Video distribution amplifiers are used to amplify a video signal and split it into multiple outputs so multiple displays can be driven. They are also used to correct the gain of an incoming video signal. [Andrew] was having trouble with the video signal from an interferometer, and found the issue was caused by a low output gain. His solution was to build his own video distribution amplifier.
The THS7374 appeared to be the perfect chip for this application. It’s a four channel video amplifier IC, and only requires a few passive components to run. The only problem was the package: a 14 pin TSSOP with 0.65 mm pitch. Not fun to solder by hand, especially if you don’t have a PCB.
[Andrew]’s solution was to build his own breakout out of copper-clad board. He worked under a microscope and cut out a pattern for the part, then soldered 30 AWG wire to the pins to make connections. After cleaning off any copper that could cause a short, the board was working, and the video waveform looked great on an oscilloscope.
After testing, even more gain was needed. [Andrew] ended up cascading two of the amplifiers. This method of prototyping doesn’t look easy, but could be worth it when you need a single board.
This television is perfect except for its low resolution and the fact that it can’t be seen by the naked eye. [Chris Shen’s] art installation, Infra, uses 625 television remotes as pixels for a TV screen. There’s a little bit of insight to be gained from the details which [Chris] shared with EMSL.
The remote controls were all throw-aways. Even if there are problems with the buttons, battery connectors, or cases, chances are the IR led in each was still functional. So [Chris] patched into them using about 500 meters of speaker wire.
Why 625 pixel? Because that’s how many LEDs the Peggy board can handle. We’ve seen this open source LED board driving video in other projects. Here it’s been connected to each remote using Molex connectors. Each of the headers has the same pitch as a through-hole 5mm LED. The entire board was filled with them, and a mating crimp connector terminates the end of the wire coming out of each remote. This makes setup quite easy as the remotes don’t have to be installed in any particular order as long as the physical location matches Peggy’s grid.
You can get a glimpse of the piece playing video in the clip after the break.
Continue reading “Infra is a television made of Infrared pixels”
We’re starting a few new things at hackaday. As always, our goal is to share awesome hacks from as diverse a crowd as possible. We’ve played with video a bit before, but now we’re really going to start having some fun with it.
Our first exploration into this area was the hacked portal gun. People enjoyed looking at it, and those seeking more in depth technical knowledge came to the site to get it. Instead of focusing the video on the technology or the build itself, we used it as an interesting way to get the attention of people with relevant interests. This video proved to us that our idea was solid.
We have now stepped up our production in terms of quality and quantity. We will be releasing videos that may be humorous, like a fake commercial or skit, or may be serious in the style of a documentary. They will all have some kind of hack at their core and that hack will be broken down in an article here.
I would also like to extend the opportunity for you to help. There are two ways you can do so:
- Sign up for our email list(it is in the right column). I’ll be sharing behind the scenes info and previews about upcoming video projects and asking for ideas on how to improve them. The list will be very informal, and only deal with behind the scenes kind of stuff it will not be a mailing of the daily posts.
- Submit a project or idea that you think would make a cool video. You can email that directly to caleb@. Of course, we would prefer projects that haven’t been released yet, but that isn’t necessary. We’re looking for things that are visually stunning, or could possibly have highly cinematic potential. Not necessarily the most technically difficult thing.
We hope to start releasing videos next week, so keep your eyes peeled. We filmed all week, and my cheeks hurt from laughing so much.
Here’s two photographic takes on the same subject, each with a different depth of focus. [Chaos Collective] came up with a way to make interactive still images that allow a user to adjust the depth of focus by clicking on different objects in the image.
This was inspired by the Lytro camera which uses an array of lenses to take multiple pictures at once. Each of those images has a slightly different depth of focus. The technique used here doesn’t require that you buy one of those $400+ cameras. But it’s not a cheap hack unless you already own a camera that can shoot video and has manual focus.
The technique used by the [Chaos Collective] is to move the camera’s manual focus setting from the nearest to the furthest target while capturing a video. That file can then be processed using their browser-based tool which turns it into an embedded HTML5 image.
Air travellers take note, [Asthmaticatom] figured out how to comfortably watch your own videos on the plane. We know you always have your phone with you, now you just need to find a barf bag. A little bit of papercraft turns the waste disposal device into a neat little hanging dock.
The bag in the image above is actually upside down. A rectangle the same size as your phone’s screen is ripped out of the top. The metal clasp used to seal the top of the bag is rolled up to hold the phone securely in place. The bottom of the sack has a flap which acts as a one-way catch. When it is shoved into the crevice on top of the monitor it holds the whole thing in place.
Of course we don’t remember ever having been on a plane where there was a monitor in the seat in front of us, but perhaps we’re just buying tickets on the wrong airlines.
[Berto] wrote in to tell us about the visual effects synthesizer he built. It works as a pass-through for a video signal, rendering crisp clean images into a more psychedelic flavor like the one seen above. On the one hand this does a dishonor to the high-quality video devices we carry around in our pockets these days. On the other hand it will make some really interesting background video at a party or at your local dance club.
This is not a filter for a PC, or an FPGA-based processing system. A set of analog parts alter the incoming composite video (NTSC or PAL formats) and pipes the result to a television or projector. [Berto] included controls to alter the effects. They’re mounted on a panel and everything is given a home inside of a handy carrying case. Check out the video clip after the break to get a better idea of the video manipulations this things can pull off.
Continue reading “VISUALIST – a hardware visual effects synthesizer”
Watching Big Buck Bunny on a spinning POV display is pretty impressive. Sure, the circular display area cuts off some of the picture, but otherwise it looks fantastic. This POV display is based on a Gumstix board. It runs embedded Linux which makes video playback rather easy. But translating each frame to the round display is another story.
The device is the result of a course project at Telecom ParisTech. [Félix], [Sylvain], and [Jérémy] used an FPGA to do the pixel mapping. This uses an encoder wheel (rather than a traditional hall effect sensor) to ascertain the blade’s position. The sensor that monitors the disc sends quadrature encoded pulses which result in 10-bit position data. The FPGA uses that data to calculate where each LED falls in its arc, then looks up the pixel color for that position. It’s not the largest POV display we’ve seen, but it certainly has the very best RGB resolution by far.
Continue reading “Full-color video on a spinning POV display”