How to fit content of GIF animation in View and in live wallpaper?

Background

I have a small live wallpaper app, that I want to add support for it to show GIF animations.
For this, I've found various solutions. There is the solution of showing a GIF animation in a view (here), and there is even a solution for showing it in a live wallpaper (here).
However, for both of them, I can't find how to fit the content of the GIF animation nicely in the space it has, meaning any of the following:

1. center-crop
2. stretch to fit width/height
3. set as original size, centered, and stretch to fit width/height only if too large.

The problem

None of those is actually about ImageView, so I can't just use the scaleType attribute.

What I've found

There is a solution that gives you a GifDrawable (here), which you can use in ImageView, but it seems it's pretty slow in some cases, and I can't figure out how to use it in LiveWallpaper and then fit it.
The main code of the LiveWallpaper GIF handling is as such (here) :

class GIFWallpaperService : WallpaperService() {
    override fun onCreateEngine(): WallpaperService.Engine {
        val movie = Movie.decodeStream(resources.openRawResource(R.raw.cinemagraphs))
        return GIFWallpaperEngine(movie)
    }

    private inner class GIFWallpaperEngine(private val movie: Movie) : WallpaperService.Engine() {
        private val frameDuration = 20

        private var holder: SurfaceHolder? = null
        private var visible: Boolean = false
        private val handler: Handler = Handler()
        private val drawGIF = Runnable { draw() }

        private fun draw() {
            if (visible) {
                val canvas = holder!!.lockCanvas()
                canvas.save()
                canvas.scale(3f, 3f)
                movie.draw(canvas, -100f, 0f)
                canvas.restore()
                holder!!.unlockCanvasAndPost(canvas)
                movie.setTime((System.currentTimeMillis() % movie.duration()).toInt())

                handler.removeCallbacks(drawGIF)
                handler.postDelayed(drawGIF, frameDuration.toLong())
            }
        }

        override fun onVisibilityChanged(visible: Boolean) {
            this.visible = visible
            if (visible)
                handler.post(drawGIF)
            else
                handler.removeCallbacks(drawGIF)
        }

        override fun onDestroy() {
            super.onDestroy()
            handler.removeCallbacks(drawGIF)
        }

        override fun onCreate(surfaceHolder: SurfaceHolder) {
            super.onCreate(surfaceHolder)
            this.holder = surfaceHolder
        }
    }
}

The main code for handling GIF animation in a view is as such:

class CustomGifView @JvmOverloads constructor(context: Context, attrs:
 AttributeSet? = null, defStyleAttr: Int = 0) : View(context, attrs, defStyleAttr) {
    private var gifMovie: Movie? = null
    var movieWidth: Int = 0
    var movieHeight: Int = 0
    var movieDuration: Long = 0
    var mMovieStart: Long = 0

    init {
        isFocusable = true
        val gifInputStream = context.resources.openRawResource(R.raw.test)

        gifMovie = Movie.decodeStream(gifInputStream)
        movieWidth = gifMovie!!.width()
        movieHeight = gifMovie!!.height()
        movieDuration = gifMovie!!.duration().toLong()
    }

    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        setMeasuredDimension(movieWidth, movieHeight)
    }

    override fun onDraw(canvas: Canvas) {

        val now = android.os.SystemClock.uptimeMillis()
        if (mMovieStart == 0L) {   // first time
            mMovieStart = now
        }
        if (gifMovie != null) {
            var dur = gifMovie!!.duration()
            if (dur == 0) {
                dur = 1000
            }
            val relTime = ((now - mMovieStart) % dur).toInt()
            gifMovie!!.setTime(relTime)
            gifMovie!!.draw(canvas, 0f, 0f)
            invalidate()
        }
    }
}

The questions

1. Given a GIF animation, how can I scale it in each of the above ways?
2. Is it possible to have a single solution for both cases?
3. Is it possible to use GifDrawable library (or any other drawable for the matter) for the live wallpaper, instead of the Movie class? If so, how?

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