project concept, dont know where to start

Hi fellow arduino enthusiasts, I am struggling to complete a concept and need help with one aspect of it.

I know what I want to do, but dont know what to do.. i am sure arduino have some special boards to do it, just now sure myself.

My Goal is to have a project where the arduino listens to a video being played at XX intervals, then turn on a light.. using possibly an audio track in the video to create a timing base.

I will design a special audio plug where the device being used to play the video, I will allow a stereo channel to have the left channel going to both speakers and the right channel can be used for the project.

here are the 2 ideas which need to be combined.

firstly, completed already..
I will make arduino control a mosfet which activates a my device on a high/low pin output..
the output will actually be light.

secondly,
the arduino needs to know when to turn the light on and off from my video playing..

thanks guys.. :slight_smile:

You need some signal from your video player, that tells the Arduino when a video is played. Consult the documentation of your player, what signals are available.

Do you have control of the video content or, is it to be prerecorded?

hi,

i will make a video, I have total understanding of using things like blender, photoshop, vegas, premiere, photo, video and audio tools, so I can simply modify video to embed a tone at x points.

so i need to know how to make arduino pickup this noise

if possible here is where it gets hard...
i would like to possibly add different types of tones.. for different detection...
would this be hard to do?

thx

toxsickcity:
if possible here is where it gets hard...
i would like to possibly add different types of tones.. for different detection...
would this be hard to do?

thx

I haven't the faintest idea of the difficulty. I can think of two possible methods.

Tones: if you can lay down modulation of some sort by some means then yes, hardware can be built to decode/detect whatever frequency you want. I think you'd need a circuit for each frequency of interest. OR, a lot of the IR remote projects use the Arduino itself as a frequency detector for decoding various manufacturer's transmit protocols (in the 38KHz range). I suspect though, that an Arduino watching for tones to decode wouldn't also be able to run whatever else you've got going on. I could be wrong.

I don't know the details of its operation but, if you can embed closed captioning perhaps you could extract useful information by that route.

For pre-recorded video I'd suggest a pre-programmed Arduino response.That'd be much easier to implement than trying to have it listen to specific frequencies.

Basically a list of times and responses, then all that's left is making sure they're started at the same time. You could do that by IR remote: have the command that starts the video, also start the Arduino.

For detecting frequencies indeed I guess you'd need a circuit for each of them (LC based filter with amplifier or so). Not sure if the Arduino itself has the power to do real-time frequency analyses of sounds, and handle all your other actions in time. Also of course this way the action is after the sound is detected, so not the moment the specific sound starts. The delay will be short, so may not be an issue for your application.

wvmarle:
For pre-recorded video I'd suggest a pre-programmed Arduino response.That'd be much easier to implement than trying to have it listen to specific frequencies.

I think the OP wants to be able to "program" the lights by just fiddling with the video and not touching the Arduino program.

I'd use DTMF signals. Look into that. I bet there are some decoder libraries for Arduino. The encoding could be done in Audacity, since you anyway need something for editing the video soundtrack. You should mix left and right channel into one mono channel. Then create another channel with the DTMF signals. Then create one stereo channel from these two channels.

found on ebay a little circuit which gives me 5 pinout for audio/voice detection.

i believe this will take my input audio, detect it over the audio band usually 20hz-22khz and splits into
0-5kh
6-10kh
11-15kh
16-20kh
20-25kh or such

it didnt say it but saw another citcuit much more expensivie looking similar...

https://www.ebay.com.au/itm/DTMF-MT8870-Audio-Decoder-Modules-Smart-Home-Controller-Voice-Phone-Control-New/191982509346?hash=item2cb30c9d22:m:mxY_8rPuAtX21MSGSuiLVhw

what do you think?

having 6 channels would be great... (6 sound tones) exactly what i wanted..

How do you like to edit the audio track? Do you want to be able to trigger all 6 pins simultaneously with one mixed sound, or is it enough to trigger them one by one with say 5 ms intervals?

Make sure whatever digital format you use for your audio it can actually reproduce ultrasonic signals. 22 kHz is the technical limit for a standard 44 kHz sampling rate as used in uncompressed CD audio. Compressed audio may discard those signals as they're inaudible anyway.
The lower ranges should pose no issues.

Could you use something like the VideoExperimenter, and put a signal in blanking, like a line (or half a line) that's either black or white?
Or does it have to be an audio tone?

everytime I read 44hkz.. i never think about that.. did you mean 44 is actually 22kh x 2 channel?
thats something i workwith almost everyday and never thought about that

i hope thats what you meant.

with respects to having multiple at the same time.. possibly/ possibly not.. will know more once the kit arrives..
same goes for delays.. I dont know the kits sensitivity either.. or delays!!!
It might be really highly responsive and give me real time working. I assume running a tone at the same time that has bass and treble at the same time (ie music) i assume running multiple channels at the same time might be possible...
the only thing I dont know if how the little circuits response time will be.. like maybe without error can only read once every second haha I dont really know..

on the last message something i am pretty interested in is embedding and hiding codes into video, but for this project.... maybe NOT hehehe
id really love to play with some kind of video experienter adding half lines etc to video would be really cool idea..
but i imagine that i would be requiring extra special equipment for the arduino to read it,
i simply want to use the arduino project and plug it into a TV or Laptop, computer, cd player and make it work..

so I assume audio track should work fine!!!

thanks for the messages..

P.S. I have posted here a few times about my wall computer project and my very troublesome code..

I remember one user said just keep looking and learning and eventually instead of rebuilding my code to work from onewire sensors to ntc, i just made a brand new code and now it's so streamlined.. I no longer have stupid issues I did before.. so

same goes.. thanks for support here...

shaun

toxsickcity:
everytime I read 44hkz.. i never think about that.. did you mean 44 is actually 22kh x 2 channel?
thats something i workwith almost everyday and never thought about that

No, 44 kHz sampling rate per channel.

That means the highest frequency you can possibly encode is 22 kHz - this as you need at least two samples per period to form a waveform (in that case, a block wave is the only possible: on sample high, second low, third high, fourth low - that'd be two periods in four samples).

Video/DVD generally uses a 48KHz sampling rate giving you a theoretical sampled frequency limit of 24KHz.

But I'm with Johan_Ha, DTMF looks like a good way to go. That gives you 16 possible "channels" and it's easy enough to get an encoder to record the signal using Audacity or something similar. You could do the decoding in the Arduino itself but it would probably be easier using something like Arduino DTMF Shield - DFRobot or you could make your own equivalent using an MT8870 IC.

There are all sorts of possibilities.

Steve