Removing lens dirt spots from footage

Hi team, I recently shot some video footage on my iPhone 5 only to discover during the editing process in Final Cut Pro X a small, dirt spot, which not large, it is rather irritating in certain shots. Are there any free plug-ins for Final Cut X that people have used? I have tried the video footage in Photoshop 6 using the Spot Healing Tool, and whilst that works, it is very tedious as I have to apply the correction frame by frame. I have seen some plug ins where they can create a mask around the offending spot that appear much quicker. Any tips and suggestions would be most welcome. If you look at the attached screen-shot, you will notice a small spot roughly in the centre of the screen....

Not for free, but SliceX has a rotoscope plugin that is awesome, and super worth the $99 price tag.

Thanks Ben for your suggestion. I have downloaded the trial version and will try over the next 2 weeks. From what I have seen with similar tools, these tend to work when the camera is still and fixed on the same spot, and require a lot more work, naturally, when the footage is from a hand-held, and in my case, shot with an iPhone 5. Stay tuned

Shaky footage should be stabilized first, then apply effects. Just a tip.

Thanks Ben, but I have already applied stabilisation. Must be my shaky hands as I am getting older

It turns out the dirt is inside the camera lens, and apparently this is a common problem with a lot of iPhone 5 users; they have reported the exact same problem, so now I am off to the Apple store for repairs. BTW - I tried the SliceX trial version, and in most parts I have success. It is a tedious process, and I guess for critical, paid work, where there is no other footage, this would be a great tool to salvage the project, and the pride of the cameraman.