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tseeholzer21
02-15-2006, 06:04 AM
Dear Warrick

A fairly recent PC is able to capture 6 DV cameras without dropping any
frames.
Each camera has a data rate of 3.5 MB/s, so 5 or 6 cameras add up to ~ 20
MB/s.
It is no problem to save this amount of data directly to hard disk.
(writing to system memory should work as well and 1 GB of memory should be
enough for almost a minute of capturing)

I have no experience with Matlab, but our CONTEMPLAS
video analysis software (see www.contemplas.com?id=3)
is able to do that using standard Direct-X functionality which is part of
Microsoft Windows. You do not need any additional drivers or codecs to play
the resulting AVI files on any PC (full resolution, full frame rate).
Video capture is automatically synchronized for all cameras.

Further information: www.highspeed-video.com

Regards,

Thomas Seeholzer
Contemplas GmbH
+49 (08133) 918295
seeholzer@contemplas.com
www.contemplas.com


> -----Ursprüngliche Nachricht-----
> Von: * Biomechanics and Movement Science listserver
> [mailto:BIOMCH-L@NIC.SURFNET.NL] Im Auftrag von Warrick
> Gesendet: Mittwoch, 15. Februar 2006 15:56
> An: BIOMCH-L@NIC.SURFNET.NL
> Betreff: [BIOMCH-L] Video capture and memory limitations
>
> Dear List Members
>
> Like many others, we are looking into setting up a low cost
> kinematics lab
> (specifically for human whole body motion analysis).
>
> We are currently investigating whether Matlab can be used to
> capture images
> from 5 digital cameras (cheap commercial miniDV cams),
> connected to Pinnacle
> video capture boards (firewire 400Mbps). Currently we are only able to
> capture about 100 frames (720 x 576pixels) before we encounter memory
> problems, using a fairly fast PC (3.8GHz, 2Gb RAM).
>
> I would therefore like to enquire whether anyone has
> encountered a similar
> problem and has either found a solution using Matlab, or
> using some other
> video capture software (preferable software that enables
> access to video
> file from other applications).
>
> Thanks in advance
>
>
> -Warrick
>
>
>
> --------------------------------------------
> Warrick McKinon
> Exercise Laboratory
> School of Physiology
> Wits Medical School
> South Africa
>
>