Making a GIF from images using Swift (macOS)

Question

I was wondering if there was a way to convert an array of NSImages using Swift in macOS/osx?

I should be able to export it to file afterwards, so an animation of images displayed on my app would not be enough.

Thanks!

It depends on what you mean by "is there a way". There "is a way" in the sense that you can code it yourself, but I don't think that there's any API that looks like `NSGIF(imageSequence:)` in Foundation or Cocoa. — zneak, Aug 12 '16 at 18:37
I understand. Do you think I might be able to find an easy to implement library, or sample code? — Jacobo Koenig, Aug 12 '16 at 18:43
Actually, you may want to look into the [Image I/O](https://developer.apple.com/library/mac/documentation/GraphicsImaging/Reference/ImageIORefCollection/index.html#//apple_ref/doc/uid/TP40005102) framework ([example](http://stackoverflow.com/questions/14915138/create-and-and-export-an-animated-gif-via-ios)). — zneak, Aug 12 '16 at 18:47

score 7 · Accepted Answer · answered Aug 13 '16 at 17:00

Image I/O has the functionalities you need. Try this:

var images = ... // init your array of NSImage

let destinationURL = NSURL(fileURLWithPath: "/path/to/image.gif")
let destinationGIF = CGImageDestinationCreateWithURL(destinationURL, kUTTypeGIF, images.count, nil)!

// The final size of your GIF. This is an optional parameter
var rect = NSMakeRect(0, 0, 350, 250)

// This dictionary controls the delay between frames
// If you don't specify this, CGImage will apply a default delay
let properties = [
    (kCGImagePropertyGIFDictionary as String): [(kCGImagePropertyGIFDelayTime as String): 1.0/16.0]
]


for img in images {
    // Convert an NSImage to CGImage, fitting within the specified rect
    // You can replace `&rect` with nil
    let cgImage = img.CGImageForProposedRect(&rect, context: nil, hints: nil)!

    // Add the frame to the GIF image
    // You can replace `properties` with nil
    CGImageDestinationAddImage(destinationGIF, cgImage, properties)
}

// Write the GIF file to disk
CGImageDestinationFinalize(destinationGIF)

Making a GIF from images using Swift (macOS)

1 Answers1