I used to live at Lake Nacimiento in Ca, one of the top spotted bass fisheries in the state, and have caught plenty of each from it.
That photo makes it difficult to ID that fish, in fact the only thing that is might identify it a spotty is the Ventral striping.
Quick way to identify them is to check the tongue for a tooth patch, they have one similar to smallmouths.
Large mouth don't have it.
The jaw length is also shorter than a largemouth and doesn't extend past the back edge of the eye.
Other than that they are so similar it pretty much takes an expert to tell the difference.