iOS自定义相机Demo

//  Created by David_Tian on 14-9-24.
//  Copyright (c) 2014年 All rights reserved.
//  未做适配,有兴趣的童鞋可以扩展

#import "cameraViewController.h"
#import <AVFoundation/AVFoundation.h>
#import <ImageIO/ImageIO.h>
#import <QuartzCore/QuartzCore.h>

typedef enum{
    isFrontCamera = 0,
    isBackCamera
} cameraType;

typedef enum{
    AutoFlash = 0,
    CloseFlash,
    OpenFlash
} flashModel;

@interface cameraViewController ()
< AVCaptureAudioDataOutputSampleBufferDelegate, UIImagePickerControllerDelegate >
{
    UIImage *_photo;
    BOOL _isFontCamera;
}

@property (strong, nonatomic) AVCaptureSession           *session;       // 捕获会话
@property (nonatomic, strong) AVCaptureStillImageOutput  *captureOutput; // 输出设备
@property (nonatomic, strong) AVCaptureVideoPreviewLayer *previewLayer;  // 取景器 

@end

@implementation cameraViewController

- (AVCaptureSession *)session
{
    if (_session == nil) {
        _session = [[AVCaptureSession alloc] init];
    }
    return _session;
}
- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor grayColor];
    UIButton *btnCam = [[UIButton alloc]initWithFrame:CGRectMake(20, 44, 80, 30)];
    [btnCam setTitle:@"拍照" forState:UIControlStateNormal];
    [btnCam setTitle:@"重照" forState:UIControlStateSelected];//重拍没做
    [btnCam setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btnCam addTarget:self action:@selector(capture) forControlEvents:UIControlEventTouchUpInside];
    [btnCam setBackgroundColor:[UIColor whiteColor]];
    [self.view addSubview:btnCam];

    UIButton *btnSelectCam = [[UIButton alloc]initWithFrame:CGRectMake(110, 44, 80, 30)];
    [btnSelectCam setTitle:@"后置相机" forState:UIControlStateNormal];
    [btnSelectCam setTitle:@"前置相机" forState:UIControlStateSelected];
    [btnSelectCam setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btnSelectCam addTarget:self action:@selector(switchCamera:) forControlEvents:UIControlEventTouchUpInside];
    [btnSelectCam setBackgroundColor:[UIColor whiteColor]];
    [self.view addSubview:btnSelectCam];  

    UIButton *btnFlash = [[UIButton alloc]initWithFrame:CGRectMake(200, 44, 80, 30)];
    [btnFlash setTitle:@"闪光灯" forState:UIControlStateNormal];
    [btnFlash setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btnFlash addTarget:self action:@selector(switchFlashMode:) forControlEvents:UIControlEventTouchUpInside];
    [btnFlash setBackgroundColor:[UIColor whiteColor]];
    [self.view addSubview:btnFlash];

    [self switchCamera:nil];
}
#pragma mark - action
// 拍照
- (void)capture
{
    if (![self.session isRunning]) {
        [self getPhoto];
    }else{
        [_session stopRunning];
    }
}
// 切换摄像头
- (void)switchCamera:(UIButton *)sender
{
    [self.session stopRunning];
    [_previewLayer removeFromSuperlayer];
    sender.selected = !sender.selected;
    _isFontCamera = !_isFontCamera;
    [self setupCamera];
}
// 获取图片
- (void)getPhoto
{
    AVCaptureConnection *videoConnection = nil;
    for (AVCaptureConnection *connection in _captureOutput.connections) {
        for (AVCaptureInputPort *port in [connection inputPorts]) {
            if ([[port mediaType] isEqual:AVMediaTypeVideo] ) {
                videoConnection = connection;
                break;
            }
        }
        if (videoConnection) {
            break;
        }
    }
    [_captureOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:^(CMSampleBufferRef imageSampleBuffer, NSError *error)
    {
        CFDictionaryRef exifAttachments = CMGetAttachment(imageSampleBuffer, kCGImagePropertyExifDictionary, nil);
        if (exifAttachments) {
            // Do something with the attachments.
        }
        // 获取图片数据
        NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageSampleBuffer];
        UIImage *t_image = [[UIImage alloc] initWithData:imageData];
        _photo = [[UIImage alloc]initWithCGImage:t_image.CGImage scale:1.5 orientation:UIImageOrientationRight];
        UIImageView *imageView = [[UIImageView alloc]initWithFrame:_previewLayer.frame];
        [_previewLayer removeFromSuperlayer];
        imageView.image = _photo;
        imageView.contentMode = UIViewContentModeScaleAspectFill;
        imageView.clipsToBounds = YES;
        [self.view addSubview:imageView];
    }];
}

// 切换闪光灯模式
- (void)switchFlashMode:(UIButton*)sender {
    Class captureDeviceClass = NSClassFromString(@"AVCaptureDevice");
    if (!captureDeviceClass) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示信息" message:@"您的设备没有拍照功能" delegate:nil cancelButtonTitle:NSLocalizedString(@"Sure", nil) otherButtonTitles: nil];
        [alert show];
        return;
    }
    NSString *imgName = @"";
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    [device lockForConfiguration:nil];
    if ([device hasFlash]) {
        if (device.flashMode == AVCaptureFlashModeOff) {
            device.flashMode = AVCaptureFlashModeOn;
            imgName = @"";
        } else if (device.flashMode == AVCaptureFlashModeOn) {
            device.flashMode = AVCaptureFlashModeAuto;
            imgName = @"";
        } else if (device.flashMode == AVCaptureFlashModeAuto) {
            device.flashMode = AVCaptureFlashModeOff;
            imgName = @"";
        }
        if (sender) {
            [sender setImage:[UIImage imageNamed:imgName] forState:UIControlStateNormal];
        }
    } else {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示信息" message:@"您的设备没有闪光灯功能" delegate:nil cancelButtonTitle:@"ok" otherButtonTitles: nil];
        [alert show];
    }
    [device unlockForConfiguration];
}

// 初始化相机

- (void)setupCamera
{
    AVCaptureDevice *captureDevice = [self getVideoInputCamera:(_isFontCamera ? isFrontCamera : isBackCamera)];
    AVCaptureDeviceInput *deviceInput = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:nil];
    if ([self.session canAddInput:deviceInput]){
        [_session addInput:deviceInput];
    }

    // 预览视图(取景器)
    _previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.session];
    [_previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];

    CALayer *preLayer = [[self view] layer];
    [preLayer setMasksToBounds:YES];
    [_previewLayer setFrame:CGRectMake(10, 100, 300, 300)];
    [preLayer insertSublayer:_previewLayer atIndex:0];
    [_session startRunning];

    // 创建一个输出设备,并将它添加到会话
    _captureOutput = [[AVCaptureStillImageOutput alloc] init];
    NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys:AVVideoCodecJPEG,AVVideoCodecKey,nil];
    _captureOutput.outputSettings = outputSettings;
    [_session addOutput:_captureOutput];
}

#pragma mark VideoCapture
- (AVCaptureDevice *)getVideoInputCamera:(cameraType )cameraType
{
    //获取(后置/前置)摄像头设备
    NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    for (AVCaptureDevice *device in cameras){
        switch (cameraType) {
            case isFrontCamera:
                if (device.position == AVCaptureDevicePositionFront)
                    return device;
                break;
            case isBackCamera:
                if (device.position == AVCaptureDevicePositionBack)
                    return device;
                break;
            default:
                break;
        }
    }
    return [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
}

@end