Photographic images that take on a painterly or near-abstract look generally fall more into a fine art category than a stock image category.
For many decades, photography was not taken seriously as an art form. Galleries generally dismissed it, because it was representational rather than abstract. More recently, however, there has been a greater acceptance of photography as fine art.
Part of this paradigm shift may be due to, in past years, manipulation of the image in the darkroom into something other than representational. Today, we have Photoshop® and a host of plugins that allow us to easily coerce a photographic image into becoming a painting (albeit, never an original), or, if taken further, a complete abstract.
I’m no exception when it comes to software manipulation of images. In my “Abstract & Painterly” gallery on Photoshelter (see first image below-click on it if you don’t see a slideshow), examples of this can be found. Similarly, the “Altered States” gallery (see second image below) involves image tweaking. These same images and more are also available on my Fine Art America site.