iOS Swift UIImage subscript extension to get pixel color

UIImage+PixelColor.swift

import UIKit

extension UIImage {
    subscript (x: Int, y: Int) -> UIColor? {
        guard x >= 0 && x < Int(size.width) && y >= 0 && y < Int(size.height),
            let cgImage = cgImage,
            let provider = cgImage.dataProvider,
            let providerData = provider.data,
            let data = CFDataGetBytePtr(providerData) else {
            return nil
        }

        let numberOfComponents = 4
        let pixelData = ((Int(size.width) * y) + x) * numberOfComponents

        let r = CGFloat(data[pixelData]) / 255.0
        let g = CGFloat(data[pixelData + 1]) / 255.0
        let b = CGFloat(data[pixelData + 2]) / 255.0
        let a = CGFloat(data[pixelData + 3]) / 255.0

        return UIColor(red: r, green: g, blue: b, alpha: a)
    }
}

@herbgarlow sure, something like this:

let image = UIImage(named: "someimage")!
if let color = image[100, 100] {
    var red: CGFloat = 0.0
    var green: CGFloat = 0.0
    var blue: CGFloat = 0.0
    var alpha: CGFloat = 0.0
    color.getRed(&red, green: &green, blue: &blue, alpha: &alpha)

    // Do something with the color
}

Remember the subscript returns an optional incase you gave an out of bounds x or y value

can this code show the color of the pixel of a image? For example, I have uiImage, and I would like to know the color of the pixel located in [100.100], how to operate?

This code won't work if image is stored in BGR format.

Why are you copying your data? You can get the byte pointer directly from the provider.

Ive got these errors. whats wrong?

I haven’t looked at this code in awhile but looks like it needs a guard statement, I can update a lil later today

…

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On Jul 3, 2019, at 08:10, Leroy ***@***.***> wrote: Ive got these errors. whats wrong? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

I want to extract RGB values for all pixels from a frame captured during ARSession. The CVPixelBufferFormat for that is of type kCVPixelFormatType_420YpCbCr8BiPlanarFullRange. Will this code work for this format type as well?
I am new to Swift, I am having a tough time trying to understand the format types and difference in manipulating them.

Doesn't work on black for some reason