如何从CVPixelBuffer创建CGImage？

Question

我有一个简单的函数，可以从 CVPixelBuffer 创建 CGImage:

if let buffer = (results as? [VNPixelBufferObservation])?.first {
    let pixelBuffer = buffer.pixelBuffer
    let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
    let resultImage = UIImage(ciImage: ciImage)
    return resultImage.cgImage //returns nil
}

但它返回了nil。为什么？

- Bartłomiej Semańczyk

---

你试过这个吗？ - undefined

Answer 1

输出为nil是因为您使用CIImage而不是CGImage创建了UIImage实例。以下是创建CGImage的方法：

func createCGImage(from pixelBuffer: CVPixelBuffer) -> CGImage? {
   let ciContext = CIContext()
   let ciImage = CIImage(cvImageBuffer: pixelBuffer)
   return ciContext.createCGImage(ciImage, from: ciImage.extent)
}

- Asteroid

Answer 2

试试这个

import VideoToolbox
func createImage(from pixelBuffer: CVPixelBuffer) -> CGImage? {
    var cgImage: CGImage?
    VTCreateCGImageFromCVPixelBuffer(pixelBuffer, options: nil, imageOut: &cgImage)
    return cgImage
}

- Alexander Gaidukov