If you're looking for a counterpart to manually, you could consider optically – but I think that word would be even less suitable in this case.
I have no problem with the word manually used in the context you describe. We do a lot of video editing where I work, and, yes, the process can be very time consuming and labor intensive. It may not be manual labor in the same sense that landscaping or auto assembly would be, but it could be construed as manual labor in the same sense that secretarial work might be – after all, we're paying someone to do it.
Furthermore, most video scanning does involve use the hands to a certain extent, even if it's only using a keyboard and mouse, or the controllers on a video player.
Incidentally, Wikipedia's article on manual labor has some interesting points about the increasingly blurry lines between skilled and manual labor due to the advent of technology. It's worth reading more than a short excerpt, but I'll give this teaser [emphasis added]:
Automation helps to bring mechanisation to more complicated tasks that require finer dexterity, decision making based on visual input, and a wider variety of intelligent movements.
Borrowing from that thought, you could say that your product helps expedite or facilitate the complicated and time-consuming process of video editing. From NOAD:
facilitate: make (an action or process) easy or easier
expedite: make (an action or process) happen sooner or be accomplished more quickly
By the way, isn't it interesting how the root of expedite is ped (meaning foot), yet we have no problem applying that word to processes that don't necessarily involve on-foot activities?