swift - CGImage 到 CVPixelBuffer

Question

如何转换 CGImage到 CVPixelBuffer swift ？

我知道很多问题试图做相反的事情，还有一些客观的 C 答案，比如 this one但我无法让他们 swift 工作。这是我得到的最接近的:

func pixelBufferFromCGImage(image: CGImage) -> CVPixelBuffer {
    var pxbuffer: CVPixelBuffer? = nil
    let options: NSDictionary = [:]

    let width =  image.width
    let height = image.height
    let bytesPerRow = image.bytesPerRow

    let dataFromImageDataProvider = image.dataProvider!.data
    let x = CFDataGetBytePtr(dataFromImageDataProvider)

    CVPixelBufferCreateWithBytes(
        kCFAllocatorDefault,
        width,
        height,
        kCVPixelFormatType_32ARGB,
        CFDataGetBytePtr(dataFromImageDataProvider),
        bytesPerRow,
        nil,
        nil,
        options,
        &pxbuffer
    )
    return pxbuffer!;
}

(这不会编译，因为 CVPixelBufferCreateWithBytes 除了一个 UnsafeMutablePointer 而 CFDataGetBytePtr(dataFromImageDataProvider) 是一个 UnsafePointer<UIint8>! )

Answer 1

您需要使用 UnsafeMutablePointer，为此，您可以将 CFData 转换为 CFMutableData，然后获取 UnsafeMutablePointer 例如:

let dataFromImageDataProvider = CFDataCreateMutableCopy(kCFAllocatorDefault, 0, image.dataProvider!.data)
let x = CFDataGetMutableBytePtr(dataFromImageDataProvider)