Use texture-backed VideoFrane pipeline for Aura desktop capturing.

content/browser/media/capture/content_video_capture_device_core.h

 // Copyright 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.
 
 #ifndef CONTENT_BROWSER_MEDIA_CAPTURE_CONTENT_VIDEO_CAPTURE_DEVICE_CORE_H_
 #define CONTENT_BROWSER_MEDIA_CAPTURE_CONTENT_VIDEO_CAPTURE_DEVICE_CORE_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_checker.h"
 #include "content/browser/media/capture/video_capture_oracle.h"
 #include "content/common/content_export.h"
+#include "media/base/video_frame.h"
 #include "media/video/capture/video_capture_device.h"
 
 namespace media {
+class VideoCaptureParams;
 class VideoFrame;
 }  // namespace media
 
 namespace content {
 
-const int kMinFrameWidth = 2;
-const int kMinFrameHeight = 2;
-
 // Returns the nearest even integer closer to zero.
 template<typename IntType>
 IntType MakeEven(IntType x) {
   return x & static_cast<IntType>(-2);
 }
 
 // TODO(nick): Remove this once frame subscription is supported on Aura and
 // Linux.
 #if (defined(OS_WIN) || defined(OS_MACOSX)) || defined(USE_AURA)
 const bool kAcceleratedSubscriberIsSupported = true;
 #else
 const bool kAcceleratedSubscriberIsSupported = false;
 #endif
 
 class VideoCaptureMachine;
 
 // Thread-safe, refcounted proxy to the VideoCaptureOracle.  This proxy wraps
 // the VideoCaptureOracle, which decides which frames to capture, and a
 // VideoCaptureDevice::Client, which allocates and receives the captured
 // frames, in a lock to synchronize state between the two.
 class ThreadSafeCaptureOracle
     : public base::RefCountedThreadSafe<ThreadSafeCaptureOracle> {
  public:
   ThreadSafeCaptureOracle(scoped_ptr<media::VideoCaptureDevice::Client> client,
                           scoped_ptr<VideoCaptureOracle> oracle,
                           const media::VideoCaptureParams& params);
 
   // Called when a captured frame is available or an error has occurred.
-  // If |success| is true then the frame provided is valid and |timestamp|
-  // indicates when the frame was painted.
-  // If |success| is false, both the frame provided and |timestamp| are invalid.
-  typedef base::Callback<void(base::TimeTicks timestamp, bool success)>
-      CaptureFrameCallback;
+  // If |success| is true then |frame| is valid and |timestamp| indicates when
+  // the frame was painted.
+  // If |success| is false, all other parameters are invalid.

[Ami GONE FROM CHROMIUM, 2014/04/01 18:03:38]

Maybe make this the first param, then?

[hshi1, 2014/04/24 20:55:45]

It's a bit messy. See web_contents_video_capture_device.cc:
FrameSubscriber::ShouldCaptureFrame() where we return
base::Bind(capture_frame_cb, *storage) as type
content::RenderWidgetHostViewFrameSubscriber::DeliverFrameCallback, which
requires bool |frame_captured| as the last param. We'd either re-define
content::RenderWidgetHostViewFrameSubscriber::DeliverFrameCallback or add a
wrapper to swap the params.

[Ami GONE FROM CHROMIUM, 2014/04/24 21:05:28]

Yeah, not worth it.

+  typedef base::Callback<void(const scoped_refptr<media::VideoFrame>& frame,
+                              base::TimeTicks timestamp,
+                              bool success)> CaptureFrameCallback;
 
   bool ObserveEventAndDecideCapture(VideoCaptureOracle::Event event,
                                     base::TimeTicks event_time,
                                     scoped_refptr<media::VideoFrame>* storage,
                                     CaptureFrameCallback* callback);
 
   base::TimeDelta capture_period() const {
     return oracle_->capture_period();
   }
 
   // Returns the current capture resolution.
   gfx::Size GetCaptureSize() const;
 
   // Updates capture resolution based on the supplied source size and the
   // maximum frame size.
   void UpdateCaptureSize(const gfx::Size& source_size);
 
   // Stop new captures from happening (but doesn't forget the client).
   void Stop();
 
   // Signal an error to the client.
   void ReportError(const std::string& reason);
 
  private:
   friend class base::RefCountedThreadSafe<ThreadSafeCaptureOracle>;
   virtual ~ThreadSafeCaptureOracle();
 
   // Callback invoked on completion of all captures.
   void DidCaptureFrame(
+      int frame_number,
       const scoped_refptr<media::VideoCaptureDevice::Client::Buffer>& buffer,
       const scoped_refptr<media::VideoFrame>& frame,
-      int frame_number,
       base::TimeTicks timestamp,
       bool success);
 
   // Protects everything below it.
   mutable base::Lock lock_;
 
   // Recipient of our capture activity.
   scoped_ptr<media::VideoCaptureDevice::Client> client_;
 
   // Makes the decision to capture a frame.
   const scoped_ptr<VideoCaptureOracle> oracle_;
 
   // The video capture parameters used to construct the oracle proxy.
-  const media::VideoCaptureParams params_;
+  media::VideoCaptureParams params_;
 
   // Indicates if capture size has been updated after construction.
   bool capture_size_updated_;
 
-  // The current capturing resolution and frame rate.
-  gfx::Size capture_size_;
-  int frame_rate_;
+  // The current capturing format, as a media::VideoFrame::Format.
+  media::VideoFrame::Format video_frame_format_;
 };
 
 // Keeps track of the video capture source frames and executes copying on the
 // UI BrowserThread.
 class VideoCaptureMachine {
  public:
   VideoCaptureMachine() : started_(false) {}
   virtual ~VideoCaptureMachine() {}
 
   // This should only be checked on the UI thread.
   bool started() const { return started_; }
 
   // Starts capturing. Returns true if succeeded.
   // Must be run on the UI BrowserThread.
-  virtual bool Start(
-      const scoped_refptr<ThreadSafeCaptureOracle>& oracle_proxy) = 0;
+  virtual bool Start(const scoped_refptr<ThreadSafeCaptureOracle>& oracle_proxy,
+                     const media::VideoCaptureParams& params) = 0;
 
   // Stops capturing. Must be run on the UI BrowserThread.
   // |callback| is invoked after the capturing has stopped.
   virtual void Stop(const base::Closure& callback) = 0;
 
  protected:
   bool started_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(VideoCaptureMachine);
@@ skipping 54 matching lines @@
   // component of the/ system with direct access to |client_|.
   scoped_refptr<ThreadSafeCaptureOracle> oracle_proxy_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentVideoCaptureDeviceCore);
 };
 
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MEDIA_CAPTURE_CONTENT_VIDEO_CAPTURE_DEVICE_CORE_H_