1 stereo mic linked to a mac
3 ip-cams linked to a modem

I want
to send the 3 videos directly in live-streaming at the same time (in synchr), from the modem to the web,
and also to send the audio-stereo from the mac to the web (in synchro with the videos)

I need
to build a little free-app for clients-only that gives to everybody in internet the possibility to change in real time the video sources from the 3 I offer, but always listening to the audio source without stop it... like a surveillance software or like a virtual direction cabin (also having 60 seconds buffer! I need only synchro between 3 videos and audio).

The question is: what kind of software, or programming language, can I use to obtain this result? I'm a pd newbie, but I'll go for pd if you say to me that it's just for me and can do the job.