move //media/capture to //device/capture

media/capture/video/video_capture_device.h

-// Copyright (c) 2012 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.
-//
-// VideoCaptureDevice is the abstract base class for realizing video capture
-// device support in Chromium. It provides the interface for OS dependent
-// implementations.
-// The class is created and functions are invoked on a thread owned by
-// VideoCaptureManager. Capturing is done on other threads, depending on the OS
-// specific implementation.
-
-#ifndef MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_DEVICE_H_
-#define MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_DEVICE_H_
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include <list>
-#include <memory>
-#include <string>
-
-#include "base/callback.h"
-#include "base/files/file.h"
-#include "base/logging.h"
-#include "base/memory/ref_counted.h"
-#include "base/single_thread_task_runner.h"
-#include "base/time/time.h"
-#include "build/build_config.h"
-#include "media/base/video_capture_types.h"
-#include "media/base/video_frame.h"
-#include "media/capture/capture_export.h"
-#include "media/capture/video/scoped_result_callback.h"
-#include "media/capture/video/video_capture_device_descriptor.h"
-#include "media/mojo/interfaces/image_capture.mojom.h"
-#include "mojo/public/cpp/bindings/array.h"
-#include "ui/gfx/gpu_memory_buffer.h"
-
-namespace tracked_objects {
-class Location;
-}  // namespace tracked_objects
-
-namespace media {
-
-class CAPTURE_EXPORT VideoCaptureDevice {
- public:
-
-  // Interface defining the methods that clients of VideoCapture must have. It
-  // is actually two-in-one: clients may implement OnIncomingCapturedData() or
-  // ReserveOutputBuffer() + OnIncomingCapturedVideoFrame(), or all of them.
-  // All clients must implement OnError().
-  class CAPTURE_EXPORT Client {
-   public:
-    // Memory buffer returned by Client::ReserveOutputBuffer().
-    class CAPTURE_EXPORT Buffer {
-     public:
-      virtual ~Buffer() = 0;
-      virtual int id() const = 0;
-      virtual gfx::Size dimensions() const = 0;
-      virtual size_t mapped_size() const = 0;
-      virtual void* data(int plane) = 0;
-      void* data() { return data(0); }
-      virtual ClientBuffer AsClientBuffer(int plane) = 0;
-#if defined(OS_POSIX) && !(defined(OS_MACOSX) && !defined(OS_IOS))
-      virtual base::FileDescriptor AsPlatformFile() = 0;
-#endif
-    };
-
-    virtual ~Client() {}
-
-    // Captured a new video frame, data for which is pointed to by |data|.
-    //
-    // The format of the frame is described by |frame_format|, and is assumed to
-    // be tightly packed. This method will try to reserve an output buffer and
-    // copy from |data| into the output buffer. If no output buffer is
-    // available, the frame will be silently dropped. |reference_time| is
-    // system clock time when we detect the capture happens, it is used for
-    // Audio/Video sync, not an exact presentation time for playout, because it
-    // could contain noise. |timestamp| measures the ideal time span between the
-    // first frame in the stream and the current frame; however, the time source
-    // is determined by the platform's device driver and is often not the system
-    // clock, or even has a drift with respect to system clock.
-    virtual void OnIncomingCapturedData(const uint8_t* data,
-                                        int length,
-                                        const VideoCaptureFormat& frame_format,
-                                        int clockwise_rotation,
-                                        base::TimeTicks reference_time,
-                                        base::TimeDelta timestamp) = 0;
-
-    // Reserve an output buffer into which contents can be captured directly.
-    // The returned Buffer will always be allocated with a memory size suitable
-    // for holding a packed video frame with pixels of |format| format, of
-    // |dimensions| frame dimensions. It is permissible for |dimensions| to be
-    // zero; in which case the returned Buffer does not guarantee memory
-    // backing, but functions as a reservation for external input for the
-    // purposes of buffer throttling.
-    //
-    // The output buffer stays reserved and mapped for use until the Buffer
-    // object is destroyed or returned.
-    virtual std::unique_ptr<Buffer> ReserveOutputBuffer(
-        const gfx::Size& dimensions,
-        VideoPixelFormat format,
-        VideoPixelStorage storage) = 0;
-
-    // Captured new video data, held in |frame| or |buffer|, respectively for
-    // OnIncomingCapturedVideoFrame() and  OnIncomingCapturedBuffer().
-    //
-    // In both cases, as the frame is backed by a reservation returned by
-    // ReserveOutputBuffer(), delivery is guaranteed and will require no
-    // additional copies in the browser process.
-    // See OnIncomingCapturedData for details of |reference_time| and
-    // |timestamp|.
-    virtual void OnIncomingCapturedBuffer(
-        std::unique_ptr<Buffer> buffer,
-        const VideoCaptureFormat& frame_format,
-        base::TimeTicks reference_time,
-        base::TimeDelta timestamp) = 0;
-    virtual void OnIncomingCapturedVideoFrame(
-        std::unique_ptr<Buffer> buffer,
-        const scoped_refptr<VideoFrame>& frame) = 0;
-
-    // Attempts to reserve the same Buffer provided in the last call to one of
-    // the OnIncomingCapturedXXX() methods. This will fail if the content of the
-    // Buffer has not been preserved, or if the |dimensions|, |format|, or
-    // |storage| disagree with how it was reserved via ReserveOutputBuffer().
-    // When this operation fails, nullptr will be returned.
-    virtual std::unique_ptr<Buffer> ResurrectLastOutputBuffer(
-        const gfx::Size& dimensions,
-        VideoPixelFormat format,
-        VideoPixelStorage storage) = 0;
-
-    // An error has occurred that cannot be handled and VideoCaptureDevice must
-    // be StopAndDeAllocate()-ed. |reason| is a text description of the error.
-    virtual void OnError(const tracked_objects::Location& from_here,
-                         const std::string& reason) = 0;
-
-    // VideoCaptureDevice requests the |message| to be logged.
-    virtual void OnLog(const std::string& message) {}
-
-    // Returns the current buffer pool utilization, in the range 0.0 (no buffers
-    // are in use by producers or consumers) to 1.0 (all buffers are in use).
-    virtual double GetBufferPoolUtilization() const = 0;
-  };
-
-  virtual ~VideoCaptureDevice();
-
-  // Prepares the video capturer for use. StopAndDeAllocate() must be called
-  // before the object is deleted.
-  virtual void AllocateAndStart(const VideoCaptureParams& params,
-                                std::unique_ptr<Client> client) = 0;
-
-  // In cases where the video capturer self-pauses (e.g., a screen capturer
-  // where the screen's content has not changed in a while), consumers may call
-  // this to request a "refresh frame" be delivered to the Client.  This is used
-  // in a number of circumstances, such as:
-  //
-  //   1. An additional consumer of video frames is starting up and requires a
-  //      first frame (as opposed to not receiving a frame for an indeterminate
-  //      amount of time).
-  //   2. A few repeats of the same frame would allow a lossy video encoder to
-  //      improve the video quality of unchanging content.
-  //
-  // The default implementation is a no-op. VideoCaptureDevice implementations
-  // are not required to honor this request, especially if they do not
-  // self-pause and/or if honoring the request would cause them to exceed their
-  // configured maximum frame rate. Any VideoCaptureDevice that does self-pause,
-  // however, should provide an implementation of this method that makes
-  // reasonable attempts to honor these requests.
-  virtual void RequestRefreshFrame() {}
-
-  // Deallocates the video capturer, possibly asynchronously.
-  //
-  // This call requires the device to do the following things, eventually: put
-  // hardware into a state where other applications could use it, free the
-  // memory associated with capture, and delete the |client| pointer passed into
-  // AllocateAndStart.
-  //
-  // If deallocation is done asynchronously, then the device implementation must
-  // ensure that a subsequent AllocateAndStart() operation targeting the same ID
-  // would be sequenced through the same task runner, so that deallocation
-  // happens first.
-  virtual void StopAndDeAllocate() = 0;
-
-  // Retrieve the photo capabilities of the device (e.g. zoom levels etc).
-  using GetPhotoCapabilitiesCallback =
-      ScopedResultCallback<base::Callback<void(mojom::PhotoCapabilitiesPtr)>>;
-  virtual void GetPhotoCapabilities(GetPhotoCapabilitiesCallback callback);
-
-  using SetPhotoOptionsCallback =
-      ScopedResultCallback<base::Callback<void(bool)>>;
-  virtual void SetPhotoOptions(mojom::PhotoSettingsPtr settings,
-                               SetPhotoOptionsCallback callback);
-
-  // Asynchronously takes a photo, possibly reconfiguring the capture objects
-  // and/or interrupting the capture flow. Runs |callback| on the thread
-  // where TakePhoto() is called, if the photo was successfully taken.
-  using TakePhotoCallback =
-      ScopedResultCallback<base::Callback<void(mojom::BlobPtr blob)>>;
-  virtual void TakePhoto(TakePhotoCallback callback);
-
-  // Gets the power line frequency, either from the params if specified by the
-  // user or from the current system time zone.
-  PowerLineFrequency GetPowerLineFrequency(
-      const VideoCaptureParams& params) const;
-
- private:
-  // Gets the power line frequency from the current system time zone if this is
-  // defined, otherwise returns 0.
-  PowerLineFrequency GetPowerLineFrequencyForLocation() const;
-};
-
-}  // namespace media
-
-#endif  // MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_DEVICE_H_