ppapi/cpp/video_frame.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef PPAPI_CPP_VIDEO_FRAME_H_
   6 #define PPAPI_CPP_VIDEO_FRAME_H_
   7
   8 #include "ppapi/c/pp_time.h"
   9 #include "ppapi/c/pp_video_frame.h"
  10 #include "ppapi/cpp/completion_callback.h"
  11 #include "ppapi/cpp/image_data.h"
  12 #include "ppapi/cpp/pass_ref.h"
  13
  14 /// @file
  15 /// This file defines the video frame struct used by video readers and writers.
  16
  17 namespace pp {
  18
  19 // VideoFrame ------------------------------------------------------------------
  20
  21 /// The <code>VideoFrame</code> class represents a frame of video in a stream.
  22 class VideoFrame {
  23  public:
  24   /// Default constructor for creating a <code>VideoFrame</code> object.
  25   VideoFrame();
  26
  27   /// Constructor that takes an existing <code>PP_VideoFrame</code> structure.
  28   /// The 'image_data' PP_Resource field in the structure will be managed by
  29   /// this instance.
  30   VideoFrame(PassRef, const PP_VideoFrame& pp_video_frame);
  31
  32   /// Constructor that takes an existing <code>ImageData</code> instance and
  33   /// a timestamp.
  34   VideoFrame(const ImageData& image_data, PP_TimeTicks timestamp);
  35
  36   /// The copy constructor for <code>VideoFrame</code>.
  37   ///
  38   /// @param[in] other A reference to a <code>VideoFrame</code>.
  39   VideoFrame(const VideoFrame& other);
  40
  41   ~VideoFrame();
  42
  43   VideoFrame& operator=(const VideoFrame& other);
  44
  45   const PP_VideoFrame& pp_video_frame() const {
  46     return video_frame_;
  47   }
  48
  49   ImageData image_data() const {
  50     return image_data_;
  51   }
  52   void set_image_data(const ImageData& image_data) {
  53     image_data_ = image_data;
  54     // The assignment above manages the underlying PP_Resources. Copy the new
  55     // one into our internal video frame struct.
  56     video_frame_.image_data = image_data_.pp_resource();
  57   }
  58
  59   PP_TimeTicks timestamp() const { return video_frame_.timestamp; }
  60   void set_timestamp(PP_TimeTicks timestamp) {
  61     video_frame_.timestamp = timestamp;
  62   }
  63
  64  private:
  65   ImageData image_data_;  // This manages the PP_Resource in video_frame_.
  66   PP_VideoFrame video_frame_;
  67 };
  68
  69 namespace internal {
  70
  71 // A specialization of CallbackOutputTraits to provide the callback system the
  72 // information on how to handle pp::VideoFrame. This converts PP_VideoFrame to
  73 // pp::VideoFrame when passing to the plugin, and specifically manages the
  74 // PP_Resource embedded in the video_frame_ field.
  75 template<>
  76 struct CallbackOutputTraits<pp::VideoFrame> {
  77   typedef PP_VideoFrame* APIArgType;
  78   typedef PP_VideoFrame StorageType;
  79
  80   static inline APIArgType StorageToAPIArg(StorageType& t) {
  81     return &t;
  82   }
  83
  84   static inline pp::VideoFrame StorageToPluginArg(StorageType& t) {
  85     return pp::VideoFrame(PASS_REF, t);
  86   }
  87 };
  88
  89 }  // namespace internal
  90
  91 }  // namespace pp
  92
  93 #endif  // PPAPI_CPP_VIDEO_FRAME_H_