[PD-dev] Fwd: PureData/Gridflow/Camera

Mathieu Bouchard matju at artengine.ca
Tue Aug 4 23:38:56 CEST 2009

On Sun, 2 Aug 2009, sisil mehta wrote:

> Actually i'm a newb... i had some of the following questions: for using 
> the camera do i need to add some path to the file->path section?

does the [#camera] object create? GridFlow adds two hidden lines to the 
file->path section, as soon as -lib gridflow is really loaded (without any 
"undefined symbol").

> do i need to change over to pwc? or keep using v4l?

"pwc" itself is a driver, whereas "v4l1" and "v4l2" are protocols. the 
"pwc" driver talks with an app using "v4l1". there are some pwc-specific 
options in the [#camera] patch, which you can enable using the pwc toggle, 
but only if you know that the driver is pwc. don't try using the pwc 
options of [#camera] with cameras that don't go thru the pwc driver.

> which one is required for webcam, mine is :creative integrated webcam.

Well, if you want to know which driver is being loaded for your camera, 
try this command:

   lsmod | grep videodev

in my case, this shows:

   videodev               33408  1 pwc
   v4l1_compat            13700  1 videodev

which means: videodev is a driver used by the pwc driver, and v4l1_compat 
is a driver used by the videodev driver. in the videodev line, you should 
have the drivers for any usb cameras you are using at the moment, plus 
drivers for any pci cards and pc-cards you have for that (TV input cards, 

> Ultimately i need to use #labeling , but i cant even find it...i have 
> the newest version of gridflow.

this is a separate issue. or two. first, you can test [#labeling] without 
a camera, so you can fix your camera problems separately from your 

BTW, if you use the gridflow cvs, please consider switching to the 
gridflow svn. I'm thinking about shutting down the gridflow cvs to make 
sure people who want the most recent gridflow don't trick themselves 
into thinking the cvs is the most recent. basically, I have replaced 
cvs by svn, but I left the cvs there just in case.

  _ _ __ ___ _____ ________ _____________ _____________________ ...
| Mathieu Bouchard - tél:+1.514.383.3801, Montréal, Québec

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