[PD] Pd/GEM and camera for tracking

[Jack]

Hello Martin and thanx for your reply,

In fact, i need a camera to track people in a space (indoor). The  
camera will be on the ceiling.
There is 5 meters between the ceiling and the floor.
With the coordinates of people, i will turn on/off differents lamps  
on a statue placed in the center of the space.
So i need a camera working on a MacMini with MacOSX.5 and Pd and GEM.  
The last MacMini has a FireWire 800 and 5 USB 2.0.
I saw the point grey website, but i can't find price on it. However,  
they talk about 10 meters cable for FireWire 800.
Do you know a model and its price ?
Today, I tried a Unibrain Fire-i™ Digital Board Camera and it seems  
good (FireWire 400 : 89 euros + 19 euros with lens) But i never tried  
it in installation.
++

Jack



Le 6 mars 09 à 18:06, Martin Schied a écrit :

> hey all,
>
> Jaime Oliver schrieb:
>> mmh, I don't really know about lengths. I think there is a limit  
>> to how long your firewire cable should be. I usually work with  
>> analog cameras in linux where cables can be long ad I capture with  
>> a pci card.
>>
>> I think a cheap option that I've seen working well with macs is  
>> the unibrain fire-i:
>> http://www.unibrain.com/Products/VisionImg/Fire_i_DC.htm
>>
>> you can buy lenses and chain them, not more than 30fps though,
>>
>> J
> lengths between firewire 400 devices is usually 4.5m, but you can  
> daisy chain them up to 16 times giving you 72 metres. it's not very  
> recommendable to make long chains, as every plug may be a "weak  
> point" in your chain. firewire 800 can have longer cables, but i  
> don't know...
>
> Jack schrieb:
>> Thanx for the reply. The models are too big for me. I need a  
>> smaller camera (something like a cube) because the installation  
>> must be discreet. Have you something else to suggest ?
>> Chris : what do you think about Sony driver ? I can't use a PCI  
>> card because i will work with a macmini.
>> ++
>
> as manufacturer of small firewire cameras there's also "point  
> grey". I don't know exactly about cost, and didn't try them on my  
> own but they often were recommended by people doing tracking, also  
> being said they were affordable, especially the "firefly mv" which  
> delivers 60fps at 640x480 and even higher frame rates at lower  
> resolutions.
>
> that's what they say about macintosh (seems to work):
> http://www.ptgrey.com/support/kb/index.asp?a=4&q=173
>
> i also made tests with usb webcams (only on linux and windows),  
> some with usable results but most of them are crap. to be usable  
> they should support "real" usb2.0 for high frame rates at full  
> sensor resolution (usually 640x480), without compression and have  
> ccd sensors for better quality and light sensitivity. (finding out  
> usb version and other technical stuff can be real pain from  
> manufacruerer sites, usually you'll have to try them).
> image quality was always worse than cheap video cameras - but as an  
> advantage they were not interlaced like usual consumer video  
> cameras. cable lengths can be extended by usb hubs or "repeater"  
> cables several times, but that's also the "many-connectors - many  
> errors" thing
>
> @Jack: what exactly will your tracking method be based on? natural  
> features? colors? markers? with some luck a cheap usb webcam  could  
> be good enough and also really small. (yeah, i'm a fan of using  
> cheap consumer producs and having trouble with them - be warned)
>
> cheers,
> Martin