NSImage vs. CIImage vs. CGImage

NSImage vs. CIImage vs. CGImage：三者之间的区别与应用

swift
import Cocoa
// 加载图片
let image = NSImage(named: "example.jpg")
// 显示图片
let imageView = NSImageView(frame: NSRect(x: 0, y: 0, width: 200, height: 200))
imageView.image = image
// 添加到视图中
let view = NSView(frame: NSRect(x: 0, y: 0, width: 400, height: 400))
view.addSubview(imageView)

swift
import CoreImage
// 加载图片
let image = CIImage(contentsOf: URL(fileURLWithPath: "example.jpg"))
// 创建滤镜
let filter = CIFilter(name: "CIPhotoEffectMono")
filter?.setValue(image, forKey: kCIInputImageKey)
// 处理图像
let outputImage = filter?.outputImage
// 将图像转换为CGImage
let context = CIContext()
let cgImage = context.createCGImage(outputImage, from: outputImage.extent)
// 显示图像
let imageView = NSImageView(frame: NSRect(x: 0, y: 0, width: 200, height: 200))
imageView.image = NSImage(cgImage: cgImage!, size: NSSize(width: 200, height: 200))
// 添加到视图中
let view = NSView(frame: NSRect(x: 0, y: 0, width: 400, height: 400))
view.addSubview(imageView)

swift
import CoreGraphics
// 加载图片
let image = CGImage(imageLiteralResourceName: "example.jpg")
// 获取图像的宽度和高度
let width = image.width
let height = image.height
// 创建上下文
let colorSpace = CGColorSpaceCreateDeviceRGB()
let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedLast.rawValue)
let context = CGContext(data: nil, width: width, height: height, bitsPerComponent: 8, bytesPerRow: 0, space: colorSpace, bitmapInfo: bitmapInfo.rawValue)
// 绘制图像
context?.draw(image, in: CGRect(x: 0, y: 0, width: width, height: height))
// 获取图像数据
let data = context?.data
// 对图像数据进行操作...
// 创建新的CGImage对象
let newImage = context?.makeImage()
// 显示图像
let imageView = NSImageView(frame: NSRect(x: 0, y: 0, width: 200, height: 200))
imageView.image = NSImage(cgImage: newImage!, size: NSSize(width: 200, height: 200))
// 添加到视图中
let view = NSView(frame: NSRect(x: 0, y: 0, width: 400, height: 400))
view.addSubview(imageView)