Welcome to WebmasterWorld Guest from 126.96.36.199
I think it won't be banned, since a ban should come from a human checker. But, will I be penalised?
<img src="/the-image.png" />
<span class="image_swap">Linked Text</span>
Or something to the above effect.
I have used something similar to the above without harming rankings, but that could change with a twist of the dial, so I would use any method of hiding text with caution.