AVfoundation中焦距的设置(slider实现拉近拉远镜头) -自定义UISlider

焦距AVfoundation调节焦距

首先设置一个slider

UISlider focusSlider = [[UISlideralloc]initWithFrame:CGRectMake(60,_bottomView.frame.origin.y-60,200,20)];

    [focusSlideraddTarget:selfaction:@selector(AdjustFocusAction:)forControlEvents:UIControlEventValueChanged];

    [focusSlidersetThumbImage:[UIImageimageNamed:@"camera_view_slider_take_gray.png"]forState:UIControlStateNormal];

    [focusSlidersetMinimumTrackImage:[UIImageimageNamed:@"camera_view_sliderbar_gray.png"]forState:UIControlStateNormal];

    [focusSlidersetMaximumTrackImage:[UIImageimageNamed:@"camera_view_sliderbar_gray.png"]forState:UIControlStateNormal];

    [focusSlidersetBackgroundColor:[UIColorclearColor]];

    [focusSlidersetMaximumValue:1];

    [focusSlidersetMinimumValue:0];

    [focusSlider setValue:0.0];

    [self.viewaddSubview:focusSlider];

以下做一下有关相机的设置（只写出来了其中一部分，并非全部）

preview = [AVCaptureVideoPreviewLayerlayerWithSession:self.session];

    self.preview.frame =CGRectMake(0,0, self.cameraView.frame.size.width,self.cameraView.frame.size.height);

    [self.previewsetPosition:CGPointMake(CGRectGetMidX(self.cameraView.bounds),CGRectGetMidY(self.cameraView.bounds))];

   

    self.preview.videoGravity =AVLayerVideoGravityResize;

    [self.cameraView.layeraddSublayer:self.preview];

captureOutput = (AVCaptureStillImageOutput*)[self.session.outputsobjectAtIndex:0];

 

focusConnection =[captureOutput connectionWithMediaType:AVMediaTypeVideo];    

                                                          

调节焦距

 

-(void)AdjustFocusAction:(id)sender

{

    [UIViewanimateWithDuration:0.025animations:^{

        [self.previewsetAffineTransform:CGAffineTransformMakeScale([(UISlider *)sendervalue]+1, [(UISlider *)sendervalue]+1)];

        focusConnection.videoScaleAndCropFactor = [(UISlider *)sendervalue]+1;

    }];

}