How to check if a uiimage is blank? (empty, transparent)

Question

which is the best way to check whether a UIImage is blank?
I have this painting editor which returns a UIImage; I don\'t want to save this imag

Answer 1

Here's a solution in Swift that does not require any additional frameworks.

Thanks to answers in a related question here: Get Pixel Data of ImageView from coordinates of touch screen on xcode?

func imageIsEmpty(_ image: UIImage) -> Bool {
    guard let cgImage = image.cgImage,
          let dataProvider = cgImage.dataProvider else
    {
        return true
    }

    let pixelData = dataProvider.data
    let data: UnsafePointer = CFDataGetBytePtr(pixelData)
    let imageWidth = Int(image.size.width)
    let imageHeight = Int(image.size.height)
    for x in 0..