How can I get a `ByteArray` from `UIImage`?

# ios

[electrolobzik]

How can I get a ByteArray from UIImage?

[Russell Stewart]

In Swift or Kotlin? This works for me in Swift:

extension UIImage {
    func toByteArray() -> KotlinByteArray? {
        if let data = self.resize(targetSize: CGSizeMake(1020, 768)).jpegData(compressionQuality: 0.8) {
            return ImageUtils().dataToByteArray(data: data)
        } else {
            return nil
        }
    }
}

[Russell Stewart]

I haven't tried it in Kotlin, but that might give you some clues at least.

[electrolobzik]

@Russell Stewart I don’t see resize method in UIImage

[electrolobzik]

and what is ImageUtils?

[electrolobzik]

I am trying to do that in Kotlin

[Russell Stewart]

Ah! Sorry, my mistake. ImageUtils is a shared object I wrote in the ios Kotlin module:

typealias ImageBytes = NSData
@OptIn(ExperimentalForeignApi::class)
fun ImageBytes.toByteArray(): ByteArray = ByteArray([e-mail]()).apply {
    usePinned {
        memcpy(it.addressOf(0), [e-mail], [e-mail])
    }
}

@Suppress("unused")
object ImageUtils {
    fun dataToByteArray(data: NSData): ByteArray {
        return data.toByteArray()
    }
}

[Russell Stewart]

I'm not sure why you aren't seeing the resize method in UIImage though.

[Russell Stewart]

Although that's not relevant to your question anyway. I just have that to resize the image for faster upload; it's not necessary for converting to a ByteArray.