Industrial Vision / Imaging FAQ

1. Are Unibrain’s Fire-i™ drivers compatible with DirectShow?
   Yes. But DirectShow does not support the control of all official IIDC 1394 camera functions. For those functions, Unibrain has therefore provided proprietary replacement interfaces. A detailed explanation is provided in the following downloadable document .
2. What is the best recommended application programming method for the developer of an imaging application?
   Unibrain Fire-iAPI™ provides a C++ class (FiCamera) that abstracts most of DirectShow programming and offers an easy access to Fire-i™ drivers. Its use will avoid the user all the intricacies of COM and DirectShow interface programming.
3. How can I best handle multiple cameras with Unibrain’s Fire-i™ application ?
   Depending on your 1394 networking configuration and on your system resources, Unibrain’s Fire-i™ application and corresponding Fire-iAPI™ can handle multiple cameras for control, display and picture recording.
   Here is how to proceed…

   1. Check for 1394 bandwidth availability
      1. For every camera, you can compute the percentage of isochronous 1394 bandwidth it requires on the bus, and add until an absolute maximum of 100%, using the following downloadable document
      2. check for the maximum number of receive DMA channels of your 1394 interface. One channel is needed by camera
      3. Should you run out of bandwidth or DMA channels, you can add another 1394 interface to your system. It will create a new 1394 bus. The Fire-i™ application will handle transparently all connected cameras, even spread on different busses
      4. If you have other uses of FireWire, like for networking (FireNet™) or SBP2 (external FireWire Hard Disks), DO NOT CONNECT on the same interface board as used for cameras
   2. Check that your PCI bus will never overload, considering your other system loads. Consider 40 Mbytes/s additional load per 1394 interface used for cameras, taken out of the total of 133 Mbytes/s (typical 33MHz 32 bits PCI)
      1. If you display the camera pictures, avoid PCI-type Graphic Display Adapters, you will double the PCI load
      2. If you record live picture on an archive resource, these should best not be interfaced through the PCI bus. This applies also for FireWire networking or FireWire external hard disks. If you do anyway, you must confirm that the PCI bus can accept the additional bandwidth of the streaming data transfer
   3. Reduce the processor load. Some easy rules improve significantly the system behavior, allowing you to handle more cameras
      1. Best display the live preview in default format on screen. Fire-i™ viewer windows allows you any resizing including full screen mode, but at the cost of processor computation
      2. Use overlay. At least one (and for some GDA, 2) camera can be displayed in overlay. Availability of overlay depends on your Graphic Adapter, and on its setting for resolution and refresh rate. 60 Hz refresh rate usually helps for overlay capability
      3. Optimize you Display Color Depth. You can reduce the load by appropriate selection between 16 bits and 32 bits color display
      4. If you need a live display only for monitoring purposes, Fire-i™ application offer an option to replace the camera icon by a miniature live picture
      5. If you record live picture, be aware that selecting a picture compressor may significantly load your processor. You gain on Hard Disk space, but you loose on performance
   4. For live recording, optimize your Hard Disk access
      1. Use the Fire-i™ option to preallocate the recording space. This will create a continuous unfragmented zone on the Hard Disk and avoid loosing any frames
      2. In case of multiple recordings, best use (if possible) multiple hard disks
4. Where can I find a driver for Linux?
   The official 1394 driver can be found at http://www.linux1394.org
5. Where can I find a list with all supported cameras for Linux?
   A complete official camera list can be found at

   http://www.tele.ucl.ac.be/PEOPLE/DOUXCHAMPS/ieee1394/cameras/
6. Is it possible to extend the maximum exposure of Fire-i digital camera / Fire-i board camera, beyond the 33 msec?
   Fire-I Board cameras and Fire-I digital cameras support by default, and due to hardware limitation - a maximum exposure of 33 msec and a minimum of 292usecs.
   If you are interested in astronomy and want to use the cameras for this kind of purpose, a bigger maximum exposure value is required.
   The following web page describes the way to do this through hardware tweaking of the camera:
   http://homepage.ntlworld.com/molyned/web-cameras.htm
7. I have noticed that 1st bit in each frame captured from Fire-i board camera in Y-mono is always zero. Is this a software or hardware problem?
   This is a hardware issue, actually a bug of the TI TSB15LV01 chipset, on which the Fire-i board cameras are based.
   What happens is that Bit 1 is always zero (dead bit).
   Texas Instruments is aware of this issue, but they are not planning to fix it since this chipset is intended for low cost cameras and even with 128 shades of grey, instead of 256, the image is shown properly and the camera can be used perfectly for machine inspection, image analysis etc.