# Triggering video?



## joker (Sep 25, 2007)

I was wondering if anyone is or has an idea on how to trigger video?

Lets say I want a TV to come on and then play a video to talk to guests. Maybe a home video comes on and all of sudden turns to some creepy stop motion video and the attention of the people on screen are directed directly at the audience.

Any ideas? Could a DVD player or remote be hacked like an MP3 player?


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## hedg12 (Jul 6, 2008)

Yup, you can bypass the play switch with wire leads that connect to a mat switch or a kit74 (or pretty much any other way you want to trigger it.) If you author your own DVD you could leave the menu blank, then once it's done playing the video would "rest" on the blank menu and play when it's triggered again. There might be a little delay between the time it's triggered and the start of the video, so you'd want to allow for that in your setup.

There are stand-alone solid state video players that can be triggered remotely and start to play immediately, but they're kinda pricey.


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## joker (Sep 25, 2007)

hedg12 said:


> Yup, you can bypass the play switch with wire leads that connect to a mat switch or a kit74 (or pretty much any other way you want to trigger it.) If you author your own DVD you could leave the menu blank, then once it's done playing the video would "rest" on the blank menu and play when it's triggered again. There might be a little delay between the time it's triggered and the start of the video, so you'd want to allow for that in your setup.
> 
> There are stand-alone solid state video players that can be triggered remotely and start to play immediately, but they're kinda pricey.


So you're saying you could use a PIR or mat sensor to basically take the place of the play button? I'm sure it would depend on the player, but do you have any pics or links that might assist me in this?

With a prop controller the delay time between trigger and start up wouldn't be that big of a deal as long as its consistent, otherwise any additional triggering by the prop controller might get out of sync.


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## bradbaum (Jul 26, 2008)

try this:

http://www.hometech.com/infrared/ircont.html#XA-59010

you learn the IR codes for your DVD player into it and then trigger them with a contact closure. this way you can hit play on the dvd with no modifications.


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## halloweenguy (Dec 27, 2006)

There also this solution:
http://www.nightfrights.net/controlFreak.html


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## DarkLore (Jan 25, 2009)

bradbaum said:


> try this:
> 
> http://www.hometech.com/infrared/ircont.html#XA-59010
> 
> you learn the IR codes for your DVD player into it and then trigger them with a contact closure. this way you can hit play on the dvd with no modifications.


That brings up some interesting possibilities. What about somehow triggering an IR led? That way, you wouldn't have to tear up the video player.

Or maybe sending a signal through serial or usb port to a PC to tell it when to start or stop?


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## fritz42_male (May 5, 2009)

Buy a $5 universal remote control and hack that!


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## 5artist5 (Jul 10, 2007)

You can have a microcontroller output the IR signals with an ir LED. Then you can use all sorts of triggers to make it happen and have control or pause times and what-not.


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## hedg12 (Jul 6, 2008)

fritz42_male said:


> Buy a $5 universal remote control and hack that!


That's a great idea, and definitely the cheapest way to go if you don't want to modify the dvd player.


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## hedg12 (Jul 6, 2008)

joker said:


> So you're saying you could use a PIR or mat sensor to basically take the place of the play button? I'm sure it would depend on the player, but do you have any pics or links that might assist me in this?


Sorry, I don't have any pictures but all you'd be trying to do is duplicate what the play button is doing. Most dvd players I've been into use small buttons similar to these for the front panel controls. There are usually 4 pins on each button but generally the two on the left side are common to each other, and the two on the right are common to each other. If you have access to a multimeter, you can measure the continuity between the pins and map it out pretty easily. Basically, when the button's not being pressed the pins you need won't have any connection between them, but when you press it they will. If you jumper across them the dvd player should start to play.

If you go the universal remote route, the principal's the same but the switch is different. Most remotes use a membrane type keypad. When you take the remote apart you'll see a circuit board with a bunch of little bulls eyes where the buttons are. All you need to do is find the "play" button, and use the center of the bulls eye for one lead and the outer ring for the other. If you connect the two the remote should send out the "play" command.

Clear as mud, right?


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## joker (Sep 25, 2007)

hedg12 said:


> Clear as mud, right?


Actually yeah...Thanks for the info!!


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## DarkLore (Jan 25, 2009)

Remember...universal. As in cheap a$$ remote from Walmart. So we can all do it after you figure it out. lol.


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## bradbaum (Jul 26, 2008)

I forgot that the PICAXE controller chips can send IR,

Keep in mind IR signals for consumer electronics are modulated at either 38Khz or 40Khz.

So you will need a square wave oscillator, that the output of the PICAXE will then ride on before it hits the IR LED.

I think it may be easier to hack the remote.


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## Scottzilla (Jun 13, 2007)

Another zero-delay and possibly free method (depending on what you have at your house already) would be to put the video on a laptop. Load it up in Winamp or something, set it to full-screen mode, then connect the video out to your TV. Hack an old keyboard so that whenever your sensor is tripped it presses the 'x' key on the laptop. Your video will start instantly.

keyboard hack how-to:
http://www.automat3d.com/electronics/keyboard-hack/


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## fritz42_male (May 5, 2009)

bradbaum said:


> I forgot that the PICAXE controller chips can send IR,
> 
> Keep in mind IR signals for consumer electronics are modulated at either 38Khz or 40Khz.
> 
> ...


Picaxes can send IR but AFAIK only Sony codes. If the DVD is a Sony, this would be an easy solution. 
If the DVD isn't a Sony, you could always wire a picaxe to the play button on a universal remote control.

Anyone want my $10 prop controller howto?

I'm using code provided by hpropman on one of these as a random head movement for a Grip Reaper prop.


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