ios - 如何优化过滤器性能 CIFilter

Question

static func effectTransfer(image: UIImage) -> UIImage {
    let coreImage = CIImage(image: image)
    let filter = CIFilter(name: "CIPhotoEffectTransfer" )
    filter!.setDefaults()
    filter!.setValue(coreImage, forKey: kCIInputImageKey)
    let filteredImageData = filter!.value(forKey: kCIOutputImageKey) as! CIImage
    let filteredImageRef = ciContext.createCGImage(filteredImageData, from: filteredImageData.extent)

    return UIImage(cgImage: filteredImageRef!)
}

当您点击某个滤镜时，该滤镜的应用速度极其缓慢，并且处理器在一两秒内增长到 60%，我该如何优化它？我这样做对吗？

Answer 1

最慢的部分是转换为 CGImage。您可以直接从 CIImage 创建 UIImage:

UIImage(ciImage: outputCI, scale: input.scale, orientation: input.imageOrientation)