AVFoundation Video

videoViewController.h

//
//  DetailViewController.h
//  Sync Camera
//
//  Created by kuninorif on 2014/05/22.
//  Copyright (c) 2014年 kuninori. All rights reserved.
//

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
#import <Accelerate/Accelerate.h>

@interface DetailViewController : UIViewController

@property (strong, nonatomic) id detailItem;

@property (nonatomic) AVCaptureSession *session;

@property (nonatomic) AVCaptureStillImageOutput *imageOutput;

@property (weak, nonatomic) IBOutlet UIView *previewView;
@property (weak, nonatomic) IBOutlet UILabel *detailDescriptionLabel;


@end

videoViewController.m

//
//  DetailViewController.m
//  Sync Camera
//
//  Created by kuninorif on 2014/05/22.
//  Copyright (c) 2014年 kuninori. All rights reserved.
//

#import "DetailViewController.h"

@interface DetailViewController () <AVCaptureVideoDataOutputSampleBufferDelegate>
- (void)configureView;
@end

@implementation DetailViewController

#pragma mark - Managing the detail item

- (void)setDetailItem:(id)newDetailItem
{
    if (_detailItem != newDetailItem) {
        _detailItem = newDetailItem;
        
        // Update the view.
        [self configureView];
    }
}

- (void)configureView
{
}

- (void)viewDidLoad
{
	self.session = [[AVCaptureSession alloc] init];

	if( [self.session canSetSessionPreset:AVCaptureSessionPresetHigh] ){
		self.session.sessionPreset = AVCaptureSessionPresetHigh;
	}
	
	
	// シュミレーターでは動かない
	NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
	AVCaptureDevice *targetdevice;
	for(AVCaptureDevice *device in devices){
		if( device.position == AVCaptureDevicePositionBack){
			targetdevice = device;
		}
	}
	
	if( targetdevice == nil ){
		NSLog(@"not foud device.");
		return;
	}
	NSError *err;
	AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:targetdevice error:&err];
	if( err != nil ){
		NSLog(@"error: %@", err);
	}
	
	if( [self.session canAddInput:input] ){
		[self.session addInput:input];
	} else {
		NSLog(@"not support");
	}
	AVCaptureVideoDataOutput *output = [[AVCaptureVideoDataOutput alloc] init];
	[output setAlwaysDiscardsLateVideoFrames:YES];
	[output setVideoSettings:@{ (NSString *)kCVPixelBufferPixelFormatTypeKey: @(kCVPixelFormatType_32BGRA) }];
	[output setSampleBufferDelegate:self queue:dispatch_get_main_queue()];
	[self.session addOutput:output];

	[self.session startRunning];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


// video buffer

-(void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
	CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
	CVPixelBufferLockBaseAddress(imageBuffer, 0);
	
  uint8_t *base = CVPixelBufferGetBaseAddress(imageBuffer);
	size_t width = CVPixelBufferGetWidth(imageBuffer);
	size_t height = CVPixelBufferGetHeight(imageBuffer);
	size_t bytes = CVPixelBufferGetBytesPerRow(imageBuffer);

    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef cgContext = CGBitmapContextCreate(base, width, height, 8,
                                                   bytes, colorSpace,
                                                   kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
    // image
    CGImageRef cgImage = CGBitmapContextCreateImage(cgContext);
    UIImage *image = [UIImage imageWithCGImage:cgImage scale:1.0 orientation:UIImageOrientationRight];
    
    CGImageRelease(cgImage);
    CGContextRelease(cgContext);
    
    // unlock
    CVPixelBufferUnlockBaseAddress(imageBuffer, false);
    self.previewView.image = image;
}

@end