Inconsistent frame and DAQ rate

[Shazlan]

Hi,
I have written, LabVIEW 7.0, a code (attached) to read from a DAQ card, 3 Visa's and 2 Firewire cameras. Before I included the cameras, everything worked fine. With the cameras, the performance decreases with time (the longer the acquisition time is, the lesser the frame rate). My questions:
1. How can I optimize the code more, to give me the highest possible frame rate?
2. Is my approach in getting capturing the images an "OK" way, or is there a better way in doing it? This is my first time 'playing' around with IMAQ 1394.
3. I have a hunch that if I save every images once it is in the buffer, instead of capture everything first and save later, would increase the performance. Can this be true?
4. Last, is there a quick and ea
sy way to produce an AVI file from the recorded images? I realize that the elapsed time between the images is different and this cause an additional headache in producing the AVI file.
By the way, the desktop I am using is a P4 2.4 GHz, with 1024 MB of RAM (if I'm not mistaken). I hope what I said make sense here and I highly appreciate all the help I could get 🙂 Thanks!

Shazlan

[Bates]

Shazlan,

The first thing you can do to optimize your code would be to use only one IMAQ create. In your code the IMAQ create is inside the loop so you will be using more and more memory as the program runs. I have attach an example with 1394 that I wrote. It has only one IMAQ create. The example also has a implemented a save to AVI for saving the images. I hope this help

A. Talley
Applications Engineering
National Instruments