since there is no man pages associated with the openRTSP program ,
and the documentaion is only available at the developper website at : http://www.live555.com/openRTSP/
i copied the content of the webpage just in case the website went offline :
-4 output a ‘.mp4’-format file (to ‘stdout’, unless the “-P ” option is also given)
-a play only the audio stream (to ‘stdout’, unless the “-P ” option is also given)
-A specify the static RTP payload format number of the audio codec to request from the server (“playSIP” only)
-b change the output file buffer size
-B change the input network socket buffer size
-c play continuously
-C Explicitly ask for a multicast stream even if the server’s “DESCRIBE” response doesn’t specift a multicast address. (Note that not all servers will support this.) (“openRTSP” only)
-d specify an explicit duration
-D specify a maximum period of inactivity to wait before exiting
-E request that the server end streaming at the specified absolute time (format: “YYYYMMDDTHHMMSSZ” or “YYYYMMDDTHHMMSS.Z”) (used only with -U
-f specify the video frame rate (used only with “-q”, “-4”, or “-i”)
-F specify a prefix for each output file name
-g specify a user agent name to use in outgoing requests
-h specify the video image height (used only with “-q”, “-4”, or “-i”)
-H output a QuickTime ‘hint track’ for each audio/video track (used only with “-q” or “-4”)
-i output a ‘.avi’-format file (to ‘stdout’, unless the “-P ” option is also given)
-I specify a particular network interface on which to receive data
-k specify a user name and password that’s required to authenticate an incoming “REGISTER” command (used with “-R” only)
-K Periodically send a RTSP “OPTIONS” command, to keep the connection alive. (This is useful with buggy servers that don’t listen to our periodic RTCP “RR” packets instead.)
-l try to compensate for packet losses (used only with “-q”, “-4”, or “-i”)
-m output each incoming frame into a separate file
-M specify the MIME subtype of a dynamic RTP payload format for the audio codec to request from the server (“playSIP” only)
-n be notified when RTP data packets start arriving
-o request the server’s command options, without sending “DESCRIBE” (“openRTSP” only)
-O don’t request the server’s command options; just send “DESCRIBE” (“openRTSP” only)
-p specify the client port number(s)
-P write new output files every seconds
-q output a QuickTime ‘.mov’-format file (to ‘stdout’, unless the “-P ” option is also given)
-Q output ‘QOS’ statistics about the data stream (when the program exits)
-r play the RTP streams, but don’t receive them ourself
-R (or -R ) Waits for an incoming “REGISTER” command, specifying a “rtsp://” URL to play. This option is used instead of a “rtsp://” URL on the command line. (“openRTSP” only)
-s request that the server seek to the specified time (in seconds) before streaming
-S assume a simple RTP payload format (skipping over a special header of the specified size)
-t stream RTP/RTCP data over TCP, rather than (the usual) UDP. (“openRTSP” only)
-T like “-t”, except using RTSP-over-HTTP tunneling. (“openRTSP” only)
-u specify a user name and password for digest authentication
-U request that the server seek to the specified absolute time (format: “YYYYMMDDTHHMMSSZ” or “YYYYMMDDTHHMMSS.Z”) before streaming
-v play only the video stream (to ‘stdout’, unless the “-P ” option is also given)
-V print less verbose diagnostic output
-w specify the video image width (used only with “-q”, “-4”, or “-i”)
-y try to synchronize the audio and video tracks (used only with “-q” or “-4”)
-z request that the server scale the stream (fast-forward, slow, or reverse play)