The terms transcoding and encoding are often used interchangeably. We’ve even been known to combine the two here at Bitmovin. For the sake of clarity, let’s define each term:
What is encoding?
Encoding describes the process of converting RAW video into a compressed digital format directly after the video source is captured. Video encoding always occurs early in the streaming workflow. It’s also a must for every broadcast scenario because video content can’t be transmitted across the internet without being shrunk into a more manageable size.
Sometimes the encoder is built into the capture device itself. Other times, it requires a secondary software or hardware encoder for live streaming. With contribution encoding, content distributors generally convert the stream for delivery via RTMP, RTSP, SRT, or another ingest protocol.
What is transcoding?
Transcoding involves taking an encoded stream, decompressing and altering the content in some way, and then compressing it for delivery to end users. Transcoding isn’t always required, but when it is, it occurs after the video source has been encoded.
Transcoding can be done using a live video streaming solution like Bitmovin, a live stream platform like Facebook Live that has transcoding technology built into its infrastructure, or an on-premises streaming server. In common streaming workflows, RTMP-encoded streams are ingested by the transcoder and then repackaged for adaptive bitrate delivery via HLS and DASH. This ensures that the content reaches more users, plays back on more devices, and adapts to viewers’ connectivity constraints.
A simple analogy for transcoding and encoding
Let’s use the gasoline supply chain to better demonstrate the difference between these two live streaming processes.
- First, crude oil is extracted from underground reservoirs. This crude oil can be thought of as the RAW video source itself.
- Next, the crude oil is refined into gasoline for bulk transport via pipelines and barges. This is the encoding stage, where the video source is distilled to its essence for efficient transmission.
- Finally, the gasoline is blended with ethanol and distributed to multiple destinations via tanker trucks. This represents the transcoding step, where the content is altered and packaged for end-user delivery.