"Invalid input image - format must be in ['RGBA', 'LA', 'L'], got RGB." iOS Swift

Question

I am using the OpenAI "Create Image Edit" API link. My mask image is maskImage.png.

After calling the API, when the response comes, I have got the error:

Invalid input image - format must be in ['RGBA', 'LA', 'L'], got RGB."

How can I change the PNG image format as ['RGBA', 'LA', 'L'] in iOS Swift?

I have found a solution in JavaScript, How to validate an image before sending to DALL E API with front-end JavaScript. But I can not find a solution in iOS.

Answer 1

All you have to do is add opacity/alpha to the UIImage/pngData.

extension UIImage {
    var hasAlpha: Bool {
        guard let alphaInfo = self.cgImage?.alphaInfo else {return false}
        return alphaInfo != CGImageAlphaInfo.none &&
            alphaInfo != CGImageAlphaInfo.noneSkipFirst &&
            alphaInfo != CGImageAlphaInfo.noneSkipLast
    }
}

Is a quick way to check if a UIImage has alpha.

You can add alpha with

extension UIImage {

    func imageWithAlpha(alpha: CGFloat) throws -> UIImage {
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        draw(at: CGPointZero, blendMode: .normal, alpha: alpha)
        guard let newImage = UIGraphicsGetImageFromCurrentImageContext() else{
            UIGraphicsEndImageContext()
            throw ImageError.unableToAddAplhaToImage
        }
        UIGraphicsEndImageContext()
        return newImage
    }
    enum ImageError: LocalizedError{
        case unableToAddAplhaToImage
    }
}

1 being a dark image and 0 being a transparent image, OpenAI is looking for 0.

The method above will change the entire UIImage, if you use this the entire image will be replaced.

A mask will only have sections of an image that have a value of 0.

The PNG you are showing doesn't show any pixels as zero.

In short, with the code above if image.hasAlpha == false you will get the error you are talking about when you submit.

if if image.hasAlpha == true then it is ok with OpenAI.

In javascript you can use Jimp to simplify the whole thing, you can do all the checks in just a few lines.

Dall E API error: "Invalid input image - format must be in ['RGBA', 'LA', 'L'], got RGB."