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将CGImage转换为NSImage的Swift方法

swiftnsimagecgimage
4

我正在尝试在NSImageView框中显示CGImage，但我无法将CGImage转换为NSImage。我应该如何处理这种情况？谢谢！

3
以下是需要翻译的内容：https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Classes/NSImage_Class/#//apple_ref/occ/instm/NSImage/initWithCGImage:size: init(CGImage cgImage: CGImage, size size: NSSize)? https://dev59.com/gGox5IYBdhLWcg3wmFaV ?这段文字介绍了一个在苹果开发中常用的类NSImage的初始化方法init(CGImage cgImage: CGImage, size size: NSSize)，并提供了一个指向使用该方法获取NSImage对象的Stack Overflow问题链接。 - Larme
非常感谢！显然，当我尝试初始化时，我忽略了NSSize参数的正确初始化... :D - ch_studend
1个回答
5

部分参考 Larme 的评论：

  • for Swift, the NSImage initializer that takes a CGImage is init(cgImage:size:) and a syntax example is:

    let myNsImage = NSImage(cgImage: myCgImage, size: .zero)

    .zero is a convenience for using the same size as the CGImage.

  • for Objective-C, see Getting NSImage from CGImageRef.

作为简化演示（有意使用 !），这个 macOS Playground 将以可视化方式呈现与编程生成的 cgImage 相同的 nsImage：

import AppKit
let colorSpace = CGColorSpaceCreateDeviceRGB()
let bitmapInfo = CGBitmapInfo.byteOrder32Big.rawValue | CGImageAlphaInfo.premultipliedLast.rawValue & CGBitmapInfo.alphaInfoMask.rawValue
let s: UInt32 = 0xffbbbbbb, o: UInt32 = 0xff3d85e6, f: UInt32 = 0x00000000
let width = 12; let height = 15
var pixels = [
    f, f, f, f, f, f, f, o, f, f, f, f, f, f, f, f, f, f, f, o, f, f, f, f, f, f, f, f, f, f, f, f, o, f, f, f, f, f, f, o, f, f, f, f, o, f, f, f, f, f, f, f, o, f, f, f, f, o, f, f, f, f, f, f, f, o, f, f, f, o, f, f, f, f, f, f, f, f, o, f, f, f, o, f, f, f, f, f, f, f, f, o, o, f, f, o, f, f, o, o, f, f, f, f, f, o, o, f, f, f, f, f, o, o, o, o, f, f, f, f, s, f, f, f, f, f, f, f, o, o, f, s, s, f, f, f, f, f, f, f, f, f, f, s, s, f, o, o, o, o, o, o, o, o, f, s, s, f, f, f, f, f, f, f, f, f, f, s, s, s, s, s, s, s, s, s, s, s, s, s,
]
var context: CGContext!
pixels.withUnsafeMutableBufferPointer { bufferPointer in
    context = CGContext(data: bufferPointer.baseAddress, width: width, height: height, bitsPerComponent: 8, bytesPerRow: width * 4, space: colorSpace, bitmapInfo: bitmapInfo, releaseCallback: nil, releaseInfo: nil)
}
let cgImage = context.makeImage()!
let nsImage = NSImage(cgImage: cgImage, size: .zero)
_ = nsImage
网页内容由stack overflow 提供, 点击上面的
可以查看英文原文，
原文链接