let width = UInt32(512)
let height = UInt32(512)

var imageData: [UInt32] = .init(repeating: 0, count: Int(width * height))

var index = 0
for y: UInt32 in 0 ..< height {
    for x: UInt32 in 0 ..< width {
        let r: UInt32 = y & 0xFF
        let g: UInt32 = x & 0xFF
        let b: UInt32 = (0xFF - x & 0xFF)

        imageData[index] = (r << 16) + (g << 8) + (b << 0)

        index += 1
    }
}

let encoder = MicroPNG()

let pngData = try! encoder.encodeRGBUncompressed(data: imageData,
                                                 width: width,
                                                 height: height)

pngData.withUnsafeBytes { pointer in
    let data = Data(bytes: pointer.baseAddress!, count: pointer.count)

    try! data.write(to: URL(fileURLWithPath: "EXPORT PATH"))
}