Hi,
Have tried searching this one, but no results - maybe I'm looking for the wrong things!
I'm looking for some pointers on motion tracking preferably in PD, but maybe in another app if it's more suited. Please forgive these broad queries about dev techniques...I'm still new to this game, and although now somewhat capable at picking apart other people's examples and learning that way, I'm not great yet at figuring out ways to start things from scratch!
Basically, I'm looking to use a webcam (i-sight f.wire) to capture the actions of people in front of a projector screen, basically simulating shadows/representations. I want these 'shadows' to remain on the screen for longer depending on how long they stand there. Also, when they move, I want a shadow to follow them on the screen like a trail. I.e. A fainter shadow for passing motion that will disappear quickly, but a more intense shadow that stays for longer if the person stands still.
I thought a way I could do this would be to constantly capture images of people, say every 5 secs, and overlay these images onto the screen for a set amount of time. Therefore, if a person stood still for longer then more layers of these images would build up, therefore taking longer to disappear. But I would need some kind of tracking system to only image the movement, otherwise I would be constantly photographing the background and/or the empty room!
What things/considerations should I be at looking at to achieve something like this if it is possible? Can PD or GEM etc grab stills from a webcam?
Apologies for long mail, hope all is understood!
Cheers Jonathan
P.S. I've been looking at alternative systems using the new Flash 8 and Processing. But I'd prefer a PD based solution if poss, as I'm (currently!) no programmer!
pix_video pix_movement pix_blob pix_background etc..
On 4/15/06, Jonathan Goodwin jonathan@jgoodwin.co.uk wrote: ...some words...
Thanks...I¹m on the case!
P.S It made me laugh how you abbreviated my epic email to ³...some words!...²
Jonathan
On 16/4/06 00:02, "chris clepper" cgc@humboldtblvd.com wrote:
pix_video pix_movement pix_blob pix_background etc..
On 4/15/06, Jonathan Goodwin <jonathan@jgoodwin.co.uk mailto:jonathan@jgoodwin.co.uk > wrote: ...some words...
pix_snap2tex
Jonathan Goodwin a écrit :
Thanks...I¹m on the case!
P.S It made me laugh how you abbreviated my epic email to ³...some words!...²
Jonathan
On 16/4/06 00:02, "chris clepper" cgc@humboldtblvd.com wrote:
pix_video pix_movement pix_blob pix_background etc..
On 4/15/06, Jonathan Goodwin <jonathan@jgoodwin.co.uk mailto:jonathan@jgoodwin.co.uk > wrote: ...some words...
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Alexandre, this looks like it will be really useful, but I can't get it to work.
It works in the example patch, and if I run my patch and the example patch at the same time then it works. But if I copy the main [pix_sanp2tex] mechanisms to my patch it doesn't work. The only difference is I'm not trying to draw any geos like spheres like in the example.
I'm trying to grab images from my webcam. I'm guessing I may need to implement some kind of buffer setup, but I'm struggling to understand how that works. What does the help file mean when it speaks of the 'index of the frame in the buffer'?
On 16/4/06 03:22, "Alexandre Quessy" listes@sourcelibre.com wrote:
pix_snap2tex
Jonathan Goodwin a écrit :
Thanks...I¹m on the case!
P.S It made me laugh how you abbreviated my epic email to ³...some words!...²
Jonathan
On 16/4/06 00:02, "chris clepper" cgc@humboldtblvd.com wrote:
pix_video pix_movement pix_blob pix_background etc..
On 4/15/06, Jonathan Goodwin <jonathan@jgoodwin.co.uk mailto:jonathan@jgoodwin.co.uk > wrote: ...some words...
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Try pix_buffer to hold one or more frames in memory.
On 4/16/06, Jonathan Goodwin jonathan@jgoodwin.co.uk wrote:
Alexandre, this looks like it will be really useful, but I can't get it to work.
It works in the example patch, and if I run my patch and the example patch at the same time then it works. But if I copy the main [pix_sanp2tex] mechanisms to my patch it doesn't work. The only difference is I'm not trying to draw any geos like spheres like in the example.
I'm trying to grab images from my webcam. I'm guessing I may need to implement some kind of buffer setup, but I'm struggling to understand how that works. What does the help file mean when it speaks of the 'index of the frame in the buffer'?
On 16/4/06 03:22, "Alexandre Quessy" listes@sourcelibre.com wrote:
pix_snap2tex
Jonathan Goodwin a écrit :
Thanks...I¹m on the case!
P.S It made me laugh how you abbreviated my epic email to ³...some words!...²
Jonathan
On 16/4/06 00:02, "chris clepper" cgc@humboldtblvd.com wrote:
pix_video pix_movement pix_blob pix_background etc..
On 4/15/06, Jonathan Goodwin <jonathan@jgoodwin.co.uk mailto:jonathan@jgoodwin.co.uk > wrote: ...some words...
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Jonathan Goodwin a écrit :
Alexandre, this looks like it will be really useful, but I can't get it to work.
It works in the example patch, and if I run my patch and the example patch at the same time then it works. But if I copy the main [pix_sanp2tex] mechanisms to my patch it doesn't work. The only difference is I'm not trying to draw any geos like spheres like in the example.
I'm trying to grab images from my webcam. I'm guessing I may need to implement some kind of buffer setup, but I'm struggling to understand how that works. What does the help file mean when it speaks of the 'index of the frame in the buffer'?
First, the geo on which you draw the snap texture has to be visible : not hidden. Check its z translation value and/or the apha value of the things over it. I like to put it over the rest but with a [alpha 1] and [color 1 0 1 0.8] for instance.
This objects outputs a snapshot of the Gem window on every bang it receives. Maybe you dont want to bang it on every frame. Look for [metro] or [speedlim]. Look also your frame rate. Maybe you are looking for the Gem object [pix_buffer] which I don't master yet.
-
Alexandre Quessy -
chris clepper -
hard off -
Jonathan Goodwin