Are you wondering what is Plex Transcoding? If your answer is YES then you are in the right place. In this guide, we will discuss everything about Plex Transcoding.
Transcoding in Plex is the most common question asked by new users. Users who recently started using Plex will ask questions like What is Transcoding? Why does a file need to be transcoded? When does a file need to be transcoded? How is a file transcoded?
In this guide, we will answer all of these questions so make sure to read the article completely and understand the actual concept of Transcoding in Plex.
Also Read > How to Install and Setup Plex Media Server
What Is Transcoding?
let’s first understand what is Transcoding. It is a very easy-to-understand concept but it does make your media stream on different devices.
Transcoding is the process of converting a media format into another format so that it can be played by a device. In the case of Plex, the media file will need to be converted because not every device supports every file format.
For example, if you are using Plex on a desktop then you you will be able to play almost every file format because desktops usually have a powerful processor and a graphics card for hardware acceleration.
On the other hand, if you are using Plex to stream media on a mobile device then the media file format will need to be converted into the format that will be supported by the mobile device otherwise you won’t be able to stream.
Why Does Plex Need to Transcode?
As I mentioned earlier, Plex would need to transcode the media file format so that the device can play the file. However, there are three criteria Plex uses to determine whether a file needs to be transcoded.
1. Encoded With A Compatible Codec
In order to play the files device needs to decode the media files associated with the codec which is used to encode the files. If you are using the older version of the device then it can not handle codecs such as x265 (HEVC/H.265). In this case, Plex needs to Transcode the media so that the device will be able to decode the files and play.
2. Encoded with a compatible bitrate
Every device has a different bitrate limit, to play the file your file should be in a supported bitrate. For example, the mobile device usually has a 10 Mbps bitrate limit to play files higher than 10 Mbps, so Plex needs to transcode the file.
3. Contains a compatible resolution
Similar to bitrate every device supports specific video resolution. To play media files the resolution should be in the supported resolution otherwise Plex would transcode that video to a supported resolution.
These are three criteria that will help Plex decide whether the files will need to be transcoded or not. If the media file does not fit any of these criteria then Plex will transcode the file to supported format.
How Does Plex Transcode?
Now you know what is transcoding in Plex and why Plex needs to transcode the media files, it’s time to look at how it actually works in the background.
Whenever the client requests to play the files, Plex will gather the information such as container, video encoding, audio encodings, bitrate, and resolution and store it in the Plex database.
Now before starting to play the media file, Plex will identify the client device compatibility whether through the client profile or by using the quality settings sent by the client.
After knowing all these things Plex will determine if the file can be directly played, or directly streamed, and it needs to be transcoded.
After that Plex uses the decoders to decode the file and then uses the encoder to transcode and stream into a compatible file format for a device.
The transcoding process will be done into a chunk and sent to the client’s device. The speed of the transcoding process can be determined by whether Plex uses the CPU or GPU to transcode the file.
If Plex uses the CPU to transcode the file then it will show down the server and may be unable to transcode because the transcoding process requires a huge amount of resources.
If Plex uses the GPU then you will be able to transcode multiple files by using the graphics card in the server. Plex transcodes the file in a chunk and sends it to the client’s device.
Once the user stops streaming all of these transcoded chunks will be deleted automatically.
I think that’s all you need to know about what is transcoding in Plex. For detailed information and a better understanding of Transcoding refer to this video on YouTube: