Introduce a client minimum picture pool size

ppapi/api/ppb_video_decoder.idl

 /* Copyright (c) 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.
  */
 
 /**
  * This file defines the <code>PPB_VideoDecoder</code> interface.
  */
 
 [generate_thunk]
 
 label Chrome {
   /** Though not labeled 'channel=dev', 0.1 is a still a 'Dev' only API. */
   M36 = 0.1,
   M39 = 0.2,
-  M40 = 1.0
+  M40 = 1.0,
+  M44 = 1.1

[bbudge, 2015/07/22 02:02:47]

Usually we expose a new API to 'Dev' channel and review it before promoting to
'Stable'.

 };
 
 /**
  * Video decoder interface.
  *
  * Typical usage:
  * - Call Create() to create a new video decoder resource.
  * - Call Initialize() to initialize it with a 3d graphics context and the
  *   desired codec profile.
  * - Call Decode() continuously (waiting for each previous call to complete) to
@@ skipping 87 matching lines @@
    */
   [version = 0.2]
   int32_t Initialize(
       [in] PP_Resource video_decoder,
       [in] PP_Resource graphics3d_context,
       [in] PP_VideoProfile profile,
       [in] PP_HardwareAcceleration acceleration,
       [in] PP_CompletionCallback callback);
 
   /**
+   * Initializes a video decoder resource. This should be called after Create()
+   * and before any other functions.
+   *
+   * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
+   * decoder.
+   * @param[in] graphics3d_context A <code>PPB_Graphics3D</code> resource to use
+   * during decoding.
+   * @param[in] profile A <code>PP_VideoProfile</code> specifying the video
+   * codec profile.
+   * @param[in] acceleration A <code>PP_HardwareAcceleration</code> specifying
+   * whether to use a hardware accelerated or a software implementation.
+   * @param[in] min_picture_count A count of pictures the plugin would like to
+   * have in flight. This is effectively the number of times the plugin can
+   * call GetPicture() and get a decoded frame without calling
+   * RecyclePicture(). The decoder has its own internal minimum count, and will
+   * take the larger of its internal and this value. A client that doesn't care
+   * can therefore just pass in zero for this argument.
+   * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
+   * completion.
+   *
+   * @return An int32_t containing an error code from <code>pp_errors.h</code>.
+   * Returns PP_ERROR_NOTSUPPORTED if video decoding is not available, or the
+   * requested profile is not supported. In this case, the client may call
+   * Initialize() again with different parameters to find a good configuration.
+   * Returns PP_ERROR_BADARGUMENT if the requested minimum picture count is
+   * unreasonably large.
+   */
+  [version = 1.1]
+  int32_t Initialize(
+      [in] PP_Resource video_decoder,
+      [in] PP_Resource graphics3d_context,
+      [in] PP_VideoProfile profile,
+      [in] PP_HardwareAcceleration acceleration,
+      [in] uint32_t min_picture_count,
+      [in] PP_CompletionCallback callback);
+
+  /**
    * Decodes a bitstream buffer. Copies |size| bytes of data from the plugin's
    * |buffer|. The plugin should wait until the decoder signals completion by
    * returning PP_OK or by running |callback| before calling Decode() again.
    *
    * In general, each bitstream buffer should contain a demuxed bitstream frame
    * for the selected video codec. For example, H264 decoders expect to receive
    * one AnnexB NAL unit, including the 4 byte start code prefix, while VP8
    * decoders expect to receive a bitstream frame without the IVF frame header.
    *
    * If the call to Decode() eventually results in a picture, the |decode_id|
@@ skipping 131 matching lines @@
    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
    * completion.
    *
    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
    * Returns PP_ERROR_FAILED if the decoder isn't initialized.
    */
   int32_t Reset(
       [in] PP_Resource video_decoder,
       [in] PP_CompletionCallback callback);
 };