★ UIImage Extension リサイズメソッド
extension UIImage {
func resize(size: CGSize) -> UIImage {
let widthRatio = size.width / self.size.width
let heightRatio = size.height / self.size.height
let ratio = (widthRatio < heightRatio) ? widthRatio : heightRatio
let resizedSize = CGSize(width: (self.size.width * ratio), height: (self.size.height * ratio))
// 画質を落とさないように設定
UIGraphicsBeginImageContextWithOptions(resizedSize, false, 0.0)
drawInRect(CGRect(x: 0, y: 0, width: resizedSize.width, height: resizedSize.height))
let resizedImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return resizedImage
}
}