DIY Camera Stabilizer Takes The Shakes Out Of Filming

We’ve all prematurely stopped watching some Youtube video because of shaky camera work that makes the video unwatchable. There is a solution available for this problem, it’s a device called a camera stabilizer and it is designed to compensate for jerky camera movement. There are several types available for purchase but they can get fairly expensive. Even the cheaper ones at a few hundred dollars are not economical for hobbyists. [John] set out to make his own camera stabilizer using some unorthodox parts.

[John’s] chose a gimble style design that effectively lowers the camera’s center of gravity down close to the camera persons hand. The handle of the device must also be mounted in a manor to prevent angular and rotation movement of the supporting hand from transferring to the camera.

The handle is from a cement trowel, on top of which is a ball bearing mounted to a threaded rod. A PVC fitting was heated to soften it and the bushing pressed in. This bearing is responsible for allowing the rotational freedom between the handle and the camera. To decouple any angular movements, two hinges were attached to the PVC fitting. The hinges are perpendicular to each other, one allows forward-back tilting while the other allows left-right tilting. The upper hinge is attached to a piece of poplar wood that also serves as a base for the camera.

At this point, if you were to try to hold this contraption with the camera installed, it would immediately tip over due to gravity. To prevent this, the center of gravity of the moving parts (including the camera) must be lowered. [John] did this by using some aluminum tubing to support wood weights that reside lower than the pivot points created by the hinges.

If you like the DIYer-style stabilizers, check this other wooded one out. Want something more polished looking? How about this pistol grip stabilizer?

RGB Video Input Hack is a Master Hack for CRT Televisions

What’s shown on the screen above is about half-way through the process of hacking RGB video into a CRT television that’s not supposed to have it. The lettering is acting a bit like a layer mask, showing bits of the Super Mario Bros. start screen which is being injected from an original Famicom. [Michael J. Moffitt] figured out that he could patch his signals into the multiplexer which is responsible for overlaying the TV’s menu system. Obviously you can’t get your Mario on with this view, but the next step was as simple as finding the blanking pin and tying it 5V. Brilliant.

This particular hack is worthy of recognition. But read through [Michael’s] write up and it’s obvious that he knows the driver circuitry beyond the realm of normal curiosity. If you ever get stuck while trying to do something custom, we’d recommend pinging him with your questions (sorry [Michael] but with great knowledge comes great responsibility).


Hacklet 15 – Arcade Fire


This week’s Hacklet is dedicated to arcade games. The arcade parlors of the 80’s and early 90’s may have given way to today’s consoles and PC games, but the classic stand-up arcade cabinet lives on! Plenty of hackers have restored old arcade cabinets, or even built their own. We’re going to take a look at some of the best arcade game-related hacks on!

blackvortex[Brayden] starts things off with his Raspberry Pi Vintage Arcade. The Black Vortex is a tabletop arcade cabinet using a Raspberry Pi, an old monitor, and some nice carpentry skills. Black Vortex uses a Raspberry Pi B+. The extra GPIO pins make interfacing buttons and joystick switches easy. On the software side, [Brayden] is using the popular PiMame (now PiPlay) flavor of Linux built for gaming and emulation. Black Vortex’s shell is plywood. [Brayden] used a pocket hole jig to build a sturdy, cabinet without extra support blocks. A stain finish really works on this one!

custom-crtNext up, [fredkono] blows our minds with the Arcade XY Monitor From Scratch. [fredkono] repairs classic Atari vector game PCBs. He needed a test monitor for his lab. The original Amplifone and WG6100 color XY monitors used in games like Tempest and Star Wars are becoming rather rare. Not a problem, as [fredkono] is building his own. Much like the WG6100, [fredkono] started with a standard color TV CRT. He removed and rewound the yoke for vector operation. The TV’s electronics were replaced with [fredkono’s] own deflection amplifier PCBs.  [fredkono] was sure to include the all- important spot killer circuit, which shuts down the electron guns before a spot can burn-in the CRT.

controlpanel[Rhys] keeps things rolling with a pair of projects dedicated to arcade controls. His TI Launchpad Arcade Control to USB Interface contains instructions and code to use a Texas Instruments Tiva C launchpad as a USB interface for arcade controls. [Rhys] puts all that to good use in his Arcade Control Panel. The control panel features MAME buttons, as well as the standard 2 player fighting game button layout. He finished off his panel with some slick graphics featuring red and blue dragons.

trongame[Sarah and Raymond] hosted a Tron:Legacy release party back in 2010. An epic arcade movie calls for an epic arcade game, or in this case, games. 16 table top arcades to be exact. All 16 machines were built in just 6 days. 8 of the machines ran Armegatron Advanced, a networked version of the classic Tron lightcycle game. The others ran a mix of classic games like PacMan or modern bullet hell shooters like Tou-Hou. The cabinets were built from expanded PVC with wood blocks as a support structure. [Sarah and Raymond] custom painted each cabinet with UV black light paint. We love the custom artwork on their personal signature machines!

mikesArcade[Mike] takes us back to the 80’s with Just Another Arcade Machine. Under the hood, this machine uses the standard Raspberry Pi and PiMame (now PiPlay) suite. [Mike] even added a trackball so he could play Centipede. What makes this arcade special is the cabinet. [Mike] found an old wardrobe with that perfect 80’s style metallic strip cladding. [Mike] removed the cladding, and cut up the chipboard frame. He re-assembled things into a stand-up arcade cabinet that looks like it came right out of Sears’ Electronics department in 1985.

Ok folks, that’s it for another episode of The Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of!

Open Source Marker Recognition for Augmented Reality


[Bharath] recently uploaded the source code for an OpenCV based pattern recognition platform that can be used for Augmented Reality, or even robots. It was built with C++ and utilized the OpenCV library to translate marker notations within a single frame.

The program started out by focusing in on one object at a time. This method was chosen to eliminate the creation of additional arrays that contained information of all of the blobs inside the image; which could cause some problems.

Although this implementation did not track marker information through multiple frames, it did provide a nice foundation for integrating pattern recognition into computer systems. The tutorial was straightforward and easy to ready. The entire program and source code can be found on Github which comes with a ZERO license so that anyone can use it. A video of the program comes up after the break:

Continue reading “Open Source Marker Recognition for Augmented Reality”

A MIPI DSI Display Shield/HDMI Adapter

MIPI DSI shield

[Tomasz] tipped us about the well documented MIPI DSI Display Shield / HDMI Adapter he put on The Display Serial Interface (DSI) is a high speed packet-based interface for delivering video data to recent LCD/OLED displays. It uses several differential data lanes which frequencies may reach 1 GHz depending on the resolution and frame rate required.

The board explained in the above diagram therefore allows any HDMI content to be played on the DSI-enabled scrap displays you may have lying around. It includes a 32MB DDR memory which serves as a frame buffer, so your “slow” Arduino platform may have enough time to upload the picture you want to display.

The CP2103 does the USB to UART conversion, allowing your computer to configure the display adapter internal settings. The platform is based around the XC6SLX9 Spartan-6 FPGA and all the source code may be downloaded from the official GitHub repository, along with the schematics and gerbers. After the break we’ve embedded a demonstration video in which a Raspi drives an iPhone 4 LCD.

Continue reading “A MIPI DSI Display Shield/HDMI Adapter”

Open Source GPU Released


Nearly a year ago, an extremely interesting project hit Kickstarter: an open source GPU, written for an FPGA. For reasons that are obvious in retrospect, the GPL-GPU Kickstarter was not funded, but that doesn’t mean these developers don’t believe in what they’re doing. The first version of this open source graphics processor has now been released, giving anyone with an interest a look at what a late-90s era GPU looks like on the inside, If you’re cool enough, there’s also enough supporting documentation to build your own.

A quick note for the PC Master Race: this thing might run Quake eventually. It’s not a powerhouse. That said, [Bunnie] had a hard time finding an open source GPU for the Novena laptop, and the drivers for the VideoCore IV in the Raspi have only recently been open sourced. A completely open GPU simply doesn’t exist, and short of a few very, very limited thesis projects there hasn’t been anything like this before.

Right now, the GPL-GPU has 3D graphics acceleration working with VGA on a PCI bus. The plan is to update this late-90s setup to interfaces that make a little more sense, and add DVI and HDMI output. Not bad for a failed Kickstarter, right?

Hacking VGA for Trippy Video Effects


Ever since flat panel LCD monitors came on the scene, most old CRTs have found their ways into the garbage or into the backs of closets. For this project, it might be a good idea to pull out the old monitor or TV out and dust it off! [James] has found a way to hack the VGA input to these devices to get them to display vivid visualizations based on an audio input.

The legacy hardware-based project is called RGB.VGA.VOLT and works by taking an audio signal as an input, crossing some wires, and sending the signal through a synthesizer. The circuit then creates a high-frequency waveform that works especially well for being displayed on VGA. The video can also be channeled back through an audio waveform generator to create a unique sound to go along with the brilliant colors.

[James]’s goals with this project are to generate an aesthetic feeling with his form of art and to encourage others to build upon his work. To that end, he has released the project under an open license, and the project is thoroughly documented on his project site.

There have been plenty of hacks in the past that have implemented other protocols with VGA or implemented VGA on microcontrollers, but none that have hacked the interface entirely to create something that looks like the Star Gate sequence from 2001: A Space Odyssey. We think it’s a great piece of modern art and a novel use of VGA!

Thanks for the tip, [Kyle]!