I have an application that works with three USB cameras (DirectShow devices), and for each camera I would like to implement a process. When I try to put more than one application control component, I don't see the devices at all: I can only see them when I use one application control. When I try to add more than one Acquisition component, I don't see the devices. What is the best way to work with three cameras and for each camera other processes?
The HSAcquisitionDevice is a special process. Instead of having one per camera, you only need one to manage all three cameras. The reason why it has been designed this way is to have better control over the acquisition process; for example, it allows the asynchronous triggering of different cameras while not being dependant on the others, and it simplifies the capture waiting process.
However, to make this work, the HSAcquisitionDevice needs a lock on all devices, rendering any other instance of HSAcquisitionDevice useless (emulation only).
For more information see Using Multiple Configurations, in the HSAcquisitionDevice section in the user guide.