content/renderer/pepper/pepper_video_source_host.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 CONTENT_RENDERER_PEPPER_PEPPER_VIDEO_SOURCE_HOST_H_
   6 #define CONTENT_RENDERER_PEPPER_PEPPER_VIDEO_SOURCE_HOST_H_
   7
   8 #include "base/compiler_specific.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/memory/weak_ptr.h"
  12 #include "base/threading/thread_checker.h"
  13 #include "content/common/content_export.h"
  14 #include "content/renderer/media/video_source_handler.h"
  15 #include "ppapi/c/pp_time.h"
  16 #include "ppapi/c/ppb_image_data.h"
  17 #include "ppapi/host/host_message_context.h"
  18 #include "ppapi/host/resource_host.h"
  19
  20 struct PP_ImageDataDesc;
  21
  22 namespace content {
  23
  24 class PPB_ImageData_Impl;
  25 class RendererPpapiHost;
  26
  27 class CONTENT_EXPORT PepperVideoSourceHost : public ppapi::host::ResourceHost {
  28  public:
  29   PepperVideoSourceHost(RendererPpapiHost* host,
  30                         PP_Instance instance,
  31                         PP_Resource resource);
  32
  33   ~PepperVideoSourceHost() override;
  34
  35   int32_t OnResourceMessageReceived(
  36       const IPC::Message& msg,
  37       ppapi::host::HostMessageContext* context) override;
  38
  39  private:
  40   // This helper object receives frames on a video worker thread and passes
  41   // them on to us.
  42   class FrameReceiver : public FrameReaderInterface,
  43                         public base::RefCountedThreadSafe<FrameReceiver> {
  44    public:
  45     explicit FrameReceiver(const base::WeakPtr<PepperVideoSourceHost>& host);
  46
  47     // FrameReaderInterface implementation.
  48     void GotFrame(const scoped_refptr<media::VideoFrame>& frame) override;
  49
  50    private:
  51     friend class base::RefCountedThreadSafe<FrameReceiver>;
  52     ~FrameReceiver() override;
  53
  54     base::WeakPtr<PepperVideoSourceHost> host_;
  55     // |thread_checker_| is bound to the main render thread.
  56     base::ThreadChecker thread_checker_;
  57   };
  58
  59   friend class FrameReceiver;
  60
  61   int32_t OnHostMsgOpen(ppapi::host::HostMessageContext* context,
  62                         const std::string& stream_url);
  63   int32_t OnHostMsgGetFrame(ppapi::host::HostMessageContext* context);
  64   int32_t OnHostMsgClose(ppapi::host::HostMessageContext* context);
  65
  66   // Sends the reply to a GetFrame message from the plugin. A reply is always
  67   // sent and last_frame_, reply_context_, and get_frame_pending_ are all reset.
  68   void SendGetFrameReply();
  69   // Sends the reply to a GetFrame message from the plugin in case of an error.
  70   void SendGetFrameErrorReply(int32_t error);
  71
  72   void Close();
  73
  74   ppapi::host::ReplyMessageContext reply_context_;
  75
  76   scoped_ptr<VideoSourceHandler> source_handler_;
  77   scoped_refptr<FrameReceiver> frame_receiver_;
  78   std::string stream_url_;
  79   scoped_refptr<media::VideoFrame> last_frame_;
  80   // An internal frame buffer to avoid reallocations. It is only allocated if
  81   // scaling is needed.
  82   scoped_refptr<media::VideoFrame> scaled_frame_;
  83   bool get_frame_pending_;
  84   // We use only one ImageData resource in order to avoid allocating
  85   // shared memory repeatedly. We send the same one each time the plugin
  86   // requests a frame. For this to work, the plugin must finish using
  87   // the ImageData it receives prior to calling GetFrame, and not access
  88   // the ImageData until it gets its next callback to GetFrame.
  89   scoped_refptr<PPB_ImageData_Impl> shared_image_;
  90   PP_ImageDataDesc shared_image_desc_;
  91
  92   base::WeakPtrFactory<PepperVideoSourceHost> weak_factory_;
  93
  94   DISALLOW_COPY_AND_ASSIGN(PepperVideoSourceHost);
  95 };
  96
  97 }  // namespace content
  98
  99 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_VIDEO_SOURCE_HOST_H_