how to save a stream on the hard disk by using rtsp in c #

I am currently doing a program with c # that can locally copy the video that is displayed by rtsp protocol, I have tried with VideoLan DotNet for WinForm but it does not save me on the disk even though I pass the options with : sout = # transcode {vcodec = theo, vb = 800, scale = 1, acodec = flac, ab = 128, channels = 2, samplerate = 44100}: std {access = file, mux = ogg, dst = C: \ Users \ hsilva \ Desktop \ 123.mp4}

someone has implemented this kind of solutions that can help me,

thanks.