Change the TV channel over IP


[Mustafa Dur] wrote in to tell us about his hack to control the television with a smartphone. Now the one-IR-remote-to-rule-them hacks have been gaining popularity lately so we assumed that’s how he was doing it. We were wrong. He’s using his satellite receiver to provide the Internet connection. It pushes commands to his LG 47LH50 TV which has an RS-232 port.

The image above is the back of another LG television (it came from a forum post about controlling the TV with a PC). [Mustafa] is using a Dreambox DM800 satellite receiver which also has a serial port an he can telnet into it. He searched around the Internet and discovered that it should be possible to connect the two using a null modem cable. His initial tests resulted in no response, but a tweak to the com port settings of the box got his first command to shut off the television. After a bit of tweaking he was able to lock in reliable communications which he made persistent by writing his own startup script. From there he got to work on a Python script which works as the backend for a web-based control interface.

If you want to find out what else you can do with this type of serial connection read about this hack which used a script to try every possible command combination.

No computer Ambilight clone uses a computer


It may seem confusing that you’re looking at a Raspberry Pi when this hack is about an Ambilight clone system that doesn’t need a computer. The point here is that this system works no matter what your video source is, where many projects in the past have required the video to be playing from a computer.

This hack follows in the same path of the ARM based custom job we was almost a month ago. Just like that project you use an HDMI splitter to gain access to the feed going to your television. The split signal is fed into an HDMI to composite video adapter. The composite signal is captured by a USB video encoder. The GPIO header drives a strip of addressable RGB LEDs. The whole thing is powered as one using a bit of cable hacking.

It’s slightly convoluted. But all of the components are easy to source and relatively cheap. The one caveat is that it works best if you are already using a hardware HDMI source selector instead of the one build into your TV. That way there is just one HDMI cable going to the television, and this can siphon off of that feed.

[Read more...]

Android hack adds missing Chromecast button to Netflix app


We finally got our hands on a Chromecast over the weekend and we love it! But it wasn’t without a bit of a speed bump. Including a quick initial setup, we had a YouTube video playing in our living room about three minutes after the package hit our mailbox. But we spent the next twenty minutes feeling like a moron because we couldn’t get the Netflix app on an Android phone to cast the video. Turns out there is a bug in the Netflix app that doesn’t add the Chromecast icon for all devices.

The issue is that the newest version of the Netflix app isn’t pushed to all devices. A fix is on the way, but we’re not good at waiting. We used this technique to trick Netflix into thinking we have different hardware. Notice from the screenshots above that one lists our device as an LG-P769 manufactured by LGE. That’s how our /system/build.prop file originally looked. By using the BuildProp Editor app we changed those settings to Nexus S by samsung. After rebooting several of our apps were missing from the app drawer, including Netflix. But they all still worked hitting the Play Store for reinstallation and we now have no problem casting Netflix.

Leapcast emulates Chromecast in your Chrome browser


Our Chrome browser thinks it’s a Chromecast dongle. Here’s a screenshot of it playing a YouTube video. Note the tile banner and onscreen controls which are just like the ones you’d see on the actual hardware. Give it a try yourself by downloading the Leapcast Python package which [dz0ny] programmed.

After cloning the GitHub repo we had a few problems compiling the package. Turns out we needed to install python-dev and that took care of it. Starting the daemon is a simple command, we specified our Chrome binary path as well as added a few flags

leapcast --name HAD --chrome /usr/bin/google-chrome --fullscreen

Once that was running the Android YouTube app automatically detected Leapcast as a Chromecast device. It gave us a tutorial overlay mentioning the new share icon on the interface. Pressing that icon during playback launched an Incognito window which played the video. [dz0ny] links to a device config JSON file in the README. If you check it out you’ll notice that Netflix is listed as “external” while the others are not. This is because the Chromecast protocol uses a binary for Netflix. The others do it with local websockets or a cloud proxy so they work just fine with this setup.

How to play a Game Boy emulator on Chromecast


It’s small, it’s blurry, but it’s working. Here’s a proof of concept for playing emulators on a Chromecast which uses the original Game Boy as an example.

Notice that there are two screens shown in the demo. Out of focus in the background is the television with the Chromecast displaying the game play. In the foreground is a computer with a browser open which lists off the control setup. These are the button mappings for an Xbox 360 controller. The emulator is a JavaScript Game Boy emulator. This is loaded on the Chromecast through a simple html file (called the receiver in the repo). The sender — also a simple html file — loads another JavaScript package on the computer which translates the controller’s button presses to keyboard inputs and sends them out to the receiver.

This puts stars in our eyes about emulator hacks. We’d love to see this boiled down to smartphone and Chromecast as the two pieces of hardware, with the touchscreen as the gaming input.

[Read more...]

HDTV antenna of a different color


We’ve seen our share of commercially available HDTV antennas that work really poorly. For at least four years now we’ve gone without cable television, using a coat hanger antenna we made ourselves to record over-the-air broadcasts. But it’s a pretty ugly beast — we’re lucky enough to have an attic in which it can be hidden. If you’re in need of free television and don’t want an eyesore of a an antenna try building this foil and cardboard version. Even it if doesn’t work at all you’re only out about ten bucks.

The expensive part is the matching transformer which converts screw terminals to a coaxial cable connection so that it may be connected to your HDTV. You’ll need a few nuts and bolts, but we assume you can beg, borrow, or steal the tin foil, cardboard, and glue that round out the parts list. Glue, measure, cut, fold, fasten, finished! You’ll be watching horrible summer TV in no time!

If it doesn’t perform as expected just reuse that connector and try your luck with a fractal antenna.

Ambilight clone uses video pass-through; needs no computer


To the best of our knowledge all of the Ambilight clones we’ve covered over the years have one thing in common. They need a computer to do the image processing. This one is different. The PCB seen on the left right is all you need for the video processing. The project is called SCIMO and is the handiwork of a hacker named [Keiang].

There are only few times that the DRM built into the HDMI standard has pissed us off. This is one of them. Because of HDCP and licensing issued revolving around HDMI [Keiang] didn’t use HDMI pass through. Instead he uses an HDMI to S-Video converter. This board acts as an S-Video pass through, analyzing the signal using an STM32 ARM chip before the video signal continues on to the television. It still produces a respectable picture, but wouldn’t it have been cleaner if he could have gone with the HDMI standard?

UPDATE: Thanks for the comments on this. It looks like the TV is getting an HDMI signal. The board is fed by the HDMI to S-Video converter which itself is getting HDMI in parallel with the television thanks to a splitter.

Where other examples use Boblight on a PC for processing this manages to do so as a standalone embedded system. It also offers quite a bit of flexibility when it comes to choosing the LEDs, supporting pixels that use DMX512, WS28xx, or TM18xx protocols.

[Read more...]


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