Adaptive ambient light for movies

posted Jul 10th 2006 1:00am by Eliot Phillips
filed under: Uncategorized

[RafkeP] from Divxstation has created this clever hack to clone the Philips Electronics Ambilight technology used in their flat-panels. Ambilight is an RGB backlight that changes color based on the on-screen image. It’s supposed to make the viewing experience more comfortable. The MoMoLight uses a directshow filter to calculate the average color on the top, left and right border of the screen. It sends this information to a microcontroller that does PWM control of three separate banks of red, green and blue cold-cathodes. LEDs could be used instead. Monitoring the top, left and right would be called Ambilight 3 according to Philips’s naming scheme, which doesn’t actually exist yet.

[thanks mathias vdb]

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Comments [24]

Reader Comments

cool, definately like the idea of saving hundreds of dollars, though, the bigger screen would be nice

Posted at 2:10 pm on Jul 10th, 2006 by antiwhack

antiwhack:

That’s fine… so you have a generic big flatpanel tv, and a laptop displaying the same image… the laptop does the calculations, and drives rgb lights that are on the back of your TV. Boom, ambient light for your TV.

Posted at 2:17 pm on Jul 10th, 2006 by ner

Wish you could use it for games, that would be badass

Posted at 2:40 pm on Jul 10th, 2006 by aaron

Awesome hack. I think I would use an LED array instead of CCFLs. The author commented that he didn’t know if the flicker was because of using the ccfls. I’m thinking it is, as that type of lighting is very similar as far as voltage behavior to florescent lighting. I know there special dimming florescent fixtures, but I have never seen a dimmable ccfl.

Posted at 2:43 pm on Jul 10th, 2006 by pretorious

Very nicely done. Aaron and Antiwhack might be on to something, too. If you’ve got a video capture card, you could have a laptop driving the banks of CC lights. You’d be able to use it for video games, too.

Posted at 2:51 pm on Jul 10th, 2006 by Jo

#2. yeah, i see how it works, but i’d still like to own a flatscreen, i don’t own a laptop, so i’d probably end up mounting a tv as my second monitor if i wanted anything bigger than my current monitor. It’d be cool to be able to do this straight through s-video, so i wouldn’t have to clone the screen over. maybe an s-video – vga cable?

Posted at 2:53 pm on Jul 10th, 2006 by antiwhack

It would be cool to light the hole of your movie room using ambilight. Would it be possible to have a program that you could preset timings for the colour? so you could make your room look like its a sunny day when your looking at green fields. If you could do that then you could also have it set the room tempature by linking it to your air con and heater.

Posted at 3:12 pm on Jul 10th, 2006 by Spud

Pretty sweet hack. I would probably do it with LED clusters as well… but still a great concept.

I wonder if it would be possible to simplify the interface any further though. Say pulses off of a parallel port?

Alternatively, it would be even more useful if it could do this straight from a component video signal… I wonder how hard that would be to rig up? Could you just use an ADC on each color line to measure intensity? Or am I totally misunderstanding the way that component video works?

Of course even if that did work it wouldn’t produce the kinds of two-channel effects that this system creates which would make it less cool.

Posted at 3:16 pm on Jul 10th, 2006 by bp

I think a few people have hit it right on the head. Use a dedicated machine to take a split line from the composite video into its input to constantly have the overlay open and always have your tv doing what a phillip’s tv would. Perfect.

Posted at 3:29 pm on Jul 10th, 2006 by snorkle256

I thought at first that would be annoying but from the video it looks pretty cool too bad i couldnt have that on my normal tv :(

Posted at 4:00 pm on Jul 10th, 2006 by Tom Parker

This is awesome, I thought of this a while ago but never did anything.

Posted at 4:43 pm on Jul 10th, 2006 by mastershake916

This is cool but would be so much better for dell xps users if they can get it to use the RGB led’s already built in to the putar. hmmmmm

Posted at 4:51 pm on Jul 10th, 2006 by alex

I still have 6 RGB LED bars in my room that I need to make a PCB for. I was looking for such directshow filter before but found none. Thanks.

Posted at 6:42 pm on Jul 10th, 2006 by rafael vuijk

How about 5-wire rope light?
http://actionlighting.com/item-detail.asp?ID=680&MainCategory=Rope%20Light&Sub=5%20Wire%20Rope
It works with 120 volts, so I guess you could somehow wire the hot of the electrical line so the pc board is like a switch

Posted at 6:51 pm on Jul 10th, 2006 by greg

hackaday down for maintenance last night?

Posted at 4:39 pm on Jul 11th, 2006 by antiwhack

high fives all round for leds, am i right?

Posted at 4:44 pm on Jul 11th, 2006 by jim

well here we go againe more light projects so sad there must be more to life come on u lardey arss yankees get ur fingers out give me some good projects

Posted at 6:04 pm on Jul 11th, 2006 by steve

This is what hackaday is all about. This is one of the sweetest ideas I’ve ever seen.

I could be wrong, but it seems like CCFLs have a more ambient cast to them and they avoid any break or areas where the led light doesnt overlap.
Also i think a translucent piece on the viewer’s side that would let it light up the front and still cast a light on the wall would help alot in the daytime

Posted at 6:59 pm on Jul 11th, 2006 by velocityphilosophy

Spud’s gave me an interesting idea.. having ambient light in your house set up to be tempreture sensitive.. so if you turned on the AC the light in the room would take a bluish tinge and if your were to say light the fireplace the room would take on an orange glow

but i’m sure this has been done

Posted at 10:26 pm on Jul 11th, 2006 by g0d

I’ve been looking all over the net for a project like that, i just wish it could be hooked straight to a video source…. Is anybody out there with some knowledge capable to modify it to accept a raw video input??? It would LOOK beautifu behind my living room 37 inches plasma…. ;) anybody???

Posted at 1:40 am on Jul 12th, 2006 by Dre

Could you use this on a DIY DVR for you flatscreen?

Posted at 1:53 am on Jul 12th, 2006 by Jacob

19> YES! if you are running windows and your DVR program supports his filter.

Posted at 7:24 am on Jul 12th, 2006 by rmiller021

Here’s an idea: VLC can take a stream direct from a capture source, apply DirectShow filters to it and spit it back out again… could be useful.

Posted at 7:50 am on Jul 15th, 2006 by ex-parrot

Also was looking to build this, but then found some interesting on google.

A Dutch company is selling this sort of product for quite some time now. Their products claims to work with all games and applications.

They also seem to have some nifty new adons that even look more cool. The site mentions artficial scene recognition that “reads” fire heat and smoke, which than can be send as effect to your own hardware..
i.e. heaters and smoke machines!

real interesting..
They even seem to offer a free SDK, will download and take a peek ;)

Posted at 8:25 am on Aug 31st, 2007 by pennywise