iPhone摄像头设备获取

 

转载自   http://blog.csdn.net/linzhiji/article/details/6730693

目的：打开、关闭前置摄像头，绘制图像，并获取摄像头的二进制数据。需要的库AVFoundation.framework 、CoreVideo.framework 、CoreMedia.framework 、QuartzCore.framework该摄像头捕抓必须编译真机的版本，模拟器下编译不了。

函数说明

- (void)createControl{// UI界面控件的创建}

- (AVCaptureDevice *)getFrontCamera;获取前置摄像头设备

- (void)startVideoCapture;打开摄像头并开始捕捉图像其中代码：

AVCaptureVideoPreviewLayer* previewLayer = [AVCaptureVideoPreviewLayer layerWithSession: self->avCaptureSession];

previewLayer.frame = localView.bounds;

previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;

[self->localView.layer addSublayer: previewLayer]; 

为把图片画到UIView里面

- (void)stopVideoCapture:(id)arg；关闭摄像头，停止捕抓图像其中代码：

for(UIView*viewinself->localView.subviews) {[viewremoveFromSuperview];}

为移除摄像头图像的View详情见代码，代码拷过去可以直接使用     

 

代码：头文件：

//  
//  AVCallController.h  
//  Pxlinstall  
//  
//  Created by Lin Charlie C. on 11-3-24.  
//  Copyright 2011  xxxx. All rights reserved.  
//  
      
#import <UIKit/UIKit.h>  
#import <AVFoundation/AVFoundation.h>  
      
@interface AVCallController : UIViewController <AVCaptureVideoDataOutputSampleBufferDelegate>  
{  
    //UI  
    UILabel*labelState;  
    UIButton*btnStartVideo;  
    UIView*localView;  
      
    AVCaptureSession* avCaptureSession;  
    AVCaptureDevice *avCaptureDevice;  
    BOOLfirstFrame; //是否为第一帧  
    intproducerFps;  
      
      
}
  
 @property (nonatomic, retain) AVCaptureSession *avCaptureSession;  
 @property (nonatomic, retain) UILabel *labelState;  
      
      
- (void)createControl;  
- (AVCaptureDevice *)getFrontCamera;  
- (void)startVideoCapture;  
- (void)stopVideoCapture:(id)arg;  

@end  

实现文件：

        //  AVCallController.m  
        //  Pxlinstall  
        //  
        //  Created by Lin Charlie C. on 11-3-24.  
        //  Copyright 2011  高鸿移通. All rights reserved.  
        //  
          
          
        #import "AVCallController.h"  
          
          
          
          
        @implementation AVCallController  
          
          
        @synthesize avCaptureSession;  
        @synthesize labelState;  
          
          
        // The designated initializer.  Override if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad.  
        /*  
        - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {  
            self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];  
            if (self) {  
                // Custom initialization.  
            }  
            return self;  
        }  
        */  
        -(id)init  
        {  
        if(self= [superinit])  
        {  
        firstFrame= YES;  
        producerFps= 50;  
        }  
        returnself;  
        }  
          
          
        // Implement loadView to create a view hierarchy programmatically, without using a nib.  
        - (void)loadView {  
        [superloadView];  
        [selfcreateControl];  
        }  
          
          
          
          
        /*  
        // Implement viewDidLoad to do additional setup after loading the view, typically from a nib.  
        - (void)viewDidLoad {  
            [super viewDidLoad];  
        }  
        */  
          
          
        /*  
        // Override to allow orientations other than the default portrait orientation.  
        - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {  
            // Return YES for supported orientations.  
            return (interfaceOrientation == UIInterfaceOrientationPortrait);  
        }  
        */  
          
          
        - (void)didReceiveMemoryWarning {  
        // Releases the view if it doesn't have a superview.  
        [superdidReceiveMemoryWarning];  
          
        // Release any cached data, images, etc. that aren't in use.  
        }  
          
          
        - (void)viewDidUnload {  
        [superviewDidUnload];  
        // Release any retained subviews of the main view.  
        // e.g. self.myOutlet = nil;  
        }  
          
          
          
          
        - (void)dealloc {  
            [super dealloc];  
        }  
          
          
        #pragma mark -  
        #pragma mark createControl  
        - (void)createControl  
        {  
        //UI展示  
        self.view.backgroundColor= [UIColorgrayColor];  
        labelState= [[UILabelalloc] initWithFrame:CGRectMake(10, 20, 220, 30)];  
        labelState.backgroundColor= [UIColorclearColor];  
        [self.viewaddSubview:labelState];  
        [labelStaterelease];  
          
        btnStartVideo= [[UIButtonalloc] initWithFrame:CGRectMake(20, 350, 80, 50)];  
        [btnStartVideosetTitle:@"Star"forState:UIControlStateNormal];  
          
          
        [btnStartVideosetBackgroundImage:[UIImageimageNamed:@"Images/button.png"] forState:UIControlStateNormal];  
        [btnStartVideoaddTarget:selfaction:@selector(startVideoCapture) forControlEvents:UIControlEventTouchUpInside];  
        [self.viewaddSubview:btnStartVideo];  
        [btnStartVideorelease];  
          
        UIButton* stop = [[UIButtonalloc] initWithFrame:CGRectMake(120, 350, 80, 50)];  
        [stop setTitle:@"Stop"forState:UIControlStateNormal];  
          
        [stop setBackgroundImage:[UIImageimageNamed:@"Images/button.png"] forState:UIControlStateNormal];  
        [stop addTarget:selfaction:@selector(stopVideoCapture:) forControlEvents:UIControlEventTouchUpInside];  
        [self.view addSubview:stop];  
        [stop release];  
          
        localView= [[UIViewalloc] initWithFrame:CGRectMake(40, 50, 200, 300)];  
        [self.viewaddSubview:localView];  
        [localViewrelease];  
          
          
        }  
        #pragma mark -  
        #pragma mark VideoCapture  
        - (AVCaptureDevice *)getFrontCamera  
        {  
        //获取前置摄像头设备  
        NSArray *cameras = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];  
            for (AVCaptureDevice *device in cameras)  
        {  
                if (device.position == AVCaptureDevicePositionFront)  
                    return device;  
            }  
            return [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];  
          
        }  
        - (void)startVideoCapture  
        {  
        //打开摄像设备，并开始捕抓图像  
        [labelStatesetText:@"Starting Video stream"];  
        if(self->avCaptureDevice|| self->avCaptureSession)  
        {  
        [labelStatesetText:@"Already capturing"];  
        return;  
        }  
          
        if((self->avCaptureDevice = [self getFrontCamera]) == nil)  
        {  
        [labelStatesetText:@"Failed to get valide capture device"];  
        return;  
        }  
          
        NSError *error = nil;  
            AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:self->avCaptureDevice error:&error];  
            if (!videoInput)  
        {  
        [labelStatesetText:@"Failed to get video input"];  
        self->avCaptureDevice= nil;  
                return;  
            }  
          
            self->avCaptureSession = [[AVCaptureSession alloc] init];  
            self->avCaptureSession.sessionPreset = AVCaptureSessionPresetLow;  
            [self->avCaptureSession addInput:videoInput];  
          
        // Currently, the only supported key is kCVPixelBufferPixelFormatTypeKey. Recommended pixel format choices are   
        // kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange or kCVPixelFormatType_32BGRA.   
        // On iPhone 3G, the recommended pixel format choices are kCVPixelFormatType_422YpCbCr8 or kCVPixelFormatType_32BGRA.  
        //  
            AVCaptureVideoDataOutput *avCaptureVideoDataOutput = [[AVCaptureVideoDataOutput alloc] init];  
        NSDictionary*settings = [[NSDictionaryalloc] initWithObjectsAndKeys:  
        //[NSNumber numberWithUnsignedInt:kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange], kCVPixelBufferPixelFormatTypeKey,  
        [NSNumbernumberWithInt:240], (id)kCVPixelBufferWidthKey,  
                                      [NSNumber numberWithInt:320], (id)kCVPixelBufferHeightKey,  
          nil];  
            avCaptureVideoDataOutput.videoSettings = settings;  
            [settings release];  
            avCaptureVideoDataOutput.minFrameDuration = CMTimeMake(1, self->producerFps);  
        /*We create a serial queue to handle the processing of our frames*/  
        dispatch_queue_tqueue = dispatch_queue_create("org.doubango.idoubs", NULL);  
            [avCaptureVideoDataOutput setSampleBufferDelegate:self queue:queue];  
            [self->avCaptureSession addOutput:avCaptureVideoDataOutput];  
            [avCaptureVideoDataOutput release];  
        dispatch_release(queue);  
          
        AVCaptureVideoPreviewLayer* previewLayer = [AVCaptureVideoPreviewLayer layerWithSession: self->avCaptureSession];  
        previewLayer.frame = localView.bounds;  
        previewLayer.videoGravity= AVLayerVideoGravityResizeAspectFill;  
          
        [self->localView.layer addSublayer: previewLayer];  
          
        self->firstFrame= YES;  
            [self->avCaptureSession startRunning];  
          
        [labelStatesetText:@"Video capture started"];  
          
        }  
        - (void)stopVideoCapture:(id)arg  
        {  
        //停止摄像头捕抓  
        if(self->avCaptureSession){  
        [self->avCaptureSession stopRunning];  
        self->avCaptureSession= nil;  
        [labelStatesetText:@"Video capture stopped"];  
        }  
        self->avCaptureDevice= nil;  
        //移除localView里面的内容  
        for(UIView*viewinself->localView.subviews) {  
        [viewremoveFromSuperview];  
        }  
        }  
        #pragma mark -  
        #pragma mark AVCaptureVideoDataOutputSampleBufferDelegate  
        - (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection   
        {  
        //捕捉数据输出 要怎么处理虽你便  
        CVPixelBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);  
        /*Lock the buffer*/  
        if(CVPixelBufferLockBaseAddress(pixelBuffer, 0) == kCVReturnSuccess)  
        {  
                UInt8 *bufferPtr = (UInt8 *)CVPixelBufferGetBaseAddress(pixelBuffer);  
                size_t buffeSize = CVPixelBufferGetDataSize(pixelBuffer);  
          
        if(self->firstFrame)  
        {   
        if(1)  
        {  
        //第一次数据要求：宽高，类型  
        int width = CVPixelBufferGetWidth(pixelBuffer);  
        int height = CVPixelBufferGetHeight(pixelBuffer);  
          
        int pixelFormat = CVPixelBufferGetPixelFormatType(pixelBuffer);  
        switch (pixelFormat) {  
        casekCVPixelFormatType_420YpCbCr8BiPlanarVideoRange:  
        //TMEDIA_PRODUCER(producer)->video.chroma = tmedia_nv12; // iPhone 3GS or 4  
        NSLog(@"Capture pixel format=NV12");  
        break;  
        casekCVPixelFormatType_422YpCbCr8:  
        //TMEDIA_PRODUCER(producer)->video.chroma = tmedia_uyvy422; // iPhone 3  
        NSLog(@"Capture pixel format=UYUY422");  
        break;  
        default:  
        //TMEDIA_PRODUCER(producer)->video.chroma = tmedia_rgb32;  
        NSLog(@"Capture pixel format=RGB32");  
        break;  
        }  
          
        self->firstFrame = NO;  
        }  
        }  
        /*We unlock the buffer*/  
        CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);   
            }  
        /*We create an autorelease pool because as we are not in the main_queue our code is  
         not executed in the main thread. So we have to create an autorelease pool for the thread we are in*/  
        // NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];  
        //   
        //    CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);   
        //    /*Lock the image buffer*/  
        //    CVPixelBufferLockBaseAddress(imageBuffer,0);   
        //    /*Get information about the image*/  
        //    uint8_t *baseAddress = (uint8_t *)CVPixelBufferGetBaseAddress(imageBuffer);   
        //    size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);   
        //    size_t width = CVPixelBufferGetWidth(imageBuffer);   
        //    size_t height = CVPixelBufferGetHeight(imageBuffer);    
        //      
        //    /*Create a CGImageRef from the CVImageBufferRef*/  
        //    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();   
        //    CGContextRef newContext = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);  
        //    CGImageRef newImage = CGBitmapContextCreateImage(newContext);   
        //   
        //    /*We release some components*/  
        //    CGContextRelease(newContext);   
        //    CGColorSpaceRelease(colorSpace);  
        //      
        //    /*We display the result on the custom layer. All the display stuff must be done in the main thread because  
        //  UIKit is no thread safe, and as we are not in the main thread (remember we didn't use the main_queue)  
        //  we use performSelectorOnMainThread to call our CALayer and tell it to display the CGImage.*/  
        // [self.customLayer performSelectorOnMainThread:@selector(setContents:) withObject: (id) newImage waitUntilDone:YES];  
        //   
        // /*We display the result on the image view (We need to change the orientation of the image so that the video is displayed correctly).  
        //  Same thing as for the CALayer we are not in the main thread so ...*/  
        // UIImage *image= [UIImage imageWithCGImage:newImage scale:1.0 orientation:UIImageOrientationRight];  
        //   
        // /*We relase the CGImageRef*/  
        // CGImageRelease(newImage);  
        //   
        // [self.imageView performSelectorOnMainThread:@selector(setImage:) withObject:image waitUntilDone:YES];  
        //   
        // /*We unlock the  image buffer*/  
        // CVPixelBufferUnlockBaseAddress(imageBuffer,0);  
        //   
        // [pool drain];  
        }  
        @end