ImageCapture: Implement takePhoto() for Mac AVFoundation

media/base/mac/avfoundation_glue.h

 // 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.
 
 // AVFoundation API is only introduced in Mac OS X > 10.6, and there is only one

[Robert Sesek, 2016/07/08 19:31:04]

Chrome now supports only 10.9+ so I think all this can be cleaned up. Maybe file
a bug for that and don't add new entries here?

[mcasas, 2016/07/08 21:39:28]

Hmmm there is already one, and I thought perkj@
wanted to take it, but he didn't. I propose adding
the methods here and removing this whole thing
separately. In any case, updated this comment.

[Robert Sesek, 2016/07/11 15:20:43]

It seems counter-productive to add code that just needs to be deleted later
(specifically CrAVCaptureStillImageOutput, I understand the methods on the
existing Cr objects), but I won't press it.

[mcasas, 2016/07/11 23:29:59]

Acknowledged.

 // build of Chromium, so the (potential) linking with AVFoundation has to happen
 // in runtime. For this to be clean, an AVFoundationGlue class is defined to try
 // and load these AVFoundation system libraries. If it succeeds, subsequent
 // clients can use AVFoundation via the rest of the classes declared in this
 // file.
 
 #ifndef MEDIA_BASE_MAC_AVFOUNDATION_GLUE_H_
 #define MEDIA_BASE_MAC_AVFOUNDATION_GLUE_H_
 
 #if defined(__OBJC__)
@@ skipping 28 matching lines @@
   static NSString* AVCaptureSessionRuntimeErrorNotification();
   static NSString* AVCaptureSessionDidStopRunningNotification();
   static NSString* AVCaptureSessionErrorKey();
 
   // Originally from AVVideoSettings.h but in global namespace.
   static NSString* AVVideoScalingModeKey();
   static NSString* AVVideoScalingModeResizeAspectFill();
 
   static Class AVCaptureSessionClass();
   static Class AVCaptureVideoDataOutputClass();
+  static Class AVCaptureStillImageOutputClass();
 #endif  // defined(__OBJC__)
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(AVFoundationGlue);
 };
 
 #if defined(__OBJC__)
 
 // Originally AVCaptureDevice and coming from AVCaptureDevice.h
 MEDIA_EXPORT
@@ skipping 24 matching lines @@
 - (Float64)maxFrameRate;
 
 @end
 
 MEDIA_EXPORT
 @interface CrAVCaptureInput : NSObject  // Originally from AVCaptureInput.h.
 @end
 
 MEDIA_EXPORT
 @interface CrAVCaptureOutput : NSObject  // Originally from AVCaptureOutput.h.
+
+- (NSArray*)connections;
+
 @end
 
 // Originally AVCaptureSession and coming from AVCaptureSession.h.
 MEDIA_EXPORT
 @interface CrAVCaptureSession : NSObject
 
 - (void)release;
 - (void)addInput:(CrAVCaptureInput*)input;
 - (void)removeInput:(CrAVCaptureInput*)input;
+- (NSArray*)outputs;
 - (void)addOutput:(CrAVCaptureOutput*)output;
 - (void)removeOutput:(CrAVCaptureOutput*)output;
 - (BOOL)isRunning;
 - (void)startRunning;
 - (void)stopRunning;
 
 @end
 
 // Originally AVCaptureConnection and coming from AVCaptureSession.h.
 MEDIA_EXPORT
@@ skipping 32 matching lines @@
 - (void)setSampleBufferDelegate:(id)sampleBufferDelegate
                           queue:(dispatch_queue_t)sampleBufferCallbackQueue;
 
 - (void)setAlwaysDiscardsLateVideoFrames:(BOOL)flag;
 - (void)setVideoSettings:(NSDictionary*)videoSettings;
 - (NSDictionary*)videoSettings;
 - (CrAVCaptureConnection*)connectionWithMediaType:(NSString*)mediaType;
 
 @end
 
+// Originally AVCaptureStillImageOutput and coming from AVCaptureOutput.h.
+MEDIA_EXPORT
+@interface CrAVCaptureStillImageOutput : CrAVCaptureOutput
+
+typedef void (^CompletionHandler)(CoreMediaGlue::CMSampleBufferRef, NSError*);
+- (void)
+captureStillImageAsynchronouslyFromConnection:(CrAVCaptureConnection*)connection
+                            completionHandler:(CompletionHandler)handler;
+
+@end
+
 // Class to provide access to class methods of AVCaptureDevice.
 MEDIA_EXPORT
 @interface AVCaptureDeviceGlue : NSObject
 
 + (NSArray*)devices;
 
 + (CrAVCaptureDevice*)deviceWithUniqueID:(NSString*)deviceUniqueID;
 
 @end
 
 // Class to provide access to class methods of AVCaptureDeviceInput.
 MEDIA_EXPORT
 @interface AVCaptureDeviceInputGlue : NSObject
 
 + (CrAVCaptureDeviceInput*)deviceInputWithDevice:(CrAVCaptureDevice*)device
                                            error:(NSError**)outError;
 
 @end
 
 #endif  // defined(__OBJC__)
 
 #endif  // MEDIA_BASE_MAC_AVFOUNDATION_GLUE_H_