Meta Doesn’t Allow Camera Access On VR Headsets, So Here’s A Workaround

August 18, 2024 by 13 Comments

The cameras at the front of Meta’s Quest VR headsets are off-limits to developers, but developer [Michael Gschwandtner] created a workaround (Linkedin post) and shared implementation details with a VR news site.

The view isn’t a pure camera feed (it includes virtual and UI elements) but it’s a clever workaround.

The demo shows object detection via MobileNet V2, which we’ve seen used for machine vision on embedded systems like the Raspberry Pi. In this case it is running locally on the VR headset, automatically identifying objects even though the app cannot directly access the front-facing cameras to see what’s in front of it.

The workaround is conceptually simple, and leverages the headset’s ability to cast its video feed over Wi-Fi to other devices. This feature is normally used for people to share and spectate VR gameplay.

First, [Gschwandtner]’s app sets up passthrough video, which means that the camera feed from the front of the headset is used as background in VR, creating a mixed-reality environment. Then the app essentially spawns itself a Chromium browser, and casts its video feed to itself. It is this video that is used to — in a roundabout way — access what the cameras see.

The resulting view isn’t really direct from the cameras, it’s akin to snapshotting a through-the-headset view which means it contains virtual elements like the UI. Still, with passthrough turned on it is a pretty clever workaround that is contained entirely on-device.

Meta is hesitant to give developers direct access to camera views on their VR headset, and while John Carmack (former Meta consulting CTO) thinks it’s worth opening up and can be done safely, it’s not there yet.

Reverse-Engineering The AMD Secure Processor Inside The CPU

August 18, 2024 by 10 Comments

On an x86 system the BIOS is the first part of the system to become active along with the basic CPU core(s) functionality, or so things used to be until Intel introduced its Management Engine (IME) and AMD its AMD Secure Processor (AMD-SP). These are low-level, trusted execution environments, which in the case of AMD-SP involves a Cortex-A5 ARM processor that together with the Cryptographic Co-Processor (CCP) block in the CPU perform basic initialization functions that would previously have been associated with the (UEFI) BIOS like DRAM initialization, but also loading of encrypted (AGESA) firmware from external SPI Flash ROM. Only once the AMD-SP environment has run through all the initialization steps will the x86 cores be allowed to start up.

In a detailed teardown by [Specter] over at the Dayzerosec blog the AMD-SP’s elements, the used memory map  and integration into the rest of the CPU die are detailed, with a follow-up article covering the workings of the CCP. The latter is used both by the AMD-SP as well as being part of the cryptography hardware acceleration ISA offered to the OS. Where security researchers are interested in the AMD-SP (and IME) is due to the fascinating attack vectors, with the IME having been the most targeted, but AMD-SP having its own vulnerabilities, including in related modules, such as an injection attack against AMD’s Secure Encrypted Virtualization (SEV).

Although both AMD and Intel are rather proud of how these bootstrapping systems enable TPM, secure virtualization and so on, their added complexity and presence invisible to the operating system clearly come with some serious trade-offs. With neither company willing to allow a security audit, it seems it’s up to security researchers to do so forcefully.

Categorizing Steel

August 18, 2024 by 24 Comments

In the movie Conan the Barbarian, we hear a great deal about “the riddle of steel.” We are never told exactly what that riddle is, but in modern times, it might be: What’s the difference between 4150 and 1020 steel? If you’ve been around a machine shop, you’ve probably heard the AISI/SAE numbers, but if you didn’t know what they mean, [Jason Lonon] can help. The video below covers what the grade numbers mean in detail.

The four digits are actually two separate two-digit numbers. Sometimes, there will be five digits, in which case it is a two-digit number followed by a three-digit number. The first two digits tell you the actual type of steel. For example, 10 is ordinary steel, while 41 is chromium molybdenum steel. The last two or three digits indicate how much carbon is in the steel. If that number is, say, 40, then the steel contains approximately 0.40% carbon.

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A 3D-printed 8-Shaft Table Loom

Simple 3D-Printed Table Loom For Complex Weavings

August 17, 2024 by 17 Comments

The loom has been a transformative invention throughout history, shaping the textile industry from simple hand looms to complex, fully automated machines. Now, thanks to advancements in 3D printing, this age-old craft is being revitalized by modern makers. One such creator, [Fraens], has recently designed a unique 3D-printed table loom with eight shafts, offering a simpler yet innovative approach to weaving. This project is a fresh take on traditional looms, blending centuries of design knowledge with contemporary technology.

[Fraens], a longtime enthusiast of looms, has spent considerable time studying the countless designs that have evolved over more than 200 years. Drawing inspiration from these, he has crafted a more accessible version—a table loom that can be operated using levers to control the warp threads. Unlike larger, more complex looms, this 3D-printed model allows users to experiment with various weaving patterns easily, using different colors and sequences to create beautiful, intricate designs. [Fraens] provides guidance on how to adapt patterns meant for larger looms to this compact, lever-operated version on his website and in a detailed video tutorial.

This project is perfect for anyone interested in weaving or DIY technology. [Fraens]’ 3D-printed loom offers a new way to explore textile creation, making it both approachable and rewarding. To see this innovative loom in action and learn how to build your own, check out the video below.

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Retrotechtacular: Powerline Sagging And Stringing In The 1950s

August 17, 2024 by 13 Comments

While high-voltage transmission lines are probably the most visible components of the electrical grid, they’re certainly among the least appreciated. They go largely unnoticed by the general public — quick, name the power line closest to you right now — at least until a new one is proposed, causing the NIMBYs and BANANAs to come out in force. To add insult to injury, those who do notice the megastructures that make modern life possible rarely take a moment to appreciate the engineering that goes into stringing up hundreds of miles of cable and making sure it stays up.

Not so the Bonneville Power Administration, the New Deal-era federal agency formed to exploit the hydroelectric abundance of the Pacific Northwest of the United States, which produced this 1950 gem detailing the stringing and sagging of power lines. Unsurprisingly, the many projects needed to wire together the often remote dams to the widely distributed population centers in an area that was only just starting to see growth began in the BPA’s offices, where teams of engineers hunched over desks worked out the best routes. Paper, pencil, and slide rules were the tools of the trade, along with an interesting gadget called a conductor sag template, a hardware implementation of the catenary equation that allowed the “sagger” to determine the height of each tower. The conductors, either steel-cored aluminum or pure copper, were also meticulously selected based on tensile strength, expected wind and ice loading, and the electrical load the line was expected to carry.

Once the engineers had their say, the hard work of physically stringing the wires began out in the field. One suspects that the work today is much the same as it was almost eighty years ago, save for much more stringent health and safety regulations. The prowess needed to transfer the wires from lifting sheaves to the insulators is something to behold, as is the courage required to work from ladders hanging from wires at certain death heights. But to our mind, the real heroes were the logistics fellows, who determined how much wire was needed for each span and exactly where to stage the reels. It’s worth sparing a moment’s thought for the daring photographer who captured all this action, likely with little more than a leather belt and hemp rope for safety.

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Spy Tech: Making Microdots

August 17, 2024 by 17 Comments

It isn’t just a spy movie trope: secret messages often show up as microdots. [The Thought Emporium] explores the history of microdots and even made a few, which turned out to be — to quote the video you can see below — “both easier than you might think, and yet also harder in other ways.”

If you want to hide a secret message, you really have two problems. The first is actually encoding the message so only the recipient can read it. However, in many cases, you also want the existence of the message to be secret. After all, if an enemy spy sees you with a folder of encrypted documents, your cover is blown even if they don’t know what the documents say.

Today, steganography techniques let you hide messages in innocent-looking images or data files. However, for many years, microdots were the gold standard for hiding secret messages and clandestine photographs. The microdots are typically no bigger than a millimeter to make them easy to hide in plain sight.

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40,000 FPS Omega camera captures Olympic photo-finish

Olympic Sprint Decided By 40,000 FPS Photo Finish

August 17, 2024 by 55 Comments

Advanced technology played a crucial role in determining the winner of the men’s 100-meter final at the Paris 2024 Olympics. In a historically close race, American sprinter Noah Lyles narrowly edged out Jamaica’s Kishane Thompson by just five-thousandths of a second. The final decision relied on an image captured by an Omega photo finish camera that shoots an astonishing 40,000 frames per second.

This cutting-edge technology, originally reported by PetaPixel, ensured the accuracy of the result in a race where both athletes recorded a time of 9.78 seconds. If SmartThings’ shot pourer from the 2012 Olympics were still around, it could once again fulfill its intended role of celebrating US medals.

Omega, the Olympics’ official timekeeper for decades, has continually innovated to enhance performance measurement. The Omega Scan ‘O’ Vision Ultimate, the camera used for this photo finish, is a significant upgrade from its 10,000 frames per second predecessor. The new system captures four times as many frames per second and offers higher resolution, providing a detailed view of the moment each runner’s torso touches the finish line. This level of detail was crucial in determining that Lyles’ torso touched the line first, securing his gold medal.

This camera is part of Omega’s broader technological advancements for the Paris 2024 Olympics, which include advanced Computer Vision systems utilizing AI and high-definition cameras to track athletes in real-time. For a closer look at how technology decided this historic race, watch the video by Eurosport that captured the event.

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