Sometimes you need to calculate the bitrate (in kbps) of a live stream to restrict the usage or manage to the bill of the user. As of today, there is no direct way to get the bitrate of a live stream in Red5 open source or Red5 Pro. Instead, you can use this old-school sampling technique to estimate the bitrate of a live stream which can be coded in any language for any platform.
The steps involved in evaluating the bitrate cab roughly be written as in the following manner :
On application startup, start a timer which will be running continuously (every 2 seconds), aiding in evaluation of bitrates of all candidate streams taken fro a list.
Detect publish start for a new stream
On publish start add the stream to a list as a candidate for evaluation
For each evaluation cycle inside the timer calculate the current estimated bitrate using bytes-transferred-inwards data
Store the evaluated bitrate sample in a tmp data structure. In the similar way capture about 4 or 6 data samples.
Take the average of all the data samples collected to get a average bitrate
Finally use this average bitrate data to calculate bitrate per second.
On unpublish remove the stream from list of candidates so that we dont get a NullPointerException
The code snippet below demonstrates how to calculate and log the average bitrate of a live stream in Red5.
Often we see ourselves troubled by latency issues in live streaming. There are several options to reduce latency…starting from finetuning broadcast settings to switching protocols. Irrespective of the steps taken, it is sometimes preferable to evaluate the latency in a simple way that is admissible to our eyes. In this video, we see how to use embedded timecodes to evaluate actual real-time latency in a live stream. <!–more–>Such testing is encouraged during development stages but might not be best for production.
The diagram shown above is an abstract representation of how a connection flows through Red5 core. On connection attempt, Red5 verifies the basic protocol specific handshake as per the connection type (RTMP/RTSP/WebRTC).
Once the handshake is verified Red5 pro translates the connection to a registered Red5 pro connection and sets a reference to it using the static method – Red5.setConnectionLocal(IConnection) in the context of the current thread.
This article discusses the issue of stream security for subscribers over the various protocols supported by Red5pro (RTMP, RTSP and WebRTC) programmatically. IF you are new to the world of Red5/Red5Pro, I would suggest taking a peek at the Red5 development series on Github. Here you can find information ranging from what is Red5 to how to create and debug an application.