Social media was made for sharing. Family and friends from far away can check out your wedding photos or that delicious steak you had last night. Post pictures of your trip to Bora Bora and let your loved ones live vicariously through you.
You do need to be careful about oversharing. While it’s safe to post a picture of the beachside hut you rented, you should resist the urge to post flight details or boarding passes. All that personal information (and even the barcode) invites hackers and scammers to come after you. Tap or click here to see how much damage a crook can do with just a screenshot of your boarding pass.
You may think it’s OK to share screenshots containing sensitive information as long as you mark them up with editing software. Well, it turns out that people can see through your scribbles and reveal what you’re trying to cover up.
Your photos can reveal more than you realize
It’s always good practice to keep your sensitive information hidden online. Even a seemingly-innocent screenshot could contain personal details.
The virtual equivalent of redacting information is to open the image in your iPhone’s editing app and drag a marker over the text you want to hide. On the surface, that might seem like a job well done.
But as a TikTok user recently demonstrated, that can easily be reversed. Any blacked-out image sent from one iPhone to another can be edited to reveal the details underneath.
A video posted by TikTok user lifehack.america shows how an image that was edited with the iPhone’s Markup tool can be manipulated to reveal its secrets. The video has more than 4 million views:
As you can see, part of the text message was blacked out. But by turning up the Exposure and Brilliance settings for the image, any alterations made with the editing app’s marker or pen utility fade away. And that’s all there is to it.
Here’s the right way to redact private info
It’s worth saying: If you feel the need to censor information in any photo, you should reconsider sharing it.
If you still want to send the picture, you’re better off cropping out the sensitive information. To crop an image on an iPhone:
- Open the screenshot in the Photos app.
- Tap Edit in the top right corner.
- In the bottom bar, tap the third icon, which looks like zig-zags with two arrows around it.
- Your image will now have a border around it and cropping guidelines in the corners.
- Drag each corner until just the information you want to share is in the borders.
- When you are happy with the crop, tap Done at the bottom.
But what if the text or other information you want to cut out is in the middle of the photo or screenshot? You can use the iPhone’s marker feature — but you need to be extra careful about how you use it.
Open your photo and wipe over the detail(s) you want to hide several times with the iPhone’s marker tool. Make sure you lift your finger and leave it pressed down each time you change direction. That will create several layers that eventually will be much harder to reverse with photo editing tricks.
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