Our client, Cerona Networks Corporation, created a new hardware product, the Cerona XpressVu™ DualTuner PCI Express DVB-S/S2 Card. This is an add-on card for a PC or server that allows one to send information over digital video signals and treat the information as if it were coming over the Internet. Working with their engineering team, we developed several pieces of software to help run the card when installed in servers running Microsoft Windows Server.
The first piece that we developed was a graphic user interface (GUI) used by administrators to monitor the state of the card and configure it (see the screenshot on the right). It is a .NET application written in C# using Visual Studio 2008. This software had several tabs:
- Status: displayed the status of the card and allowed one to select from several stock configurations or manually enter configuration information.
- Config: provides settings that affect the overall behavior of the software, such as the threshold for signal quality below which an error is reported.
- Errors: shows a list of errors as they occur in real time
- About: displays information about the software and Cerona Networks Corporation
The GUI communicates with the card using the Microsoft DirectShow API. However, the DirectShow API cannot be accessed directly from a .NET application, so the code that interacted with DirectShow was written as a library, around which Celtic Wolf then created a managed code wrapper. This wrapper was then called from the GUI, allowing the .NET application to talk to the DirectShow library. The managed code wrapper was written in C# using Visual Studio 2008.
The final piece that we did for this project was a Windows Service. This is a piece of software that is run automatically when the computer is started. It monitors the state of the card to make sure that it still has a signal. If the card loses the signal, the service attempts to retune the card in order to regain the signal so that the data flow will remain uninterrupted. The service writes its activity to a log file so that it can be checked by administrators if needed. This program also uses the managed code wrapper to communicate with the card.
The service was also a .NET application written in C# using Visual Studio 2008.
