Captura/Core Extensions/CGImage+resize.swift


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import CoreGraphics

extension CGImage {
  func resize(by scale: CGFloat) -> CGImage? {
    let width = Int(CGFloat(self.width) / scale)
    let height = Int(CGFloat(self.height) / scale)
    
    let bitsPerComponent = self.bitsPerComponent
    let colorSpace = self.colorSpace ?? CGColorSpace(name: CGColorSpace.sRGB)!
    let bitmapInfo = self.bitmapInfo.rawValue
    
    guard let context = CGContext(data: nil, width: width, height: height, bitsPerComponent: bitsPerComponent, bytesPerRow: 0, space: colorSpace, bitmapInfo: bitmapInfo) else {
        return nil
    }
    
    context.interpolationQuality = .high
    context.draw(self, in: CGRect(x: 0, y: 0, width: width, height: height))
    
    return context.makeImage()
  }
}