How to chose hardware/software?

[velocity160]

Hi,

I have a project  involving vision and I am not sure how to select the right software and hardware.

I need to connect two cameras on a PC. I am planning to buy two simple Fireware cameras, maybe the Guppy F-036 with the following specs:

	Guppy F-036
Pixels (H x V)	752 x 480
Pixel Size (H x V)	6.0 x 6.0µm
Pixel Depth	8 bit
Frame Rate	60 fps
Video Output	IEEE-1394/FireWire
Synchronization	External or Via Software
Exposure Control	Programmable via IEEE-1394 bus

Then I need to analyse the images with the LV Vision toolkit.

I need at least 30 frames/s but 60 fps would be better and I would like to use the maximum resolution available.

I have two options:

1 -record 3 hours of video on the hdd and analyse each frame offline.

2 -analyse the image in real time

I am wondering if I will be able to save or analyse 752x480 pixels images at 60 fps ? (Same processing for two cameras simultaneously.)

The processing consist in finding edges and taking measurements.

Thanks!

[Steverino]

It depends on what you mean by "analyse".

If you are doing something simple like using the light meter (machine vision), then you might get away with it. More complex image processing takes more time.

There is a tool in Vision Assistant that estimates the time it takes to run the IP algorithm. For example, an algorithm I am developing has an estimated time of 756.83ms.

Hope this helps.

Message Edited by Steverino on 10-07-2008 05:31 PM

Message Edited by Steverino on 10-07-2008 05:31 PM

[BruceAmmons]

Finding single edges and measuring should be a pretty quick process.  Finding a horizontal or vertical edge would take longer due to the multiple calls to find edge within each of those.  I like the idea of using Vision Assistant to prototype your application and estimating the time it will take to do the analysis you need to do.

If you are going to analyze images from two cameras at 60 fps each, you will need a fast computer.  I would select a fast dual processor or even a quad processor.  Write your routines in parallel to speed up the analysis.

I don't think you could stream 120 images to disk for very long.  It would take a large amount of space and multiple drives.  You would need something like the new NI disk arrays that can stream data at high rates.

Bruce

[Chris_VH]

velocity160,

As has been previously answered, your processing time will depend heavily on what exactly you are trying to do. I would not recommend recording 120 fps for 3 hours, the amount of hard drive space that would occupy is enormous. It seems that your best option is to analyze the frames in real-time, which is going to rely on your computer's speed and what processing steps you are wanting to do. 60 fps for 2 images is very fast to analyze in real-time, so complex processing would be pretty difficult, but simple processing will be possible in your desired range.

As far as equipment that you will need; you can find our 3 firewire cards here. All of these frame grabbers will come with Vision Acquisition, which will contain IMAQ-dx with it. You will also need Vision Development Module (VDM) to do processing on your images.

I hope these suggestions help you with your setup.

[BruceAmmons]

Another thing to consider - At 60 fps, two cameras will exceed the bandwidth available with a single firewire card.  You will probably need two firewire cards to capture all the images.

Bruce

[velocity160]

Thanks all for your answers. It helped a lot.