gistfile1.m

#import "CaptureSessionManager.h"


@implementation CaptureSessionManager

@synthesize captureSession;
@synthesize previewLayer;
@synthesize stillImage, stillImageOutput;

#pragma mark Capture Session Configuration

- (id)init {
	if ((self = [super init])) {
		self.captureSession = [[[AVCaptureSession alloc] init] autorelease];

        if ([self.captureSession canSetSessionPreset:AVCaptureSessionPreset640x480])
            self.captureSession.sessionPreset = AVCaptureSessionPreset640x480;
    }
	return self;
}

- (void)addVideoInput 
{
	AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];	
	if (videoDevice) {
		NSError *error;
		AVCaptureDeviceInput *videoIn = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&error];
		if (!error && [self.captureSession canAddInput:videoIn])
            [self.captureSession addInput:videoIn];
	}
	else
		NSLog(@"ERROR: Couldn't create video capture device");
}

- (void)addVideoPreviewLayer 
{
	self.previewLayer = [[[AVCaptureVideoPreviewLayer alloc] initWithSession:self.captureSession] autorelease];
	[self.previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
    
}

- (void)addStillImageOutput
{
    self.stillImageOutput = [[[AVCaptureStillImageOutput alloc] init] autorelease];
    NSDictionary *outputSettings = [[[NSDictionary alloc] initWithObjectsAndKeys:AVVideoCodecJPEG,AVVideoCodecKey,nil] autorelease];
    [self.stillImageOutput setOutputSettings:outputSettings];
    
    if ([self.captureSession canAddOutput:self.stillImageOutput])
        [self.captureSession addOutput:self.stillImageOutput];
    else
        NSLog(@"ERROR: Could not create video output");
}

- (AVCaptureConnection*)getConnection
{
	for (AVCaptureConnection *connection in self.stillImageOutput.connections) 
		for (AVCaptureInputPort *port in [connection inputPorts]) 
			if ([[port mediaType] isEqual:AVMediaTypeVideo]) 
                return connection;
    NSLog(@"ERROR: Could not find connection");
    return nil;
}

- (void)captureStillImage
{
 	[self.stillImageOutput captureStillImageAsynchronouslyFromConnection:[self getConnection]
                                                       completionHandler:^(CMSampleBufferRef imageSampleBuffer, NSError *error) 
                                                       {
                                                             CFDictionaryRef exifAttachments = CMGetAttachment(imageSampleBuffer, kCGImagePropertyExifDictionary, NULL);
                                                             if (exifAttachments)
                                                                 NSLog(@"EXIF: %@", exifAttachments);
                                                             else
                                                                 NSLog(@"no EXIF");
                                                           
                                                             NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageSampleBuffer];
                                                             UIImage *image = [[UIImage alloc] initWithData:imageData];
                                                             self.stillImage = image;
                                                             [image release];
                                                           
                                                             [[NSNotificationCenter defaultCenter] postNotificationName:kImageCapturedSuccessfully object:nil];
                                                         }];
}

- (void)dealloc {
    
	[self.captureSession stopRunning];
    
	[previewLayer release];
	[captureSession release];
    
	[super dealloc];
}

@end