Forums > MaxMSP

Capturing webcam images and audio

August 26, 2010 | 8:43 am

Hi all,

i came to the cycling 74 forum cause i have a problem i think i can solve with some of their products but am not experienced in using any of them. Can you let me know if this idea is possible…

I’ve been using a webcam recently to capture images every 15 seconds and then put them together into time lapse videos. What id’ like to do is to also capture a snippet of audio with each of the images, either using the webcam’s mic or another one plugged into my laptop/pc. I want the viewers to get an audio snapshot that matches the visual snapshot. Whether it sounds good in the final edit will be debatable but i’d like to try it anyway.

If i know that the frmerate of the final movie is going to be 15 frames per second then i would want to capture 66.67 milliseconds of audio (1,000 milliseconds divided by 15 frames per second) and save it in it’s own audio file or keep adding it to an existing audio file. This means that when the video is finally combined together i can add the audio on top of it and it should match perfectly. (Of course, being a sound engineer, i know it would be more complicated than that. I would want to be working with samples based on the audio sample rate, not just milliseconds, but you get the idea i hope. e.g. 44,100 audio samples per second divided by 15 frames per second in the final video’s edit comes to exactly 2,940 audio samples for each audio snapshot.)

Can anyone tell me if there is an existing max/msp, jitter or other project, which captures images from a webcam and it would be possible for me to modify (hopefully with some help from someone) to also capture the audio and store it at the same time.

Cheers

NM


August 26, 2010 | 9:38 am

I don’t know if there is an existing project, but… The jitter object, jit.vcr captures video with audio, you could feed it from jit.qt.grab for the webcam feed and give it the audio in at the same time, then you would just need to set up a trigger to take your snap shots.It wouldn’t be too involved, but if you don’t know Max or something similar then its a bit of a learning curve. Also, jit.vcr is quick time based so you want to be on a mac or using appropriate Windows VDIG (can point you in right direction). If you haven’t already downloaded the demo then maybe give it a go.


August 27, 2010 | 10:24 am

Hi,

i’ve installed the demo and been mucking about with some tutorials. The problem is that i think the demo version is limited to the components you can use. there are only 3 available in the Jitter category. Is that the case with the demo version? would i need to get the full version to access all of the components and modules?

Cheers


August 27, 2010 | 10:34 am

Ah, lol, just figured it out i think. i should have started with the very first tutorial before going deeper into the program. My bad. I’ve used similar programs for making vst effects and synths before and assumed this would work the same way. You know what they say about assumptions eh?

Cheers

NM


August 28, 2010 | 12:18 pm

Cool, have fun with your 30 days!

Just thinking, sticking your movies together afterwards might be a pain, not sure if you can open an image sequence of mov’s like you can with stills. There may be a way to append mov/audio to an existing file, but I can’t think of it offhand. The jit.qt.movie object has a lot of editing parameters, maybe you can set up an auto cut and paste or something.


Viewing 5 posts - 1 through 5 (of 5 total)