As mentioned, one can run VLC or ffmpeg. I do not know exactly the commands to use them, so I'll give you a third option: GStreamer
Make sure your OS has some installation package for GStreamer (I believe you do not have it for OS / X), if not you can install it by downloading from the URL below:
link
At a terminal, you can test whether your system can decode the RTSP stream using:
gst-launch-1.0 playbin uri="<url do stream>"
If you run correctly then all right. Otherwise, it may be that the version you installed does not support the format used or you ran into a bug. You can report on link
Having executed correctly, you now need to transcode to HLS
gst-launch-1.0 uridecodebin uri="<url do stream>" name=d ! queue ! videoconvert ! x264enc ! h264parse ! queue ! mpegtsmux name=mux ! hlssink d. ! queue ! audioconvert ! faac ! queue ! mux.
You can use gst-inspect-1.0 hlssink to see some properties you can add to hlssink and configure the HLS playlist location and other details if you want. The default will be that the files for HLS will be placed in the folder where you execute the command.
Now you need to run an HTTP server to serve the generated files. The simplest would be:
python -m SimpleHTTPServer
and will start a server on port 8000, then you just need to point the client to link
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