自定义相机裁剪图片

目前正好需要做裁剪图片，且支持相机拍摄后，按照规定大小裁剪，这里记录一下

首先初始化摄像头

    self.session = [[AVCaptureSession alloc] init];
    self.session.sessionPreset = AVCaptureSessionPresetHigh;
    NSError *error;
    
    self.effectiveScale = 1.0;
    
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    
    [device lockForConfiguration:nil];
    if ([device isExposureModeSupported:AVCaptureExposureModeContinuousAutoExposure]) {
        [device setExposureMode:AVCaptureExposureModeContinuousAutoExposure];
    }
    
    [device unlockForConfiguration];
    
    self.videoInput = [[AVCaptureDeviceInput alloc] initWithDevice:device error:&error];
    if (error) {
        NSLog(@"%@",error);
    }
    self.stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
    //输出设置。AVVideoCodecJPEG   输出jpeg格式图片
    NSDictionary * outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys:AVVideoCodecJPEG,AVVideoCodecKey, nil];
    [self.stillImageOutput setOutputSettings:outputSettings];
    
    if ([self.session canAddInput:self.videoInput]) {
        [self.session addInput:self.videoInput];
    }
    if ([self.session canAddOutput:self.stillImageOutput]) {
        [self.session addOutput:self.stillImageOutput];
    }
    
    //初始化预览图层
    self.previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.session];
    [self.previewLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
    
    self.previewLayer.frame = CGRectMake(0, 0,kGZIM_SCREEN_WIDTH, kGZIM_SCREEN_HEIGHT);
    self.view.layer.masksToBounds = YES;
    [self.view.layer addSublayer:self.previewLayer];

点击拍照后，用下面的方式获取图片

 - (void)takePhotoButtonClick {
    _stillImageConnection = [self.stillImageOutput        connectionWithMediaType:AVMediaTypeVideo];
    UIDeviceOrientation curDeviceOrientation = [[UIDevice currentDevice] orientation];
    AVCaptureVideoOrientation avcaptureOrientation = [self avOrientationForDeviceOrientation:curDeviceOrientation];
    [_stillImageConnection setVideoOrientation:avcaptureOrientation];
    
    [self.stillImageOutput captureStillImageAsynchronouslyFromConnection:_stillImageConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
        
        NSData *jpegData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
        
        UIImage *img = [UIImage imageWithData:jpegData];
        
        NSLog(@"%f   %f",img.size.width,img.size.height);
        
        img = [self image:img scaleToSize:CGSizeMake(kGZIM_SCREEN_WIDTH, kGZIM_SCREEN_HEIGHT)];
        //CGRectMake(30, 200, kDeviceWidth-60, kDeviceHeight-200-300)
        CGRect rc = self.clipRect;
        rc.origin.x *= 2;
        rc.origin.y *= 2;
        rc.size.width *= 2;
        rc.size.height *= 2;
        img = [self imageFromImage:img inRect:rc];
    }];
}

-(UIImage*)image:(UIImage *)imageI scaleToSize:(CGSize)size{
    UIGraphicsBeginImageContextWithOptions(size, NO, 2.0);
    [imageI drawInRect:CGRectMake(0, 0, size.width, size.height)];
    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return scaledImage;
}

-(UIImage *)imageFromImage:(UIImage *)imageI inRect:(CGRect)rect{
    CGImageRef sourceImageRef = [imageI CGImage];
    CGImageRef newImageRef = CGImageCreateWithImageInRect(sourceImageRef, rect);
    UIImage *newImage = [UIImage imageWithCGImage:newImageRef];
    return newImage;
}

到此就结束了,最后附上一个截图

21539863423_.pic.jpg

demo放在后面的从相册选择图片并裁剪的文章中