Is it possible to upload images to instagram without using proprietary software or "SaaS"?

Question

I'm asking because some people are trying to convince me to upload my photos there…

Is there a way to upload images to instagram while using only free (as in free speech) software which runs locally (not a remote service; except the instagram servers themselves, of course)?

Normally it's easy to upload something; just use the browser and be done, but with Instagram it seems they intentionally made it hard to upload anything except photos made by a mobile phone and via their own proprietary application.

BTW, it's perfectly fine if the application has only a command line interface. In fact I'd prefer this.
A library for a programming language would be good too, it doesn't have to be a full blown application.

So far I only found "gramblr" but it's proprietary.

I'm looking for solutions for any systems, if it doesn't work on my OS, I'll just fix or rewrite it myself.

Answer 1

It seems now they implemented image uploading from the website (only in the "mobile" version of the website, but it's pretty obvious how to make your desktop web browser pretend it's on a mobile device). So, until they decide to take that back, it's the most realistic solution so far.

I am not 100% sure if it works, though, because when I tried to upload a picture that way, I was immediately asked to receive an SMS to a phone number, and that was asking too much, so I decided that Instagram is not worth using. In theory this might be just a honeypot to collect users' phone numbers.