Add PP_VideoFrame, PPB_VideoReader, and PPB_VideoWriter APIs to Pepper.

ppapi/api/ppb_video_writer.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_VideoWriter</code> struct for a video writer
+ * resource.
+ */
+
+ label Chrome {
+   M28 = 1.0
+ };
+
+/**
+ * The <code>PPB_VideoWriter</code> interface contains pointers to several
+ * functions for creating video writer resources and using them to generate
+ * streams of video frames.
+ */
+interface PPB_VideoWriter {
+  /**
+   * Creates a video writer resource.
+   *
+   * @param[in] instance A <code>PP_Instance</code> identifying one 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 writer.
+   *
+   * @param[in] resource A <code>PP_Resource</code> corresponding to a resource.
+   *
+   * @return A <code>PP_Bool</code> with <code>PP_TRUE</code> if the given
+   * resource is a video writer or <code>PP_FALSE</code> otherwise.
+   */
+  PP_Bool IsVideoWriter([in] PP_Resource resource);
+
+  /**
+   * Opens a video stream with the given id for writing.
+   *
+   * @param[in] writer A <code>PP_Resource</code> corresponding to a video
+   * writer resource.
+   * @param[in] stream_id A <code>PP_Var</code> holding a string uniquely
+   * identifying the stream. This string is application defined.
+   * @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 writer isn't a valid video writer.
+   * Returns PP_ERROR_INPROGRESS if the writer has already opened a stream.
+   */
+  int32_t Open([in] PP_Resource writer,
+               [in] PP_Var stream_id,
+               [in] PP_CompletionCallback callback);
+
+  /**
+   * Emits a frame of video to the writer's open stream.
+   *
+   * @param[in] writer A <code>PP_Resource</code> corresponding to a video
+   * writer resource.
+   * @param[in] frame A <code>PP_VideoFrame</code> holding a video frame to
+   * write to the open stream.

[bbudge, 2013/04/03 21:29:14]

We need a comment here about who owns the frame. Obviously if the plugin writes
to this it can cause coherency problems. Probably the plugin should release the
ImageData resource. For a similar case, see the PPB_Graphics2d ReplaceContents
function.

+   *
+   * @return An int32_t containing an error code from <code>pp_errors.h</code>.
+   * Returns PP_ERROR_BADRESOURCE if writer isn't a valid video writer.
+   * Returns PP_ERROR_FAILED if the writer has not opened a stream, if the video
+   * frame has an invalid image data resource, or if some other error occurs.
+   */
+  int32_t PutNextFrame([in] PP_Resource writer,
+                       [in] PP_VideoFrame frame);
+
+  /**
+   * Closes the writer's video stream.
+   *
+   * @param[in] writer A <code>PP_Resource</code> corresponding to a video
+   * writer resource.
+   */
+  void Close([in] PP_Resource writer);
+};
+