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Created October 23, 2019 18:38
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import UIKit
extension UIImage {
func resize(to newSize: CGSize) -> UIImage? {
guard self.size != newSize else { return self }
UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0)
self.draw(in: CGRect(x: 0, y: 0, width: newSize.width, height: newSize.height))
defer { UIGraphicsEndImageContext() }
return UIGraphicsGetImageFromCurrentImageContext()
func pixelBuffer() -> CVPixelBuffer? {
let width = Int(self.size.width)
let height = Int(self.size.height)
let attrs = [kCVPixelBufferCGImageCompatibilityKey: kCFBooleanTrue, kCVPixelBufferCGBitmapContextCompatibilityKey: kCFBooleanTrue] as CFDictionary
var pixelBuffer: CVPixelBuffer?
let status = CVPixelBufferCreate(kCFAllocatorDefault, width, height, kCVPixelFormatType_32ARGB, attrs, &pixelBuffer)
guard status == kCVReturnSuccess else {
return nil
CVPixelBufferLockBaseAddress(pixelBuffer!, CVPixelBufferLockFlags(rawValue: 0))
let pixelData = CVPixelBufferGetBaseAddress(pixelBuffer!)
let rgbColorSpace = CGColorSpaceCreateDeviceRGB()
guard let context = CGContext(data: pixelData, width: width, height: height, bitsPerComponent: 8, bytesPerRow: CVPixelBufferGetBytesPerRow(pixelBuffer!), space: rgbColorSpace, bitmapInfo: CGImageAlphaInfo.noneSkipFirst.rawValue) else {
return nil
context.translateBy(x: 0, y: CGFloat(height))
context.scaleBy(x: 1.0, y: -1.0)
self.draw(in: CGRect(x: 0, y: 0, width: width, height: height))
CVPixelBufferUnlockBaseAddress(pixelBuffer!, CVPixelBufferLockFlags(rawValue: 0))
return pixelBuffer
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