Forums > Jitter

Newbie: Jitter video random and webcam

Oct 04 2011 | 4:46 pm

Hi guys!

This is my first post here and my first contact with MAX 5 started yesterday! So, my problems so far are vast…

The project that I intend to do is a box (real live box lol), that only has a button, a motion sensor (webcam) and a monitor. The purpose of that is for when someone passes in front of the box the sensor captures it and a 10 second movie is displayed on the monitor.

By now, I’ve gather some really useful information. For example use a webcam as a motion detector. Using Vizzies, moviefldr to have there all my videos and the vizzie player to have them displayed. But now, the problems begin.

1st: I don’t know what patchers to use to connect the webcam to max and furthermore to have the webcam not transmitting images to MAX but just picking up the movement and work as a Bang so that in the moviefldr triggers the video. Other problem is how do I set up the random movie. I’ve put 2 videos in a folder, got a button on top, connected to an object "Random" and then connected to the moviefldr and then connected to a plyr. But when I hit the button it only starts one of the movies and never the other… if it is random it show randomly at least once start the second film.

Other problem that I have is, should I use jitter? I’ve done the begginers tutorials on and jt.window but I haven’t been able to associate a specific movie file to… how do I load a video to it?

Now, for the button, the actual button, I would like for someone to press it and a photo to appear also for 10 seconds! Do I have to rig some kind of game-pad console to get that?

For the movies also, I want to have them displayed for ten seconds at a time when the webcam picks up movement, but I want the monitor to go black again. Imagine a black screen, you trigger the webcam, a 10 sec. movie appears and then the screen goes black again until you activate the webcam again with movement. (the monitor part I think I have it solved, I connect a second monitor to my laptop having it in full screen and MAX running on my native’s laptop monitor so I thing that is shouldn’t be a problem, I just don’t want for the last frame of the last movie displayed to be frozen on the monitor until someone else triggers the webcam.)

Sorry for all the questions and problems… But if you could help me it would be amazing.

Thank you very much


Oct 05 2011 | 11:59 am

Well there are a lot of questions there, but basically for the motion sensor, a web cam can only capture images based on a frame rate, there is no way of picking motion out of them, unless, you have two feeds (created in Max/MSP using Jitter) then some method of comparing the raw data generated by each.

Firstly, to get a web cam to display as a device there’s a complicated sequence of objects, which you will be able to find on google or in the Jitter help files, then you have to reconfigure the patch to get it to work for you.

Set up two video feeds, extract raw data from each then have some case scenarios which compare the data, so that when the still image changes (someone walks in front) it activates the video feeds.

We did have an example of exactly what you are trying to do, but can’t find it unfortunately, otherwise we would send it to you.

Drop us an email and if we discover it we will let you know.


1st Creative Labs Support Team

Oct 05 2011 | 5:16 pm

Hi guys!

First of all thank you for your help.

Now, down to business. I've already was able to have a feed from a webcam to get to MAX. Yeahhh! (sorry for the enthusiasm lol)

Now, for the video feeds that you talked about… I really didn't get it! I got some patches, examples, but what they do is applying effects to feeds from the webcam… I can't understand how I can connect the feed from the webcam to activate as a motion sensor. What I thought, and it might be easier is getting some patch for getting robbers, like a security cam feature in MAX but instead of activating an alarm, it activates the videos I what to display. Do you think it, is a valid way to solve my problem?

Regarding the example you fellas talked about, I found one. It's pretty close to what I want to achieve: the only problem is that this guys are on a level that I can't achieve in a million years lol sensors, make controller…

I wanted to post here my patch but I don't know why so I posted a .png image file saved from MAX 5.

Thanks for your help

Nock :)


  1. 1stpatch.png


Oct 05 2011 | 5:53 pm

So I found this here:

the number 32 seems to be what I need… I’m going to give it a try!

Oct 09 2011 | 10:20 pm

Hey guys! I’m having a lot of trouble with the link I’ve found… I can’t figure out what this means:

"To get the difference between consecutive frames, we use jit.op @op absdiff. This will show us the amount of movement between frames. We then use a jit.op to do apply a threshold. This will give us a binary image.

This image is then fed through jit.slide to remove flickering and smooth out the data flow."

I can’t add this objects to my patch…

Can somebody help me?

Thanks a lot :)


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