private GifDrawableTransformation[] toGifTransformations(Transformation<Bitmap>[] bitmapTransformations) {
        GifDrawableTransformation[] transformations = new GifDrawableTransformation[bitmapTransformations.length];
        for (int i = 0; i < bitmapTransformations.length; i++) {
            transformations[i] = new GifDrawableTransformation(bitmapTransformations[i], glide.getBitmapPool());
        }
        return transformations;
    }
Transforms each frame of the GIF using the given transformations.

@see #fitCenter()
@see #centerCrop()
@see #transformFrame(BitmapTransformation...)
@see #transform(Transformation[])

@param bitmapTransformations The transformations to apply in order to each frame.
@return This request builder.
core/src/main/java/com/bumptech/glide/GifRequestBuilder.java