Acquiring Images From Multiple USB Cameras Simultaneously Using IMAQdx

Solution

You can acquire from multiple USB cameras simultaneously using NI-IMAQdx but there are some important caveats:

Some USB camera drivers are not capable of acquiring from two cameras simultaneously. Since the NI-IMAQdx driver goes through the third-party camera driver, if the camera driver is unable to acquire from multiple cameras simultaneously, then NI-IMAQdx will not be able to acquire from these cameras simultaneously. As there are many varieties of USB cameras on the market, NI is not able to test them all to determine which of them have drivers that are capable of acquiring from two cameras simultaneously. You can try testing out the cameras themselves if you already have the hardware or otherwise try checking with the camera driver's manufacturer to confirm.
Another limitation is the computers USB bus itself. Ensure that your computer can handle the amount of data that will be passed over the bus with multiple acquisitions running at once. If you have several USB devices plugged into your computer, these can take up bandwidth and cause a timeout error. Consider using a different USB port for each camera, to make sure you have enough bandwidth room for each camera.
As these cameras are working with the USB standard, only software-timing (as opposed to hardware-timing) is available.