7 ms·
DIY FPGA-based HDMI ambient lighting
- nickysielicki 11y agoI can't tell if it would be distracting or awesome.
- rando3826 11y agoAgree. Would love to hear from someone who uses this while working at their computer, and someone who uses it for viewing media on the tv.
- AceJohnny2 11y agoAwesome. It perceptually extends the image on the screen. Some companies have products based on it: https://www.google.com/search?q=philips+ambilight&tbm=isch https://www.google.com/search?q=philips+ambilight&tbm=isch http://en.wikipedia.org/wiki/Ambilight http://en.wikipedia.org/wiki/Ambilight
- white-flame 11y agoI find it strange that it's apparently desirable both to eliminate any sort of light glow/bleed on the panel itself, and manually add glow bleeding out the sides. :-P
- matmann2001 11y agoDefinitely awesome. Here's a video of mine: https://www.youtube.com/watch?v=_4KxPPr5fQc https://www.youtube.com/watch?v=_4KxPPr5fQc
- matmann2001 11y agoImpressive but overkill. I have my own ambient lighting setup. It runs on a Raspberry Pi and works like this. 1) I get the video signal from the composite output of my cable box (or any video source), which outputs HDMI and composite in parallel. If that weren't the case, I could have used an HDMI splitter and HDMI2Composite converter. I prefer the composite signal, as its not encrypted, and you don't really need to waste processing on an HD resolution signal. The "resolution" of your LEDs around your display doesn't even come close to even an SD video signal. 2) The composite cables run into a USB Video Capture card, which I picked up for pretty cheap on Amazon. The USB card is plugged into a Raspberry Pi, running Raspbian. 3) I got the driver for the video card working on Pi. Then wrote a driver for the LED strip, which communicates over SPI. 4) My main program, which is set to run on powerup, will make the video card sample the video signal as fast as it can. I do some image processing on the capture to average the pixel colors in each of several rectangular areas around the border of the image, each assigned to a corresponding LED. Then I send the SPI signal to drive the LED to that color. The sampling, image processing, and LED driving is plenty fast that the LED "frame rate" is well above perceptible limits. 5) This is all configurable with a config file that accepts parameters for LED layout, how big the area to process for each LED should be, overlapping those areas for smoother color transitions, how many frames to average the colors over (also for smoother transitions), etc. 6) The wiring is the simplest part. Power source, split off to a usb connector to power the Pi, the other line split into power and ground for the LED strip. The strip needs 2 lines for communication as part of the SPI protocol, which are just wired to appropriate GPIO pins on the Pi. Boom. Done.
- mmastrac 11y agoOverkill is the best part of personal projects. :) There's nobody saying that technical debt has to wait or that the solution in there is "good enough". It's the chance for a developer to delve deep and solve something in an interesting way, no matter how long it takes.
- dang 11y agoYou're right. And the paths that creativity follows in the unconstrained case are important. Sometimes they lead to dead ends, and sometimes to new things that never would have gotten started otherwise. I sometimes think of a distinction between the engineering way and the hacker way. Both are good, and the two are related, but they aren't the same. If HN has a purpose in the world it surely is to champion the latter, whose mottos are "gratifying curiosity" and "just because". By "the engineering way" I mean creativity operating under economic or organizational constraints that demand justification and exclude the whimsical. You end up with different projects and products that way. But I don't think matmann2001 was being critical—just eager to share the cool details of their own ambient lighting setup, which is an excellent thing to do and squarely on the hacker side of this distinction.
- mmastrac 11y agoAbsolutely agree. There's a place for both pragmatism and the artistic nature of unconstrained hacking in both the work you do for people and and side-project hacking. There's a balance that every hacker has to find. Sometimes it's good to just get something out the door, sometimes you've invented an excuse to learn technology X. :)
- matmann2001 11y agoYou captured my sentiments well. I found OP's project extremely impressive and I never meant to detract from the hard work he put into it. When I was designing my own system, doing HDMI decoding on an FPGA was an option I considered. But HDCP (a from of DRM encryption on HDMI signals) was the deal breaker. Although there has been some recent research on MITM attacks to break HDCP, it's currently beyond my budget and patience. It's much easier to sidestep HDCP altogether, which can be done with a simple AV converter.
- nsxwolf 11y agoI thought HDMI was encrypted to prevent this sort of thing? If you can do this with an FPGA what stops you from designing one that will copy a Blu ray?
- deleted 11y ago[deleted]
- white-flame 11y agoNo, HDMI offers encryption, called HDCP. Note that HDCP also existed on DVI before HDMI rolled around. The article specifically notes that he skipped HDCP support among other features.
- mikeash 11y agoAnd just to clarify, "offers encryption" means it's optional. The sender can require HDCP if it wishes, but it can also transmit plain unencrypted data. Some devices will work either way, but restrict what they do without HDCP. (For example, iTunes on a Mac won't play DRM'd videos if a non-HDCP connection is present.) Presumably whatever this guy is using for his video source doesn't require HDCP.
- fragmede 11y agoIt's just easier to rip a Bluray in software. Playing back a Bluray and ripping the video is probably going to be real time, while Bluray's will rip faster than that.
- joering2 11y agoIf it's not yet, this should be a Kickstarter project. $10 per pop and off you go to raise $1MM!
- WatchDog 11y agoIt was and it raised 500k. https://www.kickstarter.com/projects/woodenshark/lightpack-ambient-backlight-for-your-displays/description https://www.kickstarter.com/projects/woodenshark/lightpack-a...
- matmann2001 11y ago$10 for the software maybe. The cost of the parts would be much more. Strips of individually addressable LEDs are pretty expensive, even if buying in bulk.
- ChuckMcM 11y agoDamn, now I am going to own another FPGA board. That looks like a pretty fun project. Now to build the ultimate LIFE game idler :-)
- eltoozero 11y agoIt's not much less hassle to go the DIY route, I've been busy polishing off building one of these: http://www.keiang.de/Content-pid-32.html http://www.keiang.de/Content-pid-32.html PS, it's not obvious but if you email the guy he'll sell you one, also he doesn't ship to the US so don't ask me how I got mine.
- specto 11y agoHow did you get yours?
- luminositymen 11y agohave you seen this one: https://www.indiegogo.com/projects/ambivision-standalone-ambient-lighting-device/x/8427436 https://www.indiegogo.com/projects/ambivision-standalone-amb...
- slowmotiony 11y agoThis is amazing, but how would a person that doesn't want to hack around too much just buy something like this? Like a starter kit, with some device and a led strip?