] PP_Resource image_capture);
+
+  /**
    * Captures a still JPEG image from the camera.
    *
    * Triggers an asynchronous image capture. The camera will initiate a series
    * of callbacks to the application as the image capture progresses. The
    * callbacks will be invoked in the order of shutter callback, preview
    * callback, and JPEG callback. 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 preview callback occurs when a scaled, fully
    * processed preview image is available. The JPEG callback occurs when the
    * compressed image is available. If there is an error after the capture is in
-   * progress, the error callback passed to <code>
-   * PPB_ImageCapture_Private.Create()</code> will be invoked. All the callbacks
-   * are invoked by the thread that calls this function.
+   * progress, the error callback will be invoked. All the callbacks are invoked
+   * by the thread that calls this function.
    *
    * The size of the preview image in preview callback is determined by
    * <code>PPB_ImageCaptureConfig_Private.SetPreviewSize</code>. The format is
    * decided by the camera and can be got from <code>PPB_VideoFrame.GetFormat
    * </code>. The size of the JPEG image is determined by <code>
    * PPB_ImageCaptureConfig_Private.SetJpegSize</code>.
    *
    * The camera may need to stop and re-start streaming during image capture. If
    * some MediaStreamVideoTrack are associated with the camera source, they will
    * receive mute and unmute events. The mute event will be received before all
    * the callbacks. The unmute event will be received after all the callbacks.
    * The preview image will not be sent to the video tracks associated with the
    * camera.
    *
    * @param[in] image_capture A <code>PP_Resource</code> corresponding to an
    * image capture resource.
    * @param[in] shutter_callback A <code>
    * PPB_ImageCapture_Private_ShutterCallback</code> callback to indicate the
    * image has been taken.
    * @param[in] preview_callback A <code>
    * PPB_ImageCapture_Private_PreviewCallback</code> callback to return a
    * preview of the captured image.
    * @param[in] jpeg_callback A <code>
    * PPB_ImageCapture_Private_JpegCallback</code> callback to return captured
    * JPEG image.
+   * @param[in] error_callback A <code>PPB_ImageCapture_Private_ErrorCallback
+   * </code> callback to indicate <code>CaptureStillImage()</code> has failed.
    * @param[out] sequence_id The sequence ID is a unique monotonically
    * increasing value starting from 0, incremented every time a new request like
    * image capture is submitted.
    *
    * @return An int32_t containing a result code from <code>pp_errors.h</code>.
    * PP_OK means the callbacks will be triggered. Other values mean the
    * callbacks will not be triggered.
    */
   int32_t CaptureStillImage(
       [in] PP_Resource image_capture,
       [in] PPB_ImageCapture_Private_ShutterCallback shutter_callback,
       [in] PPB_ImageCapture_Private_PreviewCallback preview_callback,
       [in] PPB_ImageCapture_Private_JpegCallback jpeg_callback,
-      [out] int64_t sequence_id);
+      [in] PPB_ImageCapture_Private_ErrorCallback error_callback,
+      [out] uint64_t sequence_id);
 };