Xcode 12.3 , Swift 5.3 NSImage to base64

Question

I'm trying to find a way on macOS, Swift to convert a NSImage that comes from a Image View and to convert it to base64 so I can send it via string to another app.

So far I found some here,

Apparently in Swift 4

extension NSImage {
var base64String: String? {
    guard let rep = NSBitmapImageRep(
        bitmapDataPlanes: nil,
        pixelsWide: Int(size.width),
        pixelsHigh: Int(size.height),
        bitsPerSample: 8,
        samplesPerPixel: 4,

        hasAlpha: true,
        isPlanar: false,
        colorSpaceName: .calibratedRGB,
        bytesPerRow: 0,
        bitsPerPixel: 0
        ) else {
            print("Couldn't create bitmap representation")
            return nil
    }

    NSGraphicsContext.saveGraphicsState()
    NSGraphicsContext.current = NSGraphicsContext(bitmapImageRep: rep)
    draw(at: NSZeroPoint, from: NSZeroRect, operation: .sourceOver, fraction: 1.0)
    NSGraphicsContext.restoreGraphicsState()

    guard let data = rep.representation(using: NSBitmapImageRep.FileType.png, properties: [NSBitmapImageRep.PropertyKey.compressionFactor: 1.0]) else {
        print("Couldn't create PNG")
        return nil
    }

    // With prefix
    // return "data:image/png;base64,(data.base64EncodedString(options: []))" 
    // Without prefix
    return data.base64EncodedString(options: []))
} }

But the problem is that while I get the image it is super small, and enlarging it in the other app creates a super pixelated app.

In my source app the image based on the representation debug info is a 150 x 200 picture ,but via the code above it comes a 30 x 40 image I guess. any idea how to have this working ?

based on the debug data I have the following :

Optional("<NSImage 0x600003301180 Size={33.600000000000001, 48} Reps=(
    "NSBitmapImageRep 0x600002606940 Size={33.600000000000001, 48} ColorSpace=Generic Gray Gamma 2.2 Profile colorspace BPS=8 BPP=8 Pixels=140x200 Alpha=NO Planar=NO Format=0 CurrentBacking=<CGImageRef: 0x10061d900> CGImageSource=0x60000025d6a0"
)>")

so what should I set in my case to have it right ?

Thanks in advance

question from:https://stackoverflow.com/questions/65882292/xcode-12-3-swift-5-3-nsimage-to-base64

Answer 1

Waitting for answers