How to control IP Video Source JPEG video filter from C# programmatically

User’s question about Alax.Info IP Video Source DirectShow filter for JPEG/M-JPEG video:

As it stands now, in order to configure the video capture source filter, I have to instantiate it […], set the properties (camera URL, and video dimensions), then save the filter state to a data array which is then compiled into the application. That doesn’t provide a feasible system for user configuration at run time: Telling our customers we need to have the IP address(es) of their camera(s) so we can build a custom version of our software for them isn’t going to be very marketable.


I looked on the Alax.Info Web site, and didn’t see anything that looks like an API for configuration. I also didn’t see anything inside […] that looks like configuration parameters. I find it hard to believe this isn’t a common requirement, so I suspect I’m overlooking something.

Is there an “easy” way to configure the parameters of the video capture filter at run time? Where is it documented?

Is there a structure that describes the state info that is captured [into raw configuration data array]?

Are there any other considerations I’ve overlooked?

C++ and C# sample code (Trac, SVN) appears to be not easy no discover. The code snippets include PlayJpegLocation (C++) and PlayJpegLocationSharp (C#) projects/snippets demonstrating import of IP Video Source COM interfaces via COM and use them from code.

IP Video Source comes with a COM type library which is well suited for import by development environments, specifically by Visual Studio as a reference for .NET projects. To avoid bitness issues, it is recommended to have both 32 and 64 bit versions of IP Video Source installed.

C# integration is straightforward:

First, one needs to add a reference to AlaxInfoIpVideoSource type library, the same way DirectShow.NET is added to the project. The type library is imported and is available via .NET COM Interop at this point (specifically, visible in Object Browser). In code, the definitions are in AlaxInfoIpVideoSource namespace, JpegVideoSourceFilter represents a filter class, with IJpegVideoSourceFilter interface offering filter configuration.

The filter is also compatible with generic COM persistence: it implements standard IPersistStream, IPersistStreamInit, IPersistPropertyBag and other interfaces, its state can be saved to stream or property bad and loaded back.

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