Rename PPAPI Video Stream APIs.

ppapi/api/private/ppb_video_source_private.idl

 /* Copyright (c) 2013 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.
  */
 
 /**
- * This file defines the <code>PPB_VideoReader</code> struct for a video reader
- * resource.
+ * This file defines the <code>PPB_VideoSource_Private</code> interface for a
+ * video source resource. A video source receives video frames from a
+ * MediaStream video track.
  */
 
  label Chrome {
    M28 = 0.1
  };
 
 /**
- * The <code>PPB_VideoReader</code> interface contains pointers to several
- * functions for creating video reader resources and using them to consume
- * streams of video frames.
+ * The <code>PPB_VideoSource_Private</code> interface contains pointers to
+ * several functions for creating video source resources and using them to
+ * receive video frames from a MediaStream in the browser.
  */
-interface PPB_VideoReader {
+interface PPB_VideoSource_Private {
   /**
-   * Creates a video reader resource.
+   * Creates a video source resource.
    *
-   * @param[in] instance A <code>PP_Instance</code> identifying one instance
-   * of a module.
+   * @param[in] instance A <code>PP_Instance</code> identifying an instance of
+   * a module.
    *
    * @return A <code>PP_Resource</code> with a nonzero ID on success or zero on
    * failure. Failure means the instance was invalid.
    */
   PP_Resource Create([in] PP_Instance instance);
 
   /**
-   * Determines if a given resource is a video reader.
+   * Determines if a resource is a video source resource.
    *
-   * @param[in] resource A <code>PP_Resource</code> corresponding to a 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 a video reader or <code>PP_FALSE</code> otherwise.
+   * resource is a video source resource or <code>PP_FALSE</code> otherwise.
    */
-  PP_Bool IsVideoReader([in] PP_Resource resource);
+  PP_Bool IsVideoSource([in] PP_Resource resource);
 
   /**
-   * Opens a video stream with the given id for reading.
+   * Opens a video source to emit frames.
    *
-   * @param[in] reader A <code>PP_Resource</code> corresponding to a video
-   * reader resource.
-   * @param[in] stream_id A <code>PP_Var</code> holding a string uniquely
-   * identifying the stream. This string is application defined.
+   * @param[in] source A <code>PP_Resource</code> corresponding to a video
+   * source resource.
+   * @param[in] stream_url A <code>PP_Var</code> string holding a URL
+   * identifying a MediaStream.
    * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
    * completion of Open().
    *
-   * @return An int32_t containing an error code from <code>pp_errors.h</code>.
-   * Returns PP_ERROR_BADRESOURCE if reader isn't a valid video reader.
-   * Returns PP_ERROR_INPROGRESS if the reader has already opened a stream.
+   * @return An int32_t containing a result code from <code>pp_errors.h</code>.
+   * Returns PP_ERROR_BADRESOURCE if source isn't a valid video source.
+   * Returns PP_ERROR_INPROGRESS if source is already open.
+   * Returns PP_ERROR_FAILED if the MediaStream doesn't exist or if there is
+   * some other browser error.
    */
-  int32_t Open([in] PP_Resource reader,
-               [in] PP_Var stream_id,
+  int32_t Open([in] PP_Resource source,
+               [in] PP_Var stream_url,
                [in] PP_CompletionCallback callback);
 
   /**
-   * Gets the next frame of video from the reader's open stream. The image data
-   * resource returned in the frame will have its reference count incremented by
-   * one and must be managed by the plugin.
+   * Passes a frame from the video source to the plugin.
+   * The image data resource inside the returned frame will have its reference
+   * count incremented by one and must be managed by the plugin.
    *
-   * @param[in] reader A <code>PP_Resource</code> corresponding to a video
-   * reader resource.
-   * @param[out] frame A <code>PP_VideoFrame</code> to hold a video frame to
-   * read from the open stream.
+   * @param[in] source A <code>PP_Resource</code> corresponding to a video
+   * source resource.
+   * @param[out] frame A <code>PP_VideoFrame_Private</code> to hold a video
+   * frame from the source.
    * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
    * completion of GetNextFrame().
    *
-   * @return An int32_t containing an error code from <code>pp_errors.h</code>.
-   * Returns PP_ERROR_BADRESOURCE if reader isn't a valid video reader.
-   * Returns PP_ERROR_FAILED if the reader has not opened a stream, if the video
-   * frame has an invalid image data resource, or if some other error occurs.
+   * @return An int32_t containing a result code from <code>pp_errors.h</code>.
+   * Returns PP_ERROR_BADRESOURCE if source isn't a valid video source.
+   * Returns PP_ERROR_FAILED if the source is not open, or if some other
+   * browser error occurs.
    */
-  int32_t GetFrame([in] PP_Resource reader,
-                   [out] PP_VideoFrame frame,
-                   [in] PP_CompletionCallback callback);
+  int32_t EmitFrame([in] PP_Resource source,

[Ronghua Wu (Left Chromium), 2013/04/25 18:22:48]

Don't we get frame here instead of "emit"?

[bbudge, 2013/04/25 18:30:08]

This does return a frame, but the VideoSource resource 'emits' it. It all
depends on whether you're thinking about it from the plugin's or the object's
point of view. I searched for some existing terminology but didn't find anything
too compelling. I will defer to the video folks on naming here. Justin?

+                    [out] PP_VideoFrame_Private frame,
+                    [in] PP_CompletionCallback callback);
 
   /**
-   * Closes the reader's video stream.
+   * Closes the video source.
    *
-   * @param[in] reader A <code>PP_Resource</code> corresponding to a video
-   * reader resource.
+   * @param[in] source A <code>PP_Resource</code> corresponding to a video
+   * source resource.
    */
-  void Close([in] PP_Resource reader);
+  void Close([in] PP_Resource source);
 };