如何在图像中创建边缘检测滤镜？

Question

Swift 5.0

我有一个任务要在图像中创建这种类型的输出，以便如何应用渐变的边框和边框颜色。请在下面看到为我工作的同一任务的图像。

查看原始图片

我需要此输出

Answer 1

尝试 迅速5

pod 'GPUImage'

UIImagePickerControllerDelegate , UINavigationControllerDelegate

import GPUImage

@IBAction func selectPhotoButtonClick(_ sender: UIButton) {
        let picker = UIImagePickerController.init()
        picker.delegate = self
        picker.allowsEditing = true
        picker.sourceType = .photoLibrary
        self.present(picker, animated: true, completion: nil)
    }

@IBAction func detectEdgeButtonClick(_ sender: Any) {
        self.GPUResult()
}

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        let img = info[UIImagePickerController.InfoKey.editedImage] as? UIImage
        self.dismiss(animated: true) {
            self.ivImage.image = img!
            self.uploadImage(img: img!)
        }
    }

func uploadImage(img : UIImage) {
    let heder = ["User-Agent" : "Dalvik/2.1.0 (Linux; U; Android 5.1; 1201 Build/LMY47I)",
                 "Host" : "prodml.dexati.com",
                 "Connection" : "Keep-Alive",
                 "Accept-Encoding" : "gzip"]
    let imgData = img.jpegData(compressionQuality: 1.0)
    Alamofire.upload(
        multipartFormData: { MultipartFormData in
            MultipartFormData.append(imgData!, withName: "file", fileName: "file.jpeg", mimeType: "image/jpeg")
    }, to: "http://prodml.dexati.com/DexNewGrabcut", method: .post, headers: heder)
    { (result) in
        switch result {
        case .success(let response, _, _):
            response.responseData(completionHandler: { (DataResponse) in
                if DataResponse.result.value != nil {
                    if let i = UIImage.init(data: DataResponse.result.value!) {
                        let maskLayer = CALayer()
                        let mask = i
                        maskLayer.contents = mask.cgImage
                        maskLayer.contentsGravity = .resizeAspect
                        maskLayer.frame = self.ivImage.frame
                        self.viewMain.layer.mask = maskLayer
                        self.inputImage = self.ivImage.image
                    }
                    else
                    {
                        print("error63==>",DataResponse.error?.localizedDescription)
                    }
                } else
                {
                    print("error67==>",DataResponse.error?.localizedDescription)
                }
            })

        case .failure(let encodingError): break
        }
    }
}

func GPUResult(){
        var image_p: GPUImagePicture?
        if let anImage = inputImage {
            image_p = GPUImagePicture(image: anImage)
        }

        let filter1 = GPUImageCannyEdgeDetectionFilter()//GPUImageSobelEdgeDetectionFilter()
        image_p?.addTarget(filter1)
        image_p?.processImage()

        let outputImage = filter1.newCGImage(byFilteringImage: inputImage)
        let finalImage = UIImage(cgImage: (outputImage?.takeRetainedValue())!)
        ivImage.image = finalImage
    }