Do social media filters work?

I always check privacy settings and share content I am comfortable with. However, in today's digital era, some things are embedded in our ways that it is hard to always catch yourself before posting.

Social media filters are popular because they can make you look different (I didn't say - beautiful!) or for fun. I also see parents post photos with their kids, except they put a sticker on their children's faces or some other filter in their genuine attempt to protect their child's digital footprint.

I fell in that trap, and did I panick later?

Absolutely! This is how it went.

It was my father's birthday, and I thought it would be nice to post a photo of him holding my son, his grandchild. To protect my son, I put a filter on his face as has become a common practice. I wrote what I wanted to write and pressed the "Post" button. Two days later, it dawned on me what I had done! I quickly went to remove it, but there is truth to "once on the internet, it stays on the internet." So, before I caused any drama, I wanted to understand whether my fear was justified. Spoiler: Kinda!

The theory around images and filters is beautiful but complicated. Instead of boring you with jargon and equations (based on your feedback), I will find alternative ways to explain it.

When you have two images, such as a photo and a filter like an emoji or a blur, there are multiple ways they can be combined. The simplest one is to add. That's right! Original_Photo + Filter = Photo_Filtered. That means that Photo_Filtered - Filter = Original_Photo!

Now adding is one of the simplest forms, and for those interested, there is a whole field of image convolutions and more. Regardless, it all hinges on whether the edits were made on the original photo or on top of it. I am referring to layers here. If the original photo is in layer one, and then the edits are in another layer, then the content of layer one remains discoverable.

Vecteezy

If you worked with tools like Photoshop, Procreate or something similar, where you need to create a new layer to make an edit without compromising the original, then you know what I am talking about. Those who haven't, consider placing different coloured transparent paper over a photo. This essentially involves filtering the original photo to give it a coloured tint. Instead of just colour, put a sticker on that paper, but not on the original. One might take a photo with the final edits and decide to print that, but the original is always retrievable by removing all the papers on top of the original.

By "peeling" off edits, the original can be derived.

I then decided to check what happens on Facebook. Instead of reading through its lengthy documentation (which any legal professional should do—I am not a lawyer), I decided to prompt Claude.ai.

The prompt I started the conversation with was:

"when you upload a photo on facebook and you put in an emoji on that filters, to hide a face, is the filter added, convolved or does it replace the pixels of the underlying photo"

The output indicated that the filter is added as a layer, not convolved, and does not replace the pixels in the original photo. This alarmed me, so I prompted further:

"so then you can remove the emoji to get back to the original photo in the base layer"

Anthropic Claude.ai (Sonnet 4 free user) returned the following:

Output by Claude - Anthropic.

When the layers are flattened, it should disrupt the underlying pixels to the point that removing the known filter would leave the distortion that, in theory, the original is unrecoverable. This is akin to cutting out the face from a photo, leaving no trace of what was there. Digitally, that looks different and whether the original is stored or not depends on several factors, including the company's ethical policies, as indicated by the AI.

Needless to say, I deleted the photo and promised myself to remain on alert. What starts as an honest way to share life updates securely can quickly open a backdoor for personal biometrics to slip through the web.