In Django, when I use:
{{ request.build_absolute_uri }}{% static \"img/myimage.jpg\" %}
It produces: \'http://myurl.com//static/img/myimage
The request object is available within your templates and you can easily access attributes such as request.scheme or request.META.HTTP_HOST to construct your base URL that you can prepend ahead of your static URL to get the full URL.
request
request.scheme
request.META.HTTP_HOST
Final example would look something like this: