media/capture/video/mac/video_capture_device_decklink_mac.h

   1 // Copyright 2014 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 // Implementation of VideoCaptureDevice class for Blackmagic video capture
   6 // devices by using the DeckLink SDK.
   7
   8 #ifndef MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_DECKLINK_MAC_H_
   9 #define MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_DECKLINK_MAC_H_
  10
  11 #include "media/capture/video/video_capture_device.h"
  12
  13 #import <Foundation/Foundation.h>
  14
  15 #include "base/synchronization/lock.h"
  16 #include "base/threading/thread_checker.h"
  17
  18 namespace {
  19 class DeckLinkCaptureDelegate;
  20 }  // namespace
  21
  22 namespace media {
  23
  24 // Extension of VideoCaptureDevice to create and manipulate Blackmagic devices.
  25 // Creates a reference counted |decklink_capture_delegate_| that does all the
  26 // DeckLink SDK configuration and capture work while holding a weak reference to
  27 // us for sending back frames, logs and error messages.
  28 class MEDIA_EXPORT VideoCaptureDeviceDeckLinkMac : public VideoCaptureDevice {
  29  public:
  30   // Gets the names of all DeckLink video capture devices connected to this
  31   // computer, as enumerated by the DeckLink SDK. To allow the user to choose
  32   // exactly which capture format she wants, we enumerate as many cameras as
  33   // capture formats.
  34   static void EnumerateDevices(VideoCaptureDevice::Names* device_names);
  35
  36   // Gets the supported formats of a particular device attached to the system,
  37   // identified by |device|. Formats are retrieved from the DeckLink SDK.
  38   // Following the enumeration, each camera will have only one capability.
  39   static void EnumerateDeviceCapabilities(
  40       const VideoCaptureDevice::Name& device,
  41       VideoCaptureFormats* supported_formats);
  42
  43   explicit VideoCaptureDeviceDeckLinkMac(const Name& device_name);
  44   ~VideoCaptureDeviceDeckLinkMac() override;
  45
  46   // Copy of VideoCaptureDevice::Client::OnIncomingCapturedData(). Used by
  47   // |decklink_capture_delegate_| to forward captured frames.
  48   void OnIncomingCapturedData(const uint8* data,
  49                               size_t length,
  50                               const VideoCaptureFormat& frame_format,
  51                               int rotation,  // Clockwise.
  52                               base::TimeTicks timestamp);
  53
  54   // Forwarder to VideoCaptureDevice::Client::OnError().
  55   void SendErrorString(const std::string& reason);
  56
  57   // Forwarder to VideoCaptureDevice::Client::OnLog().
  58   void SendLogString(const std::string& message);
  59
  60  private:
  61   // VideoCaptureDevice implementation.
  62   void AllocateAndStart(const VideoCaptureParams& params,
  63                         scoped_ptr<VideoCaptureDevice::Client> client) override;
  64   void StopAndDeAllocate() override;
  65
  66   // Protects concurrent setting and using of |client_|.
  67   base::Lock lock_;
  68   scoped_ptr<VideoCaptureDevice::Client> client_;
  69
  70   // Reference counted handle to the DeckLink capture delegate, ref counted by
  71   // the DeckLink SDK as well.
  72   scoped_refptr<DeckLinkCaptureDelegate> decklink_capture_delegate_;
  73
  74   // Checks for Device (a.k.a. Audio) thread.
  75   base::ThreadChecker thread_checker_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(VideoCaptureDeviceDeckLinkMac);
  78 };
  79
  80 }  // namespace media
  81
  82 #endif  // MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_DECKLINK_MAC_H_