This Photo Gremlin Zapper Leaves Behind Gremlins Of Its Own [Review]

Can Inpaint4 remove this guy from Stonehenge?
Can Inpaint4 remove this guy from Stonehenge?

Inpaint4 is an image editor for OS X, available for $10 from the Mac App Store. It’s designed for a specific task – removing unwanted visual elements from photos. That tourist who walked through the background of your snapshot, that hanging camera strap that spoiled an otherwise good image, or that weird bit of junk you just want to take out of shot. Unfortunately it is let down too often by unreliable results.

You wouldn’t realize it simply by looking at Inpaint4’s App Store page, because the screenshots don’t show it: but this is a Windows app re-purposed for OS X. That means it looks distinctly odd on your screen, an invader from another world. But looks aren’t everything. How, you ask, does it work?</>

The workflow is simple enough. Open an image and use the marker pen tool to blot out the object or person you wish to remove. Don’t click the start button yet – pay close attention to the rectangular selection tool that appears around the area you’ve blotted out.

The app uses image data from whatever’s inside this rectangular selection to replace the thing you want to remove. So it pays to ensure that the rectangle only includes background material you wish to keep.

There’s also another tool called Guidelines. Draw these on your image to help Inpaint4 tell the difference between certain selection areas.

The results are mixed, and certainly not always perfect. Here are some examples.

I forgot the guy's shadow. My bad. There is an undo.
Now you see it... now you don't
Fencing is hard to deal with

As you can see, the tourist at Stonehenge was removed fairly well, as was the football from the swimming pool.

The third example, though, proved to be more difficult. No matter how I arranged the background selection rectangle, Inpaint4 couldn’t replace the woman on the phone with any kind of background that blended in well. Perhaps the fence is too complicated a pattern to deal with.

Using the app isn’t complicated, but one frustration is the slider that controls the marker pen’s width. As you slide it from one side to the other, there’s no visual feedback to show you what you’re doing. The result is a painful process of slide a bit, move the pointer back to the image to see how wide the marker pen is, then return to the slider and try again, and again, and again. It’s maddening.

The best result I got was in the Stonehenge image. You can see that Inpaint4 copes well with simpler backgrounds like green grass and blue sky. But that was the best result, and I don’t think it’s good enough for me to make much use of. I wouldn’t want to make prints from that image, for example.

Let’s have one more try.

... and after.

The trouble here is that to get even vaguely decent results, you have to consider your source images very carefully indeed, and that shouldn’t be the point. The results you get are far too unpredictable to justify the price you pay.

Pro: It tries hard.

Con: Unpredictable, unusable results. Windows-like UI.