I am not an expert on Austrian Military uniforms by any means. But this is clearly a Austro-Hungarian uniform judging from the scalloped pockets. The individual has no indication of rank on his collar. So, he was probably just a private. He is wearing the standard "general lanyard" on his left breast which was attached to his qualification badge. What is puzzling here is that the badge indicates connection to the Kreigsmarine (see the anchor). But they did not use this lanyard. A search for this badge did not yield any examples. Sorry.
CK