transcode

Transcode, in digital media, is the process of converting a media file from one encoding to another. This typically involves changing the video codec (for example, from H.264 to H.265 or AV1), the audio codec (such as AAC to Opus), the container format, or adjustments to resolution, frame rate, or bitrate. Transcoding usually requires decoding the original stream and re-encoding it with the target settings; in some cases only re-packaging (transmuxing) is needed when the data remains in the same encoded form but uses a different container.

Common use cases include adapting content for devices with limited bandwidth or processing power, distributing media to platforms with specific format requirements, and enabling multiple output profiles for streaming. In live or on-demand workflows, transcoding enables simultaneous outputs at different resolutions and bitrates to match viewers’ network conditions.

Quality and efficiency depend on the chosen codecs, settings, and hardware. Transcoding is typically lossy, with some quality loss compared to the source, and results depend on bitrate, two-pass encoding, and color space handling. Hardware acceleration (such as GPUs and dedicated encoders) can speed up processing but may constrain feature support.

Popular tools range from open-source options like FFmpeg to GUI applications and professional media pipelines. Users should be mindful of licensing implications for certain codecs and of potential latency in live transcoding.