CIImageをCVPixelBufferにします。

１、CVPixelBufferをつくります。

var pixelBuffer: CVPixelBuffer?
let attrs = [kCVPixelBufferCGImageCompatibilityKey: kCFBooleanTrue,
             kCVPixelBufferCGBitmapContextCompatibilityKey: kCFBooleanTrue] as CFDictionary

let width:Int = 256
let height:Int = 256
//　欲しいサイズ

CVPixelBufferCreate(kCFAllocatorDefault,
                    width,
                    height,
                    kCVPixelFormatType_32BGRA,
                    attrs,
                    &pixelBuffer)

2,CVPixelBufferにCIImageをレンダリングします。　

let context = CIContext()
context.render(ciImage, to: pixelBuffer!)

extensionにしておくと、CIImage.pixelBuffer( )でかんたんにPixelBufferを取得できます。

extension CIImage {
    func pixelBuffer(cgSize size:CGSize) -> CVPixelBuffer? {
        var pixelBuffer: CVPixelBuffer?
        let attrs = [kCVPixelBufferCGImageCompatibilityKey: kCFBooleanTrue,
                     kCVPixelBufferCGBitmapContextCompatibilityKey: kCFBooleanTrue] as CFDictionary
        let width:Int = Int(size.width)
        let height:Int = Int(size.height)

        CVPixelBufferCreate(kCFAllocatorDefault,
                            width,
                            height,
                            kCVPixelFormatType_32BGRA,
                            attrs,
                            &pixelBuffer)

        // put bytes into pixelBuffer
        let context = CIContext()
        context.render(self, to: pixelBuffer!)
        return pixelBuffer
    }
}

Core MLを使ったアプリを作っています。
機械学習関連の情報を発信しています。

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