The idea is a wooden box hung on the wall that folds up when not in use. [Alex] starts with Baltic birch plywood cut into the panels. Next, he applies edge banding (a thin veneer with some glue on the backside) so that all the exposed edges look like natural wood. Next, a screen hole is routed into the face frame, allowing an LCD monitor to sit snuggly in. A combination of pocket holes and biscuits allows [Alex] to assemble everything with no visible screws or fasteners.
With the help of a 3D printer, he quickly fabricated a locking mechanism to keep the front panel attached when it folds up. The hinge is also 3D printed. The typical Raspberry Pi 4 powers this particular machine. Two french cleats hold the box onto the wall, and once the system is on the wall, we have to say it looks incredible.
One of the core lessons any physics student will come to realize is that the more you know about physics, the less intuitive it seems. Take the nature of light, for example. Is it a wave? A particle? Both? Neither? Whatever the answer to the question, scientists are at least able to exploit some of its characteristics, like its ability to bend and bounce off of obstacles. This camera, for example, is able to image a room without a direct light-of-sight as a result.
The process works by pointing a camera through an opening in the room and then strobing a laser at the exposed wall. The laser light bounces off of the wall, into the room, off of the objects on the hidden side of the room, and then back to the camera. This concept isn’t new, but the interesting thing that this group has done is lift the curtain on the image processing underpinnings. Before, the process required a research team and often the backing of the university, but this project shows off the technique using just a few lines of code.
This project’s page documents everything extensively, including all of the algorithms used for reconstructing an image of the room. And by the way, it’s not a simple 2D image, but a 3D model that the camera can capture. So there should be some good information for anyone working in the 3D modeling world as well.
What is suspicious about the books in the image above? Is it that there is no bookend? How about the radio waves pouring out of them? [Clay Weiland] does not like the way a bare router looks in the living room, but he appreciates the coverage gained by putting it in the middle of his house. He added a layer of home decorating camouflage in the form of some second-hand book covers to hide the unsightly bit of tech.
There isn’t a blog post or video about this particular build anywhere. The photos were submitted to our tip line as-is with the note that a table-saw is involved. We can safely infer that book covers are stripped of their pages and filled with wooden blanks painted white and stuck together to look like a cluster of literature. The takeaway from this example is that our tech does not have to be hidden away like a secret, or disrupt the decor, it can be placed as functionally as possible without sacrificing Feng Shui.
Getting bounced to a website by scanning a QR code is no longer an exciting feat of technology, but what if you scanned the ingredient list on your granola bar and it went to the company’s page for that specific flavor, sans the matrix code?
Bright minds at the Columbia University in the City of New York have “perturbed” ordinary font characters so the average human eye won’t pick up the changes. Even ordinary OCR won’t miss a beat when it looks at a passage with a hidden message. After all, these “perturbed” glyphs are like a perfectly legible character viewed through a drop of water. When a camera is looking for these secret messages, those minor tweaks speak volumes.
The system is diabolically simple. Each character can be distorted according to an algorithm and a second variable. Changing that second variable is like twisting a distorted lens, or a water drop but the afterimage can be decoded and the variable extracted. This kind of encoding can survive a trip to the printer, unlike a purely digital hidden message.
Hidden messages like these are not limited to passing notes, metadata can be attached to any text and extracted when necessary. Literature could include notes without taking up page space so teachers could include helpful notes and a cell phone could be like an x-ray machine to see what the teacher wants to show. For example, you could define what “crypto” actually means.
You can see the covert mode of the Pi Palette below. It resembles a clamshell cosmetics case with the makeup and applicator in the base and a mirror on the underside of the flip-up lid. The mirror hides an LCD screen in the portrait orientation, as well as a Raspberry Pi 3 running Kali Linux.
The base of the case includes a portable battery beneath the wireless keyboard/touchpad — both of which are revealed when the cosmetics tray is removed. An inductive charger is connected to the battery and [Naomi] built a base station which the Pi Palette sits in for wireless charging.
She envisions this as a covert penetration testing. For that, the Pi Palette needs the ability to put the WiFi dongle into promiscuous mode. She wired in a dual dip-switch package and really went the extra mile to design it into the case. The fit and finish of that switch is just one tiny detail the illustrates the care taken with the entire project. With such a beautiful final project it’s no wonder she took to the streets to show it off. Check that out, as well as the build process, in the video after the break.
Once activated, you’ll be able to plug into the USB port and download the album, or sit there on a remote hillside cliff overlooking the ocean and enjoy the new tunes. Because there’s a headphone jack in the rock, naturally. Besides being a cool hack, we think that putting people in the right physical and mental space for a serious listening is brilliant. Watch the video embedded below for an idea of the making of and a view from the site.
Some might be screaming at their screens right now… this is how modern horror films start and before you know it the undead are lurking behind you waiting to strike. Seasonal thrills aside, this is turning into an involved community effort to solve the puzzle. [Johny] published the video and posted a thread on reddit.
This has all the hallmarks of a good time. The audio spectrogram shows hidden data embedded in the file — a technique known as steganography. There are some real contortions to make meaning from this. When you’re looking for a solution any little hit of a pattern feels like you’ve found something. But searching for the decrypted string yields a YouTube video with the same name; we wonder if they’ve tried to recover steganographic data from that source?
[Johny] mentions that this parcel was unsolicited and that people have suggested it’s a threat or something non-sensical in its entirety. We’re hoping it’s a publicity stunt and we’re all disappointed in the end, because solving the thing is the best part and publicity wouldn’t work if there was no solution.
The bright minds of the Hackaday community should be the ones who actually solve this. So get to work and let us know what you figure out!