Relate image and data

[Liepo]

Hi there,

I am still learning to program in LabView, and I need to create a program that will acquire data from 2 cameras and a spectrophotometer. 

1. Using a simple GRAB VI i am not being able to save a new image, just overwrite existing ones. Why is that? 

2. How should I program it so that the 3 datas will be acquired at the same time? Does it has something to do with sequencial/parallel programming?

3. The cameras should be triggered together and with the same interval as the spectrophotometer`s readings, and the datas need to be indexed in a way they are related. (For example each image from camera 1 is related to an image from camera 2 and to the respective reading of the spectrophotometer)

Which method is good for synchronizing the datas?

I need to save data at 3 times per second. I don`t know if that matters.

Please someone give me a light here, or some related example that I could modify to fit the requeriments of my project.

Thanks in advance,

Liepo

PS:I`m sending the GRAB VI I if you can find out why it is not working the way I expected.

[Abel_Souza]

Hi Liepo,

What LabVIEW Version are you using?

What kind of camera are you using? (USB, GigaE, Camera Link, etc)

Regards,

[Liepo]

Hi, 

thanks for answering!

The camera I`m using is a Point Grey (Flea3 FL3-U3-13E4C) with a USB 3.0 connection. It has a General Purpose I/O that can be connected to an external trigger.The version of LabView I have is 2012, with Vision and IMAQ packs. And in case you are wondering the Spectrophotometer is a USB-2000 from Ocean Optics.

Would you recommend using the external trigger?

PS:Também sou do Brasil, se quiser conversar em português. 

Thanks a lot,

Oscar

[Abel_Souza]

Hi Oscar,

The VI you had attech on the first post was done using IMAQ for USB Cameras, but this driver is to use with LabVIEW 8.6 or previous. Since LabVIEW 2009 We can use USB cameras with IMAQdx functions.

The following link show some ceveats about use multiple USB cameras with LabVIEW.

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000001De1ESAS&l=en-US

This other link have an example using multiple USB Cameras

https://forums.ni.com/t5/Example-Code/Toggle-between-Multiple-USB-Camera/ta-p/3506301

And a tutorial about comunicating with any USB device

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000x1qzCAA&l=en-US

If need a big precision on start time to acquire at the sime time on all cameras and spectrophotometer is a good idea use an external trigger, but if you don´t need much precision you can do trigger by software.

PS: achei melhor responder em inglês pois assim o fórum pode ser útil a outras pessoas do mundo inteiro que possam ter uma dúvida parecida.

Atenciosamente,

[Liepo]

Thank you for the links,

so I have to download this IMAQdx driver? I can't find it nowhere. Do you have a link for it?

Do you think the error is related to this ?

Thanks,

Liepo

[Abel_Souza]

IMAQdx driver is part of Vision Acquisition Software and you can install it from your device drivers DVD or download from the following link.

https://www.ni.com/en/support/downloads/drivers/download.vision-acquisition-software.html#306459

Probably the error is more related with the ceveats to use multiple USB cameras, but IMAQ for USB Cameras never was a official NI product and never had support from NI.

NI IMAQdx was the same driver that work with firewire and GigaE cameras and always was supported by NI and is a more stable driver, but if don´t follow ceveats to use multiple USB cameras we can receive the same error. It occur because many USB cameras is identified as the same cameras by IMAQ.

regards,