Write to file(AVI) synchronizate data

[beszabo]

I receive a USB Camera signal and a CAN(Control Area Network) signal.

I like two signal parallel displaying and write to file (one or more) and after read.

I practise IMAQ AVI Write Frame.vi with DATA.

I receive USB Camera signal around 15fps (but this is not constant). Two CAN messages receive 10ms/sec.

(200 CAN messages per sec -> 1camera signal/14 messages: I make a queue. When receive a Camera signal, than in all queue data associated with the image to write).

I make two loop:

First: read USB Camera and save AVI with data

Second: read CAN messages

My problem is bottleneck CAN bus?

(webcam_can2.vi)

[Dippi]

Hi beszabo,

I don't really see, where your problem is.
Perhaps you could be a bit more precisly, so that we can better understand your problem and find a solution.

Best regards
Dippi

[beszabo]

Thanks Answer!

It is very interesting, when I use Webcamera (Logitech Quickcam PRO 9000), 320x280 around 15 fps, and receive CAN messages and take my hand before Webcamera (darkness picture, not full dark), then CAN messages coming slow (200 messages/sec in place of 5- 10 messages/sec).

[HIDIR]

Hi

http://forums.ni.com/attachments/ni/170/281385/1/CAN_AVI.llb has the CAN_AVI.llb The "webcam_can2.vi" is included in the library.

After opening it the error about the "wecanusb.dll" appears. How can I use this VI.How to fix this error?How can I find wecanusb.dll or should I write it by myself?

Could you help me please? OR can I find any VI to analyse the video and get the acceleration information?

I am looking forward to hearing from u. Thank you

[HIDIR]

Hi

For the VI in the attachment (from the CAN_AVI.llb) the problematic part is the  " call library function node" which is defined as the wecanusb.dll.

What should be done ? How the input parameters should be processed to be outputted by the " call library function node"  block  ?

thank you..

Message Edited by HIDIR on 04-23-2009 03:43 PM

Message Edited by HIDIR on 04-23-2009 03:44 PM

Message Edited by HIDIR on 04-23-2009 03:47 PM

[Candan]

Hello Hidir,

You can always call our NI Turkey office (www.ni.com/turkey) for a faster reply.

Basically, the Call Library Function Node calls the missing wecanusb.dll file (this file should locally stored on your computer). The input and output parameters could be anything, specified by the programmer that created this .dll file.

So, in order to process this (or any) .dll file, you must have some explanation (input/output parameters, function prototype etc.) for the .dll file itself. But one question to ask for is "why do you need this .dll" ? You may use some other image acquisition options (http://www.ni.com/vision/).

Regards;

Candan Caner
Applications Engineer // National Instruments Turkey // (+90) 212 279 3031 // candan.caner@ni.com