Netflix has announced that it will reduce the bitrate of its video streams in South Africa to help ease congestions on local networks.
Congestion on local networks has a higher chance of taking place as more people use Netflix and other streaming services during the 21-day lockdown imposed by the government to combat the outbreak of the COVID-19 coronavirus.
The streaming service said it will reduce its bitrate across South Africa and Africa after 23:59 on 30 March 2020. This will last for 30 days.
Netflix said it would be able to maintain its video quality, however, while reducing traffic by 25% on local networks.
“Given the crisis, we’ve developed a way to reduce Netflix’s traffic on telecommunications networks by 25% while also maintaining the quality of our service,” Netflix said.
“So consumers should continue to get the quality that comes with their plan – whether it’s Ultra-High, High, or Standard Definition.”
In this case, the “quality” metric referred to is the resolution of the stream – but a reduction in bitrate can impact other aspects of a video stream’s performance.
What is bitrate?
Firstly, the term “bitrate” refers to the number of bits per second transmitted through a network.
In the context of streaming services like Netflix, a higher bitrate accommodates better video quality – as more data is streamed to the viewer per second.
Reducing the bitrate of a stream means that less information can be transmitted to the viewer, although this does not necessarily mean the resolution of the video is lowered.
By changing the colour depth, framerate, audio quality, removing HDR support, or using codecs with more aggressive compression, the bitrate of a streamed video can be reduced without changing its resolution.
As Netflix’s subscriptions are tiered by, among several elements, maximum resolution, it has therefore used methods other than reducing streaming resolutions to reduce the bitrate of its videos.
Slight drop in quality
In a media statement regarding the reduction of streaming bitrate in Europe, Netflix said the changes it has made would result in a slight drop in quality for discerning viewers.
As the streaming service is implementing the same bitrate reduction measures locally, South Africans may note a small drop in video quality across all resolutions – although the difference should be minor.
“In normal circumstances, we have many (sometimes dozens) of different streams for a single title within each resolution,” Netflix said. For the next 30 days, within each category Netflix has removed the highest bandwidth streams.
“If you are particularly tuned into video quality you may notice a very slight decrease in quality within each resolution. But you will still get the video quality you paid for.”
MyBroadband asked Netflix what video data has been removed with the highest-bandwidth streams, but the company did not respond by the time of publication.
Netflix also has other measures in place which reduce the load on local ISPs and their networks.
The company provides ISPs with Netflix caches (servers with Netflix content on them) to install on their networks for free, and they have thousands of these caches installed at 3,800 locations in 143 countries around the world.
These significantly reduce the load on telecommunications networks and improve the viewing experience thanks to lower latencies and less buffering.
Netflix only updates these caches with new content during off-peak hours to reduce the impact on viewers.