packages/camera/ios/Classes/CameraPlugin.m - mirrors/plugins - Git at Google

 #import "CameraPlugin.h"
 #import <AVFoundation/AVFoundation.h>
 #import <libkern/OSAtomic.h>

 @interface NSError (FlutterError)
 @property(readonly, nonatomic) FlutterError *flutterError;
 @end

 @implementation NSError (FlutterError)
 - (FlutterError *)flutterError {
   return [FlutterError errorWithCode:[NSString stringWithFormat:@"Error %d", (int)self.code]
                              message:self.domain
                              details:self.localizedDescription];
 }
 @end

 @interface FLTSavePhotoDelegate : NSObject<AVCapturePhotoCaptureDelegate>
 @property(readonly, nonatomic) NSString *path;
 @property(readonly, nonatomic) FlutterResult result;

 - initWithPath:(NSString *)filename result:(FlutterResult)result;
 @end

 @implementation FLTSavePhotoDelegate {
   /// Used to keep the delegate alive until didFinishProcessingPhotoSampleBuffer.
   FLTSavePhotoDelegate *selfReference;
 }

 - initWithPath:(NSString *)path result:(FlutterResult)result {
   self = [super init];
   NSAssert(self, @"super init cannot be nil");
   _path = path;
   _result = result;
   selfReference = self;
   return self;
 }

 - (void)captureOutput:(AVCapturePhotoOutput *)output
     didFinishProcessingPhotoSampleBuffer:(CMSampleBufferRef)photoSampleBuffer
                 previewPhotoSampleBuffer:(CMSampleBufferRef)previewPhotoSampleBuffer
                         resolvedSettings:(AVCaptureResolvedPhotoSettings *)resolvedSettings
                          bracketSettings:(AVCaptureBracketedStillImageSettings *)bracketSettings
                                    error:(NSError *)error {
   selfReference = nil;
   if (error) {
     _result([error flutterError]);
     return;
   }
   NSData *data = [AVCapturePhotoOutput
       JPEGPhotoDataRepresentationForJPEGSampleBuffer:photoSampleBuffer
                             previewPhotoSampleBuffer:previewPhotoSampleBuffer];
   // TODO(sigurdm): Consider writing file asynchronously.
   bool success = [data writeToFile:_path atomically:YES];
   if (!success) {
     _result([FlutterError errorWithCode:@"IOError" message:@"Unable to write file" details:nil]);
     return;
   }
   _result(nil);
 }
 @end

 @interface FLTCam : NSObject<FlutterTexture, AVCaptureVideoDataOutputSampleBufferDelegate,
                              AVCaptureAudioDataOutputSampleBufferDelegate, FlutterStreamHandler>
 @property(readonly, nonatomic) int64_t textureId;
 @property(nonatomic, copy) void (^onFrameAvailable)();
 @property(nonatomic) FlutterEventChannel *eventChannel;
 @property(nonatomic) FlutterEventSink eventSink;
 @property(readonly, nonatomic) AVCaptureSession *captureSession;
 @property(readonly, nonatomic) AVCaptureDevice *captureDevice;
 @property(readonly, nonatomic) AVCapturePhotoOutput *capturePhotoOutput;
 @property(readonly, nonatomic) AVCaptureVideoDataOutput *captureVideoOutput;
 @property(readonly, nonatomic) AVCaptureInput *captureVideoInput;
 @property(readonly) CVPixelBufferRef volatile latestPixelBuffer;
 @property(readonly, nonatomic) CGSize previewSize;
 @property(readonly, nonatomic) CGSize captureSize;
 @property(strong, nonatomic) AVAssetWriter *videoWriter;
 @property(strong, nonatomic) AVAssetWriterInput *videoWriterInput;
 @property(strong, nonatomic) AVAssetWriterInput *audioWriterInput;
 @property(strong, nonatomic) AVAssetWriterInputPixelBufferAdaptor *assetWriterPixelBufferAdaptor;
 @property(strong, nonatomic) AVCaptureVideoDataOutput *videoOutput;
 @property(strong, nonatomic) AVCaptureAudioDataOutput *audioOutput;
 @property(assign, nonatomic) BOOL isRecording;
 @property(assign, nonatomic) BOOL isAudioSetup;
 - (instancetype)initWithCameraName:(NSString *)cameraName
                   resolutionPreset:(NSString *)resolutionPreset
                              error:(NSError **)error;
 - (void)start;
 - (void)stop;
 - (void)startVideoRecordingAtPath:(NSString *)path result:(FlutterResult)result;
 - (void)stopVideoRecordingWithResult:(FlutterResult)result;
 - (void)captureToFile:(NSString *)filename result:(FlutterResult)result;
 @end

 @implementation FLTCam
 - (instancetype)initWithCameraName:(NSString *)cameraName
                   resolutionPreset:(NSString *)resolutionPreset
                              error:(NSError **)error {
   self = [super init];
   NSAssert(self, @"super init cannot be nil");
   _captureSession = [[AVCaptureSession alloc] init];
   AVCaptureSessionPreset preset;
   if ([resolutionPreset isEqualToString:@"high"]) {
     preset = AVCaptureSessionPresetHigh;
   } else if ([resolutionPreset isEqualToString:@"medium"]) {
     preset = AVCaptureSessionPresetMedium;
   } else {
     NSAssert([resolutionPreset isEqualToString:@"low"], @"Unknown resolution preset %@",
              resolutionPreset);
     preset = AVCaptureSessionPresetLow;
   }
   _captureSession.sessionPreset = preset;
   _captureDevice = [AVCaptureDevice deviceWithUniqueID:cameraName];
   NSError *localError = nil;
   _captureVideoInput =
       [AVCaptureDeviceInput deviceInputWithDevice:_captureDevice error:&localError];
   if (localError) {
     *error = localError;
     return nil;
   }
   CMVideoDimensions dimensions =
       CMVideoFormatDescriptionGetDimensions([[_captureDevice activeFormat] formatDescription]);
   _previewSize = CGSizeMake(dimensions.width, dimensions.height);

   _captureVideoOutput = [AVCaptureVideoDataOutput new];
   _captureVideoOutput.videoSettings =
       @{(NSString *)kCVPixelBufferPixelFormatTypeKey : @(kCVPixelFormatType_32BGRA) };
   [_captureVideoOutput setAlwaysDiscardsLateVideoFrames:YES];
   [_captureVideoOutput setSampleBufferDelegate:self queue:dispatch_get_main_queue()];

   AVCaptureConnection *connection =
       [AVCaptureConnection connectionWithInputPorts:_captureVideoInput.ports
                                              output:_captureVideoOutput];
   if ([_captureDevice position] == AVCaptureDevicePositionFront) {
     connection.videoMirrored = YES;
   }
   connection.videoOrientation = AVCaptureVideoOrientationPortrait;
   [_captureSession addInputWithNoConnections:_captureVideoInput];
   [_captureSession addOutputWithNoConnections:_captureVideoOutput];
   [_captureSession addConnection:connection];
   _capturePhotoOutput = [AVCapturePhotoOutput new];
   [_captureSession addOutput:_capturePhotoOutput];
   return self;
 }

 - (void)start {
   [_captureSession startRunning];
 }

 - (void)stop {
   [_captureSession stopRunning];
 }

 - (void)captureToFile:(NSString *)path result:(FlutterResult)result {
   AVCapturePhotoSettings *settings = [AVCapturePhotoSettings photoSettings];
   [_capturePhotoOutput
       capturePhotoWithSettings:settings
                       delegate:[[FLTSavePhotoDelegate alloc] initWithPath:path result:result]];
 }

 - (void)captureOutput:(AVCaptureOutput *)output
     didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
            fromConnection:(AVCaptureConnection *)connection {
   if (output == _captureVideoOutput) {
     CVPixelBufferRef newBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
     CFRetain(newBuffer);
     CVPixelBufferRef old = _latestPixelBuffer;
     while (!OSAtomicCompareAndSwapPtrBarrier(old, newBuffer, (void **)&_latestPixelBuffer)) {
       old = _latestPixelBuffer;
     }
     if (old != nil) {
       CFRelease(old);
     }
     if (_onFrameAvailable) {
       _onFrameAvailable();
     }
   }
   if (!CMSampleBufferDataIsReady(sampleBuffer)) {
     _eventSink(@{
       @"event" : @"error",
       @"errorDescription" : @"sample buffer is not ready. Skipping sample"
     });
     return;
   }
   if (_isRecording) {
     if (_videoWriter.status == AVAssetWriterStatusFailed) {
       _eventSink(@{
         @"event" : @"error",
         @"errorDescription" : [NSString stringWithFormat:@"%@", _videoWriter.error]
       });
       return;
     }
     CMTime lastSampleTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
     if (_videoWriter.status != AVAssetWriterStatusWriting) {
       [_videoWriter startWriting];
       [_videoWriter startSessionAtSourceTime:lastSampleTime];
     }
     if (output == _captureVideoOutput) {
       [self newVideoSample:sampleBuffer];
     } else {
       [self newAudioSample:sampleBuffer];
     }
   }
 }

 - (void)newVideoSample:(CMSampleBufferRef)sampleBuffer {
   if (_videoWriter.status != AVAssetWriterStatusWriting) {
     if (_videoWriter.status == AVAssetWriterStatusFailed) {
       _eventSink(@{
         @"event" : @"error",
         @"errorDescription" : [NSString stringWithFormat:@"%@", _videoWriter.error]
       });
     }
     return;
   }
   if (_videoWriterInput.readyForMoreMediaData) {
     if (![_videoWriterInput appendSampleBuffer:sampleBuffer]) {
       _eventSink(@{
         @"event" : @"error",
         @"errorDescription" :
             [NSString stringWithFormat:@"%@", @"Unable to write to video input"]
       });
     }
   }
 }

 - (void)newAudioSample:(CMSampleBufferRef)sampleBuffer {
   if (_videoWriter.status != AVAssetWriterStatusWriting) {
     if (_videoWriter.status == AVAssetWriterStatusFailed) {
       _eventSink(@{
         @"event" : @"error",
         @"errorDescription" : [NSString stringWithFormat:@"%@", _videoWriter.error]
       });
     }
     return;
   }
   if (_audioWriterInput.readyForMoreMediaData) {
     if (![_audioWriterInput appendSampleBuffer:sampleBuffer]) {
       _eventSink(@{
         @"event" : @"error",
         @"errorDescription" :
             [NSString stringWithFormat:@"%@", @"Unable to write to audio input"]
       });
     }
   }
 }

 - (void)close {
   [_captureSession stopRunning];
   for (AVCaptureInput *input in [_captureSession inputs]) {
     [_captureSession removeInput:input];
   }
   for (AVCaptureOutput *output in [_captureSession outputs]) {
     [_captureSession removeOutput:output];
   }
 }

 - (void)dealloc {
   if (_latestPixelBuffer) {
     CFRelease(_latestPixelBuffer);
   }
 }

 - (CVPixelBufferRef)copyPixelBuffer {
   CVPixelBufferRef pixelBuffer = _latestPixelBuffer;
   while (!OSAtomicCompareAndSwapPtrBarrier(pixelBuffer, nil, (void **)&_latestPixelBuffer)) {
     pixelBuffer = _latestPixelBuffer;
   }
   return pixelBuffer;
 }

 - (FlutterError *_Nullable)onCancelWithArguments:(id _Nullable)arguments {
   _eventSink = nil;
   return nil;
 }

 - (FlutterError *_Nullable)onListenWithArguments:(id _Nullable)arguments
                                        eventSink:(nonnull FlutterEventSink)events {
   _eventSink = events;
   return nil;
 }
 - (void)startVideoRecordingAtPath:(NSString *)path result:(FlutterResult)result {
   if (!_isRecording) {
     if (![self setupWriterForPath:path]) {
       _eventSink(@{@"event" : @"error", @"errorDescription" : @"Setup Writer Failed"});
       return;
     }
     [_captureSession stopRunning];
     _isRecording = YES;
     [_captureSession startRunning];
     result(nil);
   } else {
     _eventSink(@{@"event" : @"error", @"errorDescription" : @"Video is already recording!"});
   }
 }

 - (void)stopVideoRecordingWithResult:(FlutterResult)result {
   if (_isRecording) {
     _isRecording = NO;
     if (_videoWriter.status != AVAssetWriterStatusUnknown) {
       [_videoWriter finishWritingWithCompletionHandler:^{
         if (self->_videoWriter.status == AVAssetWriterStatusCompleted) {
           result(nil);
         } else {
           self->_eventSink(@{
             @"event" : @"error",
             @"errorDescription" : @"AVAssetWriter could not finish writing!"
           });
         }
       }];
     }
   } else {
     NSError *error =
         [NSError errorWithDomain:NSCocoaErrorDomain
                             code:NSURLErrorResourceUnavailable
                         userInfo:@{NSLocalizedDescriptionKey : @"Video is not recording!"}];
     result([error flutterError]);
   }
 }

 - (BOOL)setupWriterForPath:(NSString *)path {
   NSError *error = nil;
   NSURL *outputURL;
   if (path != nil) {
     outputURL = [NSURL fileURLWithPath:path];
   } else {
     return NO;
   }
   if (!_isAudioSetup) {
     [self setUpCaptureSessionForAudio];
   }
   _videoWriter =
       [[AVAssetWriter alloc] initWithURL:outputURL fileType:AVFileTypeQuickTimeMovie error:&error];
   NSParameterAssert(_videoWriter);
   if (error) {
     _eventSink(@{@"event" : @"error", @"errorDescription" : error.description});
     return NO;
   }
   NSDictionary *videoSettings = [NSDictionary
       dictionaryWithObjectsAndKeys:AVVideoCodecH264, AVVideoCodecKey,
                                    [NSNumber numberWithInt:_previewSize.height], AVVideoWidthKey,
                                    [NSNumber numberWithInt:_previewSize.width], AVVideoHeightKey,
                                    nil];
   _videoWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo
                                                          outputSettings:videoSettings];
   NSParameterAssert(_videoWriterInput);
   _videoWriterInput.expectsMediaDataInRealTime = YES;

   // Add the audio input
   AudioChannelLayout acl;
   bzero(&acl, sizeof(acl));
   acl.mChannelLayoutTag = kAudioChannelLayoutTag_Mono;
   NSDictionary *audioOutputSettings = nil;
   // Both type of audio inputs causes output video file to be corrupted.
   audioOutputSettings = [NSDictionary
       dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:kAudioFormatMPEG4AAC], AVFormatIDKey,
                                    [NSNumber numberWithFloat:44100.0], AVSampleRateKey,
                                    [NSNumber numberWithInt:1], AVNumberOfChannelsKey,
                                    [NSData dataWithBytes:&acl length:sizeof(acl)],
                                    AVChannelLayoutKey, nil];
   _audioWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeAudio
                                                          outputSettings:audioOutputSettings];
   _audioWriterInput.expectsMediaDataInRealTime = YES;
   [_videoWriter addInput:_videoWriterInput];
   [_videoWriter addInput:_audioWriterInput];
   dispatch_queue_t queue = dispatch_queue_create("MyQueue", NULL);
   [_captureVideoOutput setSampleBufferDelegate:self queue:queue];
   [_audioOutput setSampleBufferDelegate:self queue:queue];

   return YES;
 }
 - (void)setUpCaptureSessionForAudio {
   NSError *error = nil;
   // Create a device input with the device and add it to the session.
   // Setup the audio input.
   AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
   AVCaptureDeviceInput *audioInput =
       [AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:&error];
   if (error) {
     _eventSink(@{@"event" : @"error", @"errorDescription" : error.description});
   }
   // Setup the audio output.
   _audioOutput = [[AVCaptureAudioDataOutput alloc] init];

   if ([_captureSession canAddInput:audioInput]) {
     [_captureSession addInput:audioInput];

     if ([_captureSession canAddOutput:_audioOutput]) {
       [_captureSession addOutput:_audioOutput];
       _isAudioSetup = YES;
     } else {
       _eventSink(@{
         @"event" : @"error",
         @"errorDescription" : @"Unable to add Audio input/output to session capture"
       });
       _isAudioSetup = NO;
     }
   }
 }
 @end

 @interface CameraPlugin ()
 @property(readonly, nonatomic) NSObject<FlutterTextureRegistry> *registry;
 @property(readonly, nonatomic) NSObject<FlutterBinaryMessenger> *messenger;
 @property(readonly, nonatomic) FLTCam *camera;
 @end

 @implementation CameraPlugin
 + (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar> *)registrar {
   FlutterMethodChannel *channel =
       [FlutterMethodChannel methodChannelWithName:@"plugins.flutter.io/camera"
                                   binaryMessenger:[registrar messenger]];
   CameraPlugin *instance =
       [[CameraPlugin alloc] initWithRegistry:[registrar textures] messenger:[registrar messenger]];
   [registrar addMethodCallDelegate:instance channel:channel];
 }

 - (instancetype)initWithRegistry:(NSObject<FlutterTextureRegistry> *)registry
                        messenger:(NSObject<FlutterBinaryMessenger> *)messenger {
   self = [super init];
   NSAssert(self, @"super init cannot be nil");
   _registry = registry;
   _messenger = messenger;
   return self;
 }

 - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result {
   if ([@"init" isEqualToString:call.method]) {
     if (_camera) {
       [_camera close];
     }
     result(nil);
   } else if ([@"availableCameras" isEqualToString:call.method]) {
     AVCaptureDeviceDiscoverySession *discoverySession = [AVCaptureDeviceDiscoverySession
         discoverySessionWithDeviceTypes:@[ AVCaptureDeviceTypeBuiltInWideAngleCamera ]
                               mediaType:AVMediaTypeVideo
                                position:AVCaptureDevicePositionUnspecified];
     NSArray<AVCaptureDevice *> *devices = discoverySession.devices;
     NSMutableArray<NSDictionary<NSString *, NSObject *> *> *reply =
         [[NSMutableArray alloc] initWithCapacity:devices.count];
     for (AVCaptureDevice *device in devices) {
       NSString *lensFacing;
       switch ([device position]) {
         case AVCaptureDevicePositionBack:
           lensFacing = @"back";
           break;
         case AVCaptureDevicePositionFront:
           lensFacing = @"front";
           break;
         case AVCaptureDevicePositionUnspecified:
           lensFacing = @"external";
           break;
       }
       [reply addObject:@{
         @"name" : [device uniqueID],
         @"lensFacing" : lensFacing,
       }];
     }
     result(reply);
   } else if ([@"initialize" isEqualToString:call.method]) {
     NSString *cameraName = call.arguments[@"cameraName"];
     NSString *resolutionPreset = call.arguments[@"resolutionPreset"];
     NSError *error;
     FLTCam *cam = [[FLTCam alloc] initWithCameraName:cameraName
                                     resolutionPreset:resolutionPreset
                                                error:&error];
     if (error) {
       result([error flutterError]);
     } else {
       if (_camera) {
         [_camera close];
       }
       int64_t textureId = [_registry registerTexture:cam];
       _camera = cam;
       cam.onFrameAvailable = ^{
         [_registry textureFrameAvailable:textureId];
       };
       FlutterEventChannel *eventChannel = [FlutterEventChannel
           eventChannelWithName:[NSString
                                    stringWithFormat:@"flutter.io/cameraPlugin/cameraEvents%lld",
                                                     textureId]
                binaryMessenger:_messenger];
       [eventChannel setStreamHandler:cam];
       cam.eventChannel = eventChannel;
       result(@{
         @"textureId" : @(textureId),
         @"previewWidth" : @(cam.previewSize.width),
         @"previewHeight" : @(cam.previewSize.height),
         @"captureWidth" : @(cam.captureSize.width),
         @"captureHeight" : @(cam.captureSize.height),
       });
       [cam start];
     }
   } else {
     NSDictionary *argsMap = call.arguments;
     NSUInteger textureId = ((NSNumber *)argsMap[@"textureId"]).unsignedIntegerValue;

     if ([@"takePicture" isEqualToString:call.method]) {
       [_camera captureToFile:call.arguments[@"path"] result:result];
     } else if ([@"dispose" isEqualToString:call.method]) {
       [_registry unregisterTexture:textureId];
       [_camera close];
       result(nil);
     } else if ([@"startVideoRecording" isEqualToString:call.method]) {
       [_camera startVideoRecordingAtPath:call.arguments[@"filePath"] result:result];
     } else if ([@"stopVideoRecording" isEqualToString:call.method]) {
       [_camera stopVideoRecordingWithResult:result];
     } else {
       result(FlutterMethodNotImplemented);
     }
   }
 }

 @end
	#import "CameraPlugin.h"
	#import <AVFoundation/AVFoundation.h>
	#import <libkern/OSAtomic.h>

	@interface NSError (FlutterError)
	@property(readonly, nonatomic) FlutterError *flutterError;
	@end

	@implementation NSError (FlutterError)
	- (FlutterError *)flutterError {
	return [FlutterError errorWithCode:[NSString stringWithFormat:@"Error %d", (int)self.code]
	message:self.domain
	details:self.localizedDescription];
	}
	@end

	@interface FLTSavePhotoDelegate : NSObject<AVCapturePhotoCaptureDelegate>
	@property(readonly, nonatomic) NSString *path;
	@property(readonly, nonatomic) FlutterResult result;

	- initWithPath:(NSString *)filename result:(FlutterResult)result;
	@end

	@implementation FLTSavePhotoDelegate {
	/// Used to keep the delegate alive until didFinishProcessingPhotoSampleBuffer.
	FLTSavePhotoDelegate *selfReference;
	}

	- initWithPath:(NSString *)path result:(FlutterResult)result {
	self = [super init];
	NSAssert(self, @"super init cannot be nil");
	_path = path;
	_result = result;
	selfReference = self;
	return self;
	}

	- (void)captureOutput:(AVCapturePhotoOutput *)output
	didFinishProcessingPhotoSampleBuffer:(CMSampleBufferRef)photoSampleBuffer
	previewPhotoSampleBuffer:(CMSampleBufferRef)previewPhotoSampleBuffer
	resolvedSettings:(AVCaptureResolvedPhotoSettings *)resolvedSettings
	bracketSettings:(AVCaptureBracketedStillImageSettings *)bracketSettings
	error:(NSError *)error {
	selfReference = nil;
	if (error) {
	_result([error flutterError]);
	return;
	}
	NSData *data = [AVCapturePhotoOutput
	JPEGPhotoDataRepresentationForJPEGSampleBuffer:photoSampleBuffer
	previewPhotoSampleBuffer:previewPhotoSampleBuffer];
	// TODO(sigurdm): Consider writing file asynchronously.
	bool success = [data writeToFile:_path atomically:YES];
	if (!success) {
	_result([FlutterError errorWithCode:@"IOError" message:@"Unable to write file" details:nil]);
	return;
	}
	_result(nil);
	}
	@end

	@interface FLTCam : NSObject<FlutterTexture, AVCaptureVideoDataOutputSampleBufferDelegate,
	AVCaptureAudioDataOutputSampleBufferDelegate, FlutterStreamHandler>
	@property(readonly, nonatomic) int64_t textureId;
	@property(nonatomic, copy) void (^onFrameAvailable)();
	@property(nonatomic) FlutterEventChannel *eventChannel;
	@property(nonatomic) FlutterEventSink eventSink;
	@property(readonly, nonatomic) AVCaptureSession *captureSession;
	@property(readonly, nonatomic) AVCaptureDevice *captureDevice;
	@property(readonly, nonatomic) AVCapturePhotoOutput *capturePhotoOutput;
	@property(readonly, nonatomic) AVCaptureVideoDataOutput *captureVideoOutput;
	@property(readonly, nonatomic) AVCaptureInput *captureVideoInput;
	@property(readonly) CVPixelBufferRef volatile latestPixelBuffer;
	@property(readonly, nonatomic) CGSize previewSize;
	@property(readonly, nonatomic) CGSize captureSize;
	@property(strong, nonatomic) AVAssetWriter *videoWriter;
	@property(strong, nonatomic) AVAssetWriterInput *videoWriterInput;
	@property(strong, nonatomic) AVAssetWriterInput *audioWriterInput;
	@property(strong, nonatomic) AVAssetWriterInputPixelBufferAdaptor *assetWriterPixelBufferAdaptor;
	@property(strong, nonatomic) AVCaptureVideoDataOutput *videoOutput;
	@property(strong, nonatomic) AVCaptureAudioDataOutput *audioOutput;
	@property(assign, nonatomic) BOOL isRecording;
	@property(assign, nonatomic) BOOL isAudioSetup;
	- (instancetype)initWithCameraName:(NSString *)cameraName
	resolutionPreset:(NSString *)resolutionPreset
	error:(NSError **)error;
	- (void)start;
	- (void)stop;
	- (void)startVideoRecordingAtPath:(NSString *)path result:(FlutterResult)result;
	- (void)stopVideoRecordingWithResult:(FlutterResult)result;
	- (void)captureToFile:(NSString *)filename result:(FlutterResult)result;
	@end

	@implementation FLTCam
	- (instancetype)initWithCameraName:(NSString *)cameraName
	resolutionPreset:(NSString *)resolutionPreset
	error:(NSError **)error {
	self = [super init];
	NSAssert(self, @"super init cannot be nil");
	_captureSession = [[AVCaptureSession alloc] init];
	AVCaptureSessionPreset preset;
	if ([resolutionPreset isEqualToString:@"high"]) {
	preset = AVCaptureSessionPresetHigh;
	} else if ([resolutionPreset isEqualToString:@"medium"]) {
	preset = AVCaptureSessionPresetMedium;
	} else {
	NSAssert([resolutionPreset isEqualToString:@"low"], @"Unknown resolution preset %@",
	resolutionPreset);
	preset = AVCaptureSessionPresetLow;
	}
	_captureSession.sessionPreset = preset;
	_captureDevice = [AVCaptureDevice deviceWithUniqueID:cameraName];
	NSError *localError = nil;
	_captureVideoInput =
	[AVCaptureDeviceInput deviceInputWithDevice:_captureDevice error:&localError];
	if (localError) {
	*error = localError;
	return nil;
	}
	CMVideoDimensions dimensions =
	CMVideoFormatDescriptionGetDimensions([[_captureDevice activeFormat] formatDescription]);
	_previewSize = CGSizeMake(dimensions.width, dimensions.height);

	_captureVideoOutput = [AVCaptureVideoDataOutput new];
	_captureVideoOutput.videoSettings =
	@{(NSString *)kCVPixelBufferPixelFormatTypeKey : @(kCVPixelFormatType_32BGRA) };
	[_captureVideoOutput setAlwaysDiscardsLateVideoFrames:YES];
	[_captureVideoOutput setSampleBufferDelegate:self queue:dispatch_get_main_queue()];

	AVCaptureConnection *connection =
	[AVCaptureConnection connectionWithInputPorts:_captureVideoInput.ports
	output:_captureVideoOutput];
	if ([_captureDevice position] == AVCaptureDevicePositionFront) {
	connection.videoMirrored = YES;
	}
	connection.videoOrientation = AVCaptureVideoOrientationPortrait;
	[_captureSession addInputWithNoConnections:_captureVideoInput];
	[_captureSession addOutputWithNoConnections:_captureVideoOutput];
	[_captureSession addConnection:connection];
	_capturePhotoOutput = [AVCapturePhotoOutput new];
	[_captureSession addOutput:_capturePhotoOutput];
	return self;
	}

	- (void)start {
	[_captureSession startRunning];
	}

	- (void)stop {
	[_captureSession stopRunning];
	}

	- (void)captureToFile:(NSString *)path result:(FlutterResult)result {
	AVCapturePhotoSettings *settings = [AVCapturePhotoSettings photoSettings];
	[_capturePhotoOutput
	capturePhotoWithSettings:settings
	delegate:[[FLTSavePhotoDelegate alloc] initWithPath:path result:result]];
	}

	- (void)captureOutput:(AVCaptureOutput *)output
	didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
	fromConnection:(AVCaptureConnection *)connection {
	if (output == _captureVideoOutput) {
	CVPixelBufferRef newBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
	CFRetain(newBuffer);
	CVPixelBufferRef old = _latestPixelBuffer;
	while (!OSAtomicCompareAndSwapPtrBarrier(old, newBuffer, (void **)&_latestPixelBuffer)) {
	old = _latestPixelBuffer;
	}
	if (old != nil) {
	CFRelease(old);
	}
	if (_onFrameAvailable) {
	_onFrameAvailable();
	}
	}
	if (!CMSampleBufferDataIsReady(sampleBuffer)) {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" : @"sample buffer is not ready. Skipping sample"
	});
	return;
	}
	if (_isRecording) {
	if (_videoWriter.status == AVAssetWriterStatusFailed) {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" : [NSString stringWithFormat:@"%@", _videoWriter.error]
	});
	return;
	}
	CMTime lastSampleTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
	if (_videoWriter.status != AVAssetWriterStatusWriting) {
	[_videoWriter startWriting];
	[_videoWriter startSessionAtSourceTime:lastSampleTime];
	}
	if (output == _captureVideoOutput) {
	[self newVideoSample:sampleBuffer];
	} else {
	[self newAudioSample:sampleBuffer];
	}
	}
	}

	- (void)newVideoSample:(CMSampleBufferRef)sampleBuffer {
	if (_videoWriter.status != AVAssetWriterStatusWriting) {
	if (_videoWriter.status == AVAssetWriterStatusFailed) {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" : [NSString stringWithFormat:@"%@", _videoWriter.error]
	});
	}
	return;
	}
	if (_videoWriterInput.readyForMoreMediaData) {
	if (![_videoWriterInput appendSampleBuffer:sampleBuffer]) {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" :
	[NSString stringWithFormat:@"%@", @"Unable to write to video input"]
	});
	}
	}
	}

	- (void)newAudioSample:(CMSampleBufferRef)sampleBuffer {
	if (_videoWriter.status != AVAssetWriterStatusWriting) {
	if (_videoWriter.status == AVAssetWriterStatusFailed) {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" : [NSString stringWithFormat:@"%@", _videoWriter.error]
	});
	}
	return;
	}
	if (_audioWriterInput.readyForMoreMediaData) {
	if (![_audioWriterInput appendSampleBuffer:sampleBuffer]) {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" :
	[NSString stringWithFormat:@"%@", @"Unable to write to audio input"]
	});
	}
	}
	}

	- (void)close {
	[_captureSession stopRunning];
	for (AVCaptureInput *input in [_captureSession inputs]) {
	[_captureSession removeInput:input];
	}
	for (AVCaptureOutput *output in [_captureSession outputs]) {
	[_captureSession removeOutput:output];
	}
	}

	- (void)dealloc {
	if (_latestPixelBuffer) {
	CFRelease(_latestPixelBuffer);
	}
	}

	- (CVPixelBufferRef)copyPixelBuffer {
	CVPixelBufferRef pixelBuffer = _latestPixelBuffer;
	while (!OSAtomicCompareAndSwapPtrBarrier(pixelBuffer, nil, (void **)&_latestPixelBuffer)) {
	pixelBuffer = _latestPixelBuffer;
	}
	return pixelBuffer;
	}

	- (FlutterError *_Nullable)onCancelWithArguments:(id _Nullable)arguments {
	_eventSink = nil;
	return nil;
	}

	- (FlutterError *_Nullable)onListenWithArguments:(id _Nullable)arguments
	eventSink:(nonnull FlutterEventSink)events {
	_eventSink = events;
	return nil;
	}
	- (void)startVideoRecordingAtPath:(NSString *)path result:(FlutterResult)result {
	if (!_isRecording) {
	if (![self setupWriterForPath:path]) {
	_eventSink(@{@"event" : @"error", @"errorDescription" : @"Setup Writer Failed"});
	return;
	}
	[_captureSession stopRunning];
	_isRecording = YES;
	[_captureSession startRunning];
	result(nil);
	} else {
	_eventSink(@{@"event" : @"error", @"errorDescription" : @"Video is already recording!"});
	}
	}

	- (void)stopVideoRecordingWithResult:(FlutterResult)result {
	if (_isRecording) {
	_isRecording = NO;
	if (_videoWriter.status != AVAssetWriterStatusUnknown) {
	[_videoWriter finishWritingWithCompletionHandler:^{
	if (self->_videoWriter.status == AVAssetWriterStatusCompleted) {
	result(nil);
	} else {
	self->_eventSink(@{
	@"event" : @"error",
	@"errorDescription" : @"AVAssetWriter could not finish writing!"
	});
	}
	}];
	}
	} else {
	NSError *error =
	[NSError errorWithDomain:NSCocoaErrorDomain
	code:NSURLErrorResourceUnavailable
	userInfo:@{NSLocalizedDescriptionKey : @"Video is not recording!"}];
	result([error flutterError]);
	}
	}

	- (BOOL)setupWriterForPath:(NSString *)path {
	NSError *error = nil;
	NSURL *outputURL;
	if (path != nil) {
	outputURL = [NSURL fileURLWithPath:path];
	} else {
	return NO;
	}
	if (!_isAudioSetup) {
	[self setUpCaptureSessionForAudio];
	}
	_videoWriter =
	[[AVAssetWriter alloc] initWithURL:outputURL fileType:AVFileTypeQuickTimeMovie error:&error];
	NSParameterAssert(_videoWriter);
	if (error) {
	_eventSink(@{@"event" : @"error", @"errorDescription" : error.description});
	return NO;
	}
	NSDictionary *videoSettings = [NSDictionary
	dictionaryWithObjectsAndKeys:AVVideoCodecH264, AVVideoCodecKey,
	[NSNumber numberWithInt:_previewSize.height], AVVideoWidthKey,
	[NSNumber numberWithInt:_previewSize.width], AVVideoHeightKey,
	nil];
	_videoWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo
	outputSettings:videoSettings];
	NSParameterAssert(_videoWriterInput);
	_videoWriterInput.expectsMediaDataInRealTime = YES;

	// Add the audio input
	AudioChannelLayout acl;
	bzero(&acl, sizeof(acl));
	acl.mChannelLayoutTag = kAudioChannelLayoutTag_Mono;
	NSDictionary *audioOutputSettings = nil;
	// Both type of audio inputs causes output video file to be corrupted.
	audioOutputSettings = [NSDictionary
	dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:kAudioFormatMPEG4AAC], AVFormatIDKey,
	[NSNumber numberWithFloat:44100.0], AVSampleRateKey,
	[NSNumber numberWithInt:1], AVNumberOfChannelsKey,
	[NSData dataWithBytes:&acl length:sizeof(acl)],
	AVChannelLayoutKey, nil];
	_audioWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeAudio
	outputSettings:audioOutputSettings];
	_audioWriterInput.expectsMediaDataInRealTime = YES;
	[_videoWriter addInput:_videoWriterInput];
	[_videoWriter addInput:_audioWriterInput];
	dispatch_queue_t queue = dispatch_queue_create("MyQueue", NULL);
	[_captureVideoOutput setSampleBufferDelegate:self queue:queue];
	[_audioOutput setSampleBufferDelegate:self queue:queue];

	return YES;
	}
	- (void)setUpCaptureSessionForAudio {
	NSError *error = nil;
	// Create a device input with the device and add it to the session.
	// Setup the audio input.
	AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
	AVCaptureDeviceInput *audioInput =
	[AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:&error];
	if (error) {
	_eventSink(@{@"event" : @"error", @"errorDescription" : error.description});
	}
	// Setup the audio output.
	_audioOutput = [[AVCaptureAudioDataOutput alloc] init];

	if ([_captureSession canAddInput:audioInput]) {
	[_captureSession addInput:audioInput];

	if ([_captureSession canAddOutput:_audioOutput]) {
	[_captureSession addOutput:_audioOutput];
	_isAudioSetup = YES;
	} else {
	_eventSink(@{
	@"event" : @"error",
	@"errorDescription" : @"Unable to add Audio input/output to session capture"
	});
	_isAudioSetup = NO;
	}
	}
	}
	@end

	@interface CameraPlugin ()
	@property(readonly, nonatomic) NSObject<FlutterTextureRegistry> *registry;
	@property(readonly, nonatomic) NSObject<FlutterBinaryMessenger> *messenger;
	@property(readonly, nonatomic) FLTCam *camera;
	@end

	@implementation CameraPlugin
	+ (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar> *)registrar {
	FlutterMethodChannel *channel =
	[FlutterMethodChannel methodChannelWithName:@"plugins.flutter.io/camera"
	binaryMessenger:[registrar messenger]];
	CameraPlugin *instance =
	[[CameraPlugin alloc] initWithRegistry:[registrar textures] messenger:[registrar messenger]];
	[registrar addMethodCallDelegate:instance channel:channel];
	}

	- (instancetype)initWithRegistry:(NSObject<FlutterTextureRegistry> *)registry
	messenger:(NSObject<FlutterBinaryMessenger> *)messenger {
	self = [super init];
	NSAssert(self, @"super init cannot be nil");
	_registry = registry;
	_messenger = messenger;
	return self;
	}

	- (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result {
	if ([@"init" isEqualToString:call.method]) {
	if (_camera) {
	[_camera close];
	}
	result(nil);
	} else if ([@"availableCameras" isEqualToString:call.method]) {
	AVCaptureDeviceDiscoverySession *discoverySession = [AVCaptureDeviceDiscoverySession
	discoverySessionWithDeviceTypes:@[ AVCaptureDeviceTypeBuiltInWideAngleCamera ]
	mediaType:AVMediaTypeVideo
	position:AVCaptureDevicePositionUnspecified];
	NSArray<AVCaptureDevice > devices = discoverySession.devices;
	NSMutableArray<NSDictionary<NSString , NSObject > > reply =
	[[NSMutableArray alloc] initWithCapacity:devices.count];
	for (AVCaptureDevice *device in devices) {
	NSString *lensFacing;
	switch ([device position]) {
	case AVCaptureDevicePositionBack:
	lensFacing = @"back";
	break;
	case AVCaptureDevicePositionFront:
	lensFacing = @"front";
	break;
	case AVCaptureDevicePositionUnspecified:
	lensFacing = @"external";
	break;
	}
	[reply addObject:@{
	@"name" : [device uniqueID],
	@"lensFacing" : lensFacing,
	}];
	}
	result(reply);
	} else if ([@"initialize" isEqualToString:call.method]) {
	NSString *cameraName = call.arguments[@"cameraName"];
	NSString *resolutionPreset = call.arguments[@"resolutionPreset"];
	NSError *error;
	FLTCam *cam = [[FLTCam alloc] initWithCameraName:cameraName
	resolutionPreset:resolutionPreset
	error:&error];
	if (error) {
	result([error flutterError]);
	} else {
	if (_camera) {
	[_camera close];
	}
	int64_t textureId = [_registry registerTexture:cam];
	_camera = cam;
	cam.onFrameAvailable = ^{
	[_registry textureFrameAvailable:textureId];
	};
	FlutterEventChannel *eventChannel = [FlutterEventChannel
	eventChannelWithName:[NSString
	stringWithFormat:@"flutter.io/cameraPlugin/cameraEvents%lld",
	textureId]
	binaryMessenger:_messenger];
	[eventChannel setStreamHandler:cam];
	cam.eventChannel = eventChannel;
	result(@{
	@"textureId" : @(textureId),
	@"previewWidth" : @(cam.previewSize.width),
	@"previewHeight" : @(cam.previewSize.height),
	@"captureWidth" : @(cam.captureSize.width),
	@"captureHeight" : @(cam.captureSize.height),
	});
	[cam start];
	}
	} else {
	NSDictionary *argsMap = call.arguments;
	NSUInteger textureId = ((NSNumber *)argsMap[@"textureId"]).unsignedIntegerValue;

	if ([@"takePicture" isEqualToString:call.method]) {
	[_camera captureToFile:call.arguments[@"path"] result:result];
	} else if ([@"dispose" isEqualToString:call.method]) {
	[_registry unregisterTexture:textureId];
	[_camera close];
	result(nil);
	} else if ([@"startVideoRecording" isEqualToString:call.method]) {
	[_camera startVideoRecordingAtPath:call.arguments[@"filePath"] result:result];
	} else if ([@"stopVideoRecording" isEqualToString:call.method]) {
	[_camera stopVideoRecordingWithResult:result];
	} else {
	result(FlutterMethodNotImplemented);
	}
	}
	}

	@end