The process of converting a video file from one format, codec, or resolution into another so it can be played on different devices and connections.
Video transcoding is the process of taking a video file and re-encoding it into a different format, codec, resolution, or bitrate. It is like translating a document from one language into several others — the content stays the same, but the packaging changes to suit different readers. A raw camera file might be 10 GB, but after transcoding it becomes a set of optimized streams that play smoothly on phones, laptops, and smart TVs alike.
Transcoding starts by decoding the original video — unpacking it from its container format and decompressing the video and audio streams. The raw frames are then re-encoded using a target codec (like H.264 or H.265), at specific resolutions and bitrates. A single upload typically produces multiple renditions: perhaps 360p at 800 kbps, 720p at 2.5 Mbps, and 1080p at 5 Mbps.
These renditions are then packaged into a streaming format like HLS, where each rendition is split into small segments. The result is a set of files that an adaptive player can switch between based on the viewer's connection speed.
Transcoding is computationally expensive. A one-hour video can take anywhere from minutes to hours to process depending on the resolution, codec, and the platform's infrastructure. Some platforms charge per minute of video transcoded, which can make costs unpredictable for teams that upload frequently.
Without transcoding, you are limited to serving the exact file you uploaded. If someone on a slow mobile connection tries to stream a 4K file, they will experience constant buffering. If you uploaded a format that Safari does not support, those viewers get nothing at all.
Automatic transcoding removes this problem entirely. Every video is optimized for every device and connection speed, which means better playback quality, fewer support issues, and no manual work preparing files for the web.
host.video automatically transcodes every upload into multiple HLS quality levels with no per-minute fees. You upload once, and the platform handles the rest — including generating thumbnails, chapters, and subtitles from the content.