The telecommunications industry has changed dramatically in a decade and no one knows how it will change in the future.
Although we are using transcoding at the current time, we hardly think about its underlying functionality. Unlike the normal definition, transcoding is a little different in VoIP calling. To put it simply, it is the transformation from one voice type or codec to another.
We will discuss the role of transcoding in the telecommunication business. Along with that, we will give you a total overview, including the work process of transcoding, its types, and many more.
In order to increase the compatibility of a media file for a number of target devices, a process is needed to convert a video or audio file from an encoding format to another. This process is called transcoding.
Just like the transmuxing process, FFmpeg can be used for transcoding. FFmpeg is an open-source platform for handling both audio, video formats. With a simple command like below, a media file can be converted to a standard H.264 mp4 format.
ffmpeg -i "sourceVid.mov" "transcodedVid.mp4"
Although setting up a specific resolution using the FFmpeg requires complete knowledge of the software, the following command is enough to do the task –
ffmpeg -i rtmp://server.ip/app/1080 -vcodec libx264 -preset veryfast -x264opts nal-hrd=cbr:force-cfr=1:keyint=60 -b:v 3000k -maxrate 3000k -bufsize 3000k -s 1280720 -sws_flags spline -r 30 -acodec copy -f flv rtmp://server.ip/app/720Command
The above command includes several factors like buffer, bitrate, resolution, and framerate in the output. The command uses the x264, an H.264 encoder, and takes an RTMP stream. The final output of the file remains in an FLV format.
Large streaming organizations like Twitch use both FFmpeg and their own TwitchTranscoder to stream audio and videos. This is a great example of transcoding.
On the other hand, YouTube uses transcoding to make videos available in more than 5 formats and qualities. And you will be surprised to know –
-Uploads of more than 300 hours are received within one minute by Youtube
YouTube will start the encoding and transcoding process immediately after the original video is uploaded. It means, more than 20 versions can be transcoded after the original content is uploaded. That’s why users first get low-resolution videos until the high-resolution videos are transcoded.
Transcoding in the telecommunications industry is the process of converting a media stream from one codec to another. This is done to overcome the difference in the ability of the telecommunications system to support the caller and the receiver.
In telecommunication services, there are situations where transcoding is very difficult. When the two endpoints in the call share different codecs remaining in their codec sets, this type of situation can occur.
In addition, if the end-party only supports the G.723 codec and the originating end supports the G.729 codec, the call audio will no longer work in a direction unless the VoIP provider transcodes between these codecs.
Session Border Controller (SBC) is a commonplace to perform transcoding. But be aware of choosing a valid or invalid SBC because transcoding is not supported by all SBCs.
Transcoding deals with the data that are already encoded. While encoding is a natural lossy process where a certain amount of data will be lost ultimately affecting the quality of the audio and video. Lossless compression can be used for encoding, but this leads to lower compression ratios and larger media formats.
Mainly three types of transcoding are used in the telecom business –
Lost data and quality can’t be recovered during the transcoding or encoding process as there is no such thing as lossy-to-lossless transcoding.
The Session Border Controller or SBC is a dedicated network element on SIP-based VoIP infrastructure. It mainly helps to manage real-time communication sessions. SBC not only provides complete control over the session but also hides the internal network from the outside world. Although the focus is on the software version, SBC can be found in both hardware and software forms.
For telecom business, WD Telecom offers decent functions to handle multiple codecs and perform automatic transcoding when required. AMR, G711, G729 are the most popular codecs in IP telecommunication. And WD Telecom has the built-in functionality that perfectly supports them.
The role of transcoding in the telecom business can lead to both success and failure unless you fail to determine the correct SBC. There are many codecs iLBC, G.711, G.726, G.722, G.723.1, AMR, etc. But not all are supported to be transcoded with SBC.
We have already mentioned in this article, to pay attention to choose a suitable SBC as not all are competent for transcoding. And you may never know the number of compatible SBCs by asking. Rather, it is better to make a list of codecs that works flawlessly with SBC.