Setup for a live (low-latency) audio video broadcast over Wi-Fi?
The Upgrade
We are capturing audio (from mixer) and video (from a camera) from a main auditorium and passing it to separate rooms within the building.
We used to have done this via manual audio/video cables and wires (eg. RCA, CoAx, not Ethernet). We wanted to "upgrade" the system and wirelessly broadcast the stream via Wi-Fi.
The Problem
In our current setup (Wirecast running on A10 on a Wireless-N network), we have the problem of delay. Our streams are delayed from a minute up to five minutes on the clients (laptop/iPad/Android). These kinds of latency problems arise from the box setup, not really whether LAN or WLAN is used.
This had not been a problem from the previous wired connections. Since the wireless network is local, we thought that a delay of less than a second should be achievable.
Our Question
And so it goes. Anybody there who has any experience for a setup that has both low latency and at the same time user-friendly to clients streaming in the program? Any recommendations would be highly appreciated.
We have already tried VLC to broadcast the live streaming, but there is the problem with latency. On a local computer "stream" without encoding, VLC has about a second of delay already. Add encoding and the local network, then the situation looks more bleak. We would like to achieve at least 1 second of delay.
(Our current setup in on Windows 7, but setup on a dedicated Linux box is preferred, if achievable.)
According to the tests I realized this week with wired network between a RaspiberryPi (with Raspicam) and my laptop, Gstreamer has better performance and less latency than VLC. I had around 1sec delay with VLC, and it was not constant, sometimes the video slows down and sometimes it accelerates.
With Gstreamer I can stream a HD video (1280x720 @ 60Hz) with a measured delay of 100 to 116ms. I tested it on Ubuntu 14.10 with Gstreamer-0.10. It also works with Gstreamer-1.0 but I need to work with 0.10 because of incompatibilities with v4l2loopback.
Some users reports good performance with MacOS and Windows too.
For a tutorial about this on Windows see http://robogoby.blogspot.fr/2014/01/raspi-camera-gstreamer-10-w-windows-7.html
For video and audio streaming with gstreamer you can see this : http://blog.tkjelectronics.dk/2013/06/how-to-stream-video-and-audio-from-a-raspberry-pi-with-no-latency/
hope this help.
Cheers
You guys may be interested in implementing a VLC (Video Lan Client) solution for this. It is available on many operating systems including Linux. Their home page is here VideoLAN VLC. A good tutorial for setting up live streaming via the software can be found here. Live Streaming: How to Use the Technology. By putting two and two together you will be able to install the VLC software on to a Linux computer and set up your devices to capture so long as everything works out according to plan. It is at least worth a shot at trying.
Thanks,
Sean W.