extension UIImage {
func compressImage(maxLength: Int) -> UIImage {
let tempMaxLength: Int = maxLength / 8
var compression: CGFloat = 1
guard var data = self.jpegData(compressionQuality: compression), data.count > tempMaxLength else { return self }
var max: CGFloat = 1
var min: CGFloat = 0
for _ in 0..<6 {
compression = (max + min) / 2
data = self.jpegData(compressionQuality: compression)!
if CGFloat(data.count) < CGFloat(tempMaxLength) * 0.9 {
min = compression
} else if data.count > tempMaxLength {
max = compression
} else {
break
}
}
var resultImage: UIImage = UIImage(data: data)!
if data.count < tempMaxLength { return resultImage }
var lastDataLength: Int = 0
while data.count > tempMaxLength && data.count != lastDataLength {
lastDataLength = data.count
let ratio: CGFloat = CGFloat(tempMaxLength) / CGFloat(data.count)
print("Ratio =", ratio)
let size: CGSize = CGSize(width: Int(resultImage.size.width * sqrt(ratio)),
height: Int(resultImage.size.height * sqrt(ratio)))
UIGraphicsBeginImageContext(size)
resultImage.draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
resultImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
data = resultImage.jpegData(compressionQuality: compression)!
}
return resultImage
}
}