Swift无法从UIImage中删除CIFIlter [英] Swift Cannot remove CIFIlter from UIImage

问题描述

现在正在研究swift，并且无法解决这个Core Image Framework问题。我能够在图像上成功创建CIFilter但是我不确定如何删除它。图像被放置在类似于Snapchat的相机屏幕的UIView上，然后有一个图像视图，它是预览图像的uiview的子视图。 BTW使用最新版本的Xcode和iOS。

been working on swift for a bit now and having trouble tackling this Core Image Framework. I was able to successfully create a CIFilter over an image however I'm not sure how to delete it. The Image Is placed over a UIView which resembles that of snapchat's camera screen and then there is an imageview which is a subview of the uiview that the image is previewed on. BTW Using The most up to date version of Xcode and iOS as well.

以下是应用黑白滤镜时的代码：

Here is the code for when the black and white filter is applied:

@IBAction func BW_Flt_Bt_Tapped(sender: UIButton) {
    let beginImage = CIImage(image: imagePreview.image!)
    let ciContext = CIContext(options: nil)
    let filter = CIFilter(name: "CIPhotoEffectNoir")
    var imgOrientation = imagePreview.image!.imageOrientation
    var imgScale = imagePreview.image?.scale
    filter!.setDefaults()
    filter!.setValue(beginImage, forKey: kCIInputImageKey)
    let filteredImageData = filter!.valueForKey(kCIOutputImageKey) as! CIImage
    let filteredImageRef = ciContext.createCGImage(filteredImageData, fromRect: filteredImageData.extent)
    imagePreview.image = UIImage(CGImage: filteredImageRef, scale: 1.0, orientation: UIImageOrientation.Right)
    self.orgImgBt.hidden = false
    self.orgImgL.hidden = false
    BWFlt.hidden = true
    BWLbl.hidden = true





}

-imagePreview是UIView的子视图

-imagePreview is the subview of the UIView

接下来是我的代码如何更改图像

Next is my code for how to change the image back

@IBAction func orgImgPressed(sender: UIButton) {
     self.imagePreview.image = self.selctedImage
    orgImgBt.hidden = true
    orgImgL.hidden = true
   `enter code here` BWFlt.hidden = false
    `enter code here`BWLbl.hidden = false


            print("button was pressed")
        }

如果有人有任何建议我会非常感激，谢谢！

If anyone had any suggestions I would be very appreciative, Thanks!

推荐答案

您可以通过将先前值保留在变量中，或者如果您有多个过滤器将这些值保存在字典。当您应用新过滤器或更改现有过滤器的值时，只需将该值替换为新值并应用原始CIImage上的所有值

You can do this by keeping previous value in a variable or if you have multiple filters keep that values in a dictionary. When you are applying a new filter or changing value of existing filter, just replace that value with new value and apply all values on original CIImage

例如，

    var allFilters = [String: [String: Any]]()
    var currentImage: CIImage!
    let kCIColorControls = "CIColorControls"

    override func viewDidLoad() {
        super.viewDidLoad()
        currentImage = CIImage(image: self.originalImage!)
    }

    func applyAvailableFilters() {
            if self.allFilters.count > 0 {            
                DispatchQueue.global(qos: .background).async {
                    var outputImage: CIImage!

                    self.blurFilter = CIFilter.init(name: "CIGaussianBlur")
                    self.brightnessFilter = CIFilter.init(name: "CIColorControls")
                    self.cropFilter = CIFilter.init(name: "CICrop")

                    if let blurProperty = self.allFilters[self.kCIGaussianBlur]?.first {
                        self.blurFilter.setValue(blurProperty.value, forKey: blurProperty.key)
                                                self.blurFilter.setValue(self.currentImage, forKey: kCIInputImageKey)
                        outputImage = self.blurFilter.outputImage
                    }

                    if let brightnessProperty = self.allFilters[self.kCIColorControls]?.first {
                        self.brightnessFilter.setValue(brightnessProperty.value, forKey: brightnessProperty.key)
                        if let outputImage = self.blurFilter.outputImage {
                            self.brightnessFilter.setValue(outputImage, forKey: kCIInputImageKey)
                        } else {
                            self.brightnessFilter.setValue(self.currentImage, forKey: kCIInputImageKey)
                        }
                        outputImage = self.brightnessFilter.outputImage
                    }

                    if let cropProperty = self.allFilters[self.kCICrop]?.first {
                        self.cropFilter.setValue(cropProperty.value, forKey: cropProperty.key)
                        if let outputImage = self.brightnessFilter.outputImage {
                            self.cropFilter.setValue(outputImage, forKey: kCIInputImageKey)
                        } else if let outputImage = self.blurFilter.outputImage {
                            self.cropFilter.setValue(outputImage, forKey: kCIInputImageKey)
                        } else {
                            self.cropFilter.setValue(self.currentImage, forKey: kCIInputImageKey)
                        }
                        outputImage = self.cropFilter.outputImage
                    }

                    if let image = outputImage {
                        let openGLContext = EAGLContext(api: .openGLES2)
                        let context = CIContext(eaglContext: openGLContext!)
                        if let cgimg = context.createCGImage(image, from: image.extent) {
                            let processedImage = UIImage(cgImage: cgimg)
                            DispatchQueue.main.async {
                                self.imageView.image = processedImage
                            }
                        }
                    } else {
                        DispatchQueue.main.async {
                            self.imageView.image = self.selectedImage
                        }
                    }
                }
            } else {
                DispatchQueue.main.async {
                    self.imageView.image = self.selectedImage
                }
            }
        }

然后像这样应用你的过滤器（模糊过滤器）

Then apply your filter like this (Blur filter)

@IBAction func sliderValueChanged(_ sender: UISlider) {
      if sender.value == 0 {
            _ = allFilters.removeValue(forKey: kCIGaussianBlur)
        } else {
            allFilters[kCIGaussianBlur] = [kCIInputRadiusKey: sender.value]
        }
        if allFilters[kCICrop]?.first == nil {
            allFilters[kCICrop] = ["inputRectangle": CIVector(cgRect: self.currentImage.extent)]
        }
        applyAvailableFilters()
}

这篇关于Swift无法从UIImage中删除CIFIlter的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！