If you can check then there are many free published RTSP DirectShow Source Filters for commercial use with full source code in C++ and I took a lot of time to find them out. But the best out of that one is the source code for VLC and pull out the files:
access.c
real.c
rtsp.c
rtsp.h
That is all you need. When you check the sample microsoft has for a source filter for DirectShow and add these files and complie it then you will get a DirectShow Source Filter that will play any RTSP stream.
Bookmarks