使用 CIFilter 应用于 UIImage 和旋转图像的过滤器

Question

当我应用 UIImage 滤镜时，图像的结果是旋转了！我试过这个：

var filterNames: [String] = ["CIPhotoEffectTonal","CIPhotoEffectNoir","CIMaximumComponent","CIMinimumComponent","CIDotScreen", "CISepiaTone", "CIFalseColor", "CIColorInvert", "CIColorPosterize", "CIPhotoEffectChrome", "CIPhotoEffectInstant"]

    let CIfilterName = filterNames[indexPath.row]
    print(CIfilterName)

    let ciContext = CIContext(options: nil)
    let startImage = CIImage(image: originalImage)

    let filter = CIFilter(name: CIfilterName)
    filter!.setDefaults()

    filter!.setValue(startImage, forKey: kCIInputImageKey)
    let filteredImageData = filter!.valueForKey(kCIOutputImageKey) as! CIImage
    let filteredImageRef = ciContext.createCGImage(filteredImageData, fromRect: filteredImageData.extent)

    let originalOrientation: UIImageOrientation = (imageView.image?.imageOrientation)!
    let originalScale: CGFloat = (imageView.image?.scale)!
    let newPtImage: UIImage = UIImage.imageWithCGImage(filteredImageRef, scale: originalScale, orientation: originalOrientation)
    imageView.image = newPtImage

    imageView.image = UIImage(CGImage: filteredImageRef);

规模的最后一部分是我尝试过的，但我展示了那部分代码，这样你就可以看到我做错了什么或者我不知道什么。

我找到了这个答案，但它在 Objective-c 中：Whosebug answer in obj-c

Answer 1

您可以尝试使用带扩展名的 UIImageOrientation to fix this issue, but I definitely recommend switch (Github 示例) 语句，因为稍后当照片上传到服务器时，它可能还会再次改变其方向。

示例：

UIImage(CGImage: imageRef, scale: 1.0, orientation: UIImageOrientation.Right)

Answer 2

当图像高度大于图像宽度时会出现此问题，因此如果您的图像高度大于宽度，那么您应该在应用 CIFilter 之前通过相互交换图像高度和宽度来调整图像大小....

使用 CIFilter 应用于 UIImage 和旋转图像的过滤器

Filter applied to UIImage and rotated image using CIFilter

objective-c

ios

cifilter

swift

示例：