ios - 无法识别的选择器发送到实例 - 如何修复 : Error Loading picture from photo album

Question

尝试从相册加载图片时出现以下错误，我不确定原因:无法识别的选择器发送到实例下面是我的代码，下面是我的错误堆栈的一部分:

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSCFNumber extent]: unrecognized selector sent to instance 0x60000022d440' *** First throw call stack: ( 0 CoreFoundation 0x000000010efe21e6 __exceptionPreprocess + 294 1 libobjc.A.dylib 0x000000010d1e9031 objc_exception_throw + 48 2 CoreFoundation 0x000000010f063784 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132 3 CoreFoundation 0x000000010ef64898 ___forwarding_ + 1432 4 CoreFoundation 0x000000010eff5d28 forwarding_prep_1_ + 120 5 CoreImage 0x000000010daecf17 -[CISepiaTone outputImage] + 152

请在下面找到我的源代码:

import UIKit
import CoreImage

class ViewController: UIViewController,  UINavigationControllerDelegate {
    //outlet for image to be filtered
    @IBOutlet weak var imageToFilter: UIImageView!

    //outlet for slider to manipulate intensity as slider is dragged
    @IBOutlet weak var filterIntensity: UISlider!

    //property to store UIImage containing the image selected by user from photo album
    var currentImage: UIImage!

    //context from CoreImage Framework to handle rendering of the image for Wakanda Filter
    var imageContext: CIContext!

    //CoreImage Filter to store filters selected by the user
    var currentImageFilters: CIFilter!

    override func viewDidLoad() {
        super.viewDidLoad()

        //objects of coreContext and coreFilterd
        imageContext = CIContext()
        currentImageFilters = CIFilter(name: "CISepiaTone")

        //title to appear on nav
        title = "Wakanda Filter"
        navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(importPictureFromAlbum))
    }

    //action to update UI when user increases or decreases intensity
    @IBAction func intensityValueChanged(_ sender: UISlider) {
        processImageWithFilter()
    }

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo  info: [String : Any]) {
        guard let imageSelected = info[UIImagePickerControllerEditedImage] as? UIImage else {
            return
        }

        dismiss(animated: true)

        currentImage = imageSelected

        //setting imported image as value to Filter object then manipulating
        let initialImageForFilters = CIImage(image: currentImage)
        currentImageFilters.setValue(initialImageForFilters, forKey: kCIInputImageKey)

        //calling on method to process the image
        processImageWithFilter()
    }

    func processImageWithFilter(){
        currentImageFilters.setValue(filterIntensity.value, forKey: kCIInputImageKey)
        if let computerGeneratedImage = imageContext.createCGImage(currentImageFilters.outputImage!, from: currentImageFilters.outputImage!.extent){
            let processedImage = UIImage(cgImage: computerGeneratedImage)
            self.imageToFilter.image = processedImage
        }
    }
}

extension ViewController: UIImagePickerControllerDelegate {
    //objective c method to control method for selector how to import picture from album
    @objc func importPictureFromAlbum(){
        //creating an object of UIImagePickerController class (will allow editing of images too by modifying Info.plist
        let imagePicker = UIImagePickerController()

        //allow editing of the image
        imagePicker.allowsEditing = true

        //assigning delegate
        imagePicker.delegate = self

        present(imagePicker, animated: true)
    }
}

Answer 1

CISepiaTone 过滤器需要两个参数:

inputImage: A CIImage object whose display name is Image.

inputIntensity: An NSNumber object whose attribute type is CIAttributeTypeScalar and whose display name is Intensity.

您的错误来自这一行:

currentImageFilters.setValue(filterIntensity.value, forKey: kCIInputImageKey)

将值更改为图像或将键更改为kCIInputIntensityKey。

鉴于您之前设置了图像，您可能想要更改此行上的键。

currentImageFilters.setValue(filterIntensity.value, forKey: kCIInputIntensityKey)