使用Swift上的GPUImage过滤器捕获图像

Question

I'm using GPUImage Framework for Image filters.

I have applied the ToonFilter() on camera for cartoon filter effect.

My issue is while capture image on camera with ToonFilter effect with GPUImage.

Below is the code to show the ToonFilter with GPUImage camera & to capture a new image with the same effect.

Please guide me how I may capture an image with the same filter?

Note : I am successfully able to open camera with ToonFilter effect - the issue is only with capture a new image with a filter effect.

Code :

import UIKit
import GPUImage
import AVFoundation

class SelfieFilterVC: UIViewController, UISplitViewControllerDelegate  {

    @IBOutlet var filterSlider: UISlider?
    @IBOutlet var filterView: RenderView?

    let videoCamera:Camera?
    var blendImage:PictureInput?

    override func viewDidLoad() {

        super.viewDidLoad()

        self.filterOperation = FilterOperation(
            filter:{ToonFilter()},
            listName:"Toon",
            titleName:"Toon",
            sliderConfiguration:.disabled,
            sliderUpdateCallback: nil,
            filterOperationType:.singleInput
        )

        self.configureView()
    }

    required init(coder aDecoder: NSCoder)
    {
        do {
            videoCamera = try Camera(sessionPreset:AVCaptureSessionPreset640x480, location:.backFacing)
            videoCamera!.runBenchmark = true

        } catch {
            videoCamera = nil
            print("Couldn't initialize camera with error: \(error)")
        }

        super.init(coder: aDecoder)!
    }

    var filterOperation: FilterOperationInterface?


    @IBAction func btnCapture(_ sender: Any) {

        videoCamera?.startCapture()

        let pictureOutput = PictureOutput()
        pictureOutput.encodedImageFormat = .jpeg
        pictureOutput.encodedImageAvailableCallback = {imageData in

            if imageData != nil {
                let captureDetailVC = self.storyboard?.instantiateViewController(withIdentifier: "CaptureDetailVC") as! CaptureDetailVC
                captureDetailVC.aCaptureSelectedData = imageData
                self.show(captureDetailVC, sender: true)
            }
        }
    }

    @IBAction func btnBackAction(_ sender: Any) {
        self.dismiss(animated: true, completion: nil)
    }
    func configureView() {

        guard let videoCamera = videoCamera else {

            let errorAlertController = UIAlertController(title: NSLocalizedString("Error", comment: "Error"), message: "Couldn't initialize camera", preferredStyle: .alert)
            errorAlertController.addAction(UIAlertAction(title: NSLocalizedString("OK", comment: "OK"), style: .default, handler: nil))
            self.present(errorAlertController, animated: true, completion: nil)
            return
        }

        if let currentFilterConfiguration = self.filterOperation {
            self.title = currentFilterConfiguration.titleName

            // Configure the filter chain, ending with the view
            if let view = self.filterView {
                switch currentFilterConfiguration.filterOperationType {
                case .singleInput:
                    videoCamera.addTarget(currentFilterConfiguration.filter)
                    currentFilterConfiguration.filter.addTarget(view)
                case .blend:
                    videoCamera.addTarget(currentFilterConfiguration.filter)
                    self.blendImage = PictureInput(imageName:blendImageName)
                    self.blendImage?.addTarget(currentFilterConfiguration.filter)
                    self.blendImage?.processImage()
                    currentFilterConfiguration.filter.addTarget(view)
                case let .custom(filterSetupFunction:setupFunction):
                    currentFilterConfiguration.configureCustomFilter(setupFunction(videoCamera, currentFilterConfiguration.filter, view))
                }

                videoCamera.startCapture()
            }

            // Hide or display the slider, based on whether the filter needs it
            if let slider = self.filterSlider {
                switch currentFilterConfiguration.sliderConfiguration {
                case .disabled:
                    slider.isHidden = true
                //                case let .Enabled(minimumValue, initialValue, maximumValue, filterSliderCallback):
                case let .enabled(minimumValue, maximumValue, initialValue):
                    slider.minimumValue = minimumValue
                    slider.maximumValue = maximumValue
                    slider.value = initialValue
                    slider.isHidden = false
                    self.updateSliderValue()
                }
            }

        }
    }

    @IBAction func updateSliderValue() {
        if let currentFilterConfiguration = self.filterOperation {
            switch (currentFilterConfiguration.sliderConfiguration) {
            case .enabled(_, _, _): currentFilterConfiguration.updateBasedOnSliderValue(Float(self.filterSlider!.value))
            case .disabled: break
            }
        }
    }



    override func viewWillDisappear(_ animated: Bool) {
        if let videoCamera = videoCamera {
            videoCamera.stopCapture()
            videoCamera.removeAllTargets()
            blendImage?.removeAllTargets()
        }

        super.viewWillDisappear(animated)
    }
}

Answer 1

The way you capture an image with GPUImage is with the method imageFromCurrentFramebuffer that you can user con your filter.

It returns a UIImage which you can later convert to whatever image format you need and save it.

let image:UIImage = filter.imageFromCurrentFramebuffer()
if let data = UIImageJPEGRepresentation(image, 0.8) {
    let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
    let filename = documentsDirectory.appendingPathComponent("image.jpg")
    try? data.write(to: filename)
}