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// Copyright 2013 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 MEDIA_VIDEO_CAPTURE_MAC_VIDEO_CAPTURE_DEVICE_AVFOUNDATION_MAC_H_
#define MEDIA_VIDEO_CAPTURE_MAC_VIDEO_CAPTURE_DEVICE_AVFOUNDATION_MAC_H_
#import <Foundation/Foundation.h>
#import "base/mac/scoped_nsobject.h"
#include "base/synchronization/lock.h"
#include "base/threading/thread_checker.h"
#import "media/base/mac/avfoundation_glue.h"
#include "media/base/video_capture_types.h"
#import "media/capture/video/mac/platform_video_capturing_mac.h"
#include "media/capture/video/video_capture_device.h"
namespace media {
class VideoCaptureDeviceMac;
}
@class CrAVCaptureDevice;
@class CrAVCaptureSession;
@class CrAVCaptureVideoDataOutput;
// Class used by VideoCaptureDeviceMac (VCDM) for video capture using
// AVFoundation API. This class lives inside the thread created by its owner
// VCDM.
//
// * Clients (VCDM) should call +deviceNames to fetch the list of devices
// available in the system; this method returns the list of device names that
// have to be used with -setCaptureDevice:.
// * Previous to any use, clients (VCDM) must call -initWithFrameReceiver: to
// initialise an object of this class and register a |frameReceiver_|.
// * Frame receiver registration or removal can also happen via explicit call
// to -setFrameReceiver:. Re-registrations are safe and allowed, even during
// capture using this method.
// * Method -setCaptureDevice: must be called at least once with a device
// identifier from +deviceNames. Creates all the necessary AVFoundation
// objects on first call; it connects them ready for capture every time.
// This method should not be called during capture (i.e. between
// -startCapture and -stopCapture).
// * -setCaptureWidth:height:frameRate: is called if a resolution or frame rate
// different than the by default one set by -setCaptureDevice: is needed.
// This method should not be called during capture. This method must be
// called after -setCaptureDevice:.
// * -startCapture registers the notification listeners and starts the
// capture. The capture can be stop using -stopCapture. The capture can be
// restarted and restoped multiple times, reconfiguring or not the device in
// between.
// * -setCaptureDevice can be called with a |nil| value, case in which it stops
// the capture and disconnects the library objects. This step is not
// necessary.
// * Deallocation of the library objects happens gracefully on destruction of
// the VideoCaptureDeviceAVFoundation object.
//
//
@interface VideoCaptureDeviceAVFoundation
: NSObject<CrAVCaptureVideoDataOutputSampleBufferDelegate,
PlatformVideoCapturingMac> {
@private
// The following attributes are set via -setCaptureHeight:width:frameRate:.
int frameWidth_;
int frameHeight_;
float frameRate_;
base::Lock lock_; // Protects concurrent setting and using of frameReceiver_.
media::VideoCaptureDeviceMac* frameReceiver_; // weak.
base::scoped_nsobject<CrAVCaptureSession> captureSession_;
// |captureDevice_| is an object coming from AVFoundation, used only to be
// plugged in |captureDeviceInput_| and to query for session preset support.
CrAVCaptureDevice* captureDevice_;
// |captureDeviceInput_| is owned by |captureSession_|.
CrAVCaptureDeviceInput* captureDeviceInput_;
base::scoped_nsobject<CrAVCaptureVideoDataOutput> captureVideoDataOutput_;
base::ThreadChecker main_thread_checker_;
base::ThreadChecker callback_thread_checker_;
}
// Returns a dictionary of capture devices with friendly name and unique id.
+ (NSDictionary*)deviceNames;
// Retrieve the capture supported formats for a given device |name|.
+ (void)getDevice:(const media::VideoCaptureDevice::Name&)name
supportedFormats:(media::VideoCaptureFormats*)formats;
// Initializes the instance and the underlying capture session and registers the
// frame receiver.
- (id)initWithFrameReceiver:(media::VideoCaptureDeviceMac*)frameReceiver;
// Sets the frame receiver.
- (void)setFrameReceiver:(media::VideoCaptureDeviceMac*)frameReceiver;
// Sets which capture device to use by name, retrieved via |deviceNames|. Once
// the deviceId is known, the library objects are created if needed and
// connected for the capture, and a by default resolution is set. If deviceId is
// nil, then the eventual capture is stopped and library objects are
// disconnected. Returns YES on sucess, NO otherwise. This method should not be
// called during capture.
- (BOOL)setCaptureDevice:(NSString*)deviceId;
// Configures the capture properties for the capture session and the video data
// output; this means it MUST be called after setCaptureDevice:. Return YES on
// success, else NO.
- (BOOL)setCaptureHeight:(int)height
width:(int)width
frameRate:(float)frameRate;
// Starts video capturing and register the notification listeners. Must be
// called after setCaptureDevice:, and, eventually, also after
// setCaptureHeight:width:frameRate:. Returns YES on sucess, NO otherwise.
- (BOOL)startCapture;
// Stops video capturing and stops listening to notifications.
- (void)stopCapture;
@end
#endif // MEDIA_VIDEO_CAPTURE_MAC_VIDEO_CAPTURE_DEVICE_AVFOUNDATION_MAC_H_
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