Transcoding vs. Encoding vs. Transmuxing
- Encoding — converting raw/uncompressed video into a compressed format (H.264, H.265/HEVC, AV1)
- Transcoding — converting already-compressed video from one format/bitrate/resolution to another (e.g., a broadcast 50Mbps H.264 feed → multiple HLS/DASH profiles for OTT delivery)
- Transmuxing — changing the container format without re-encoding (MPEG-TS → MPEG-DASH), which is faster and cheaper but less flexible
For OTT delivery, most operators need full transcoding — multiple output profiles at different resolutions and bitrates — to serve viewers on everything from 4K TVs to mobile data connections.
Cloud Transcoding for IPTV and OTT
Traditional transcoding required on-premise hardware encoders — expensive, fixed-capacity machines that sat idle during off-peak hours. Cloud transcoding replaces hardware with elastic cloud infrastructure:
- Elastic scale — spin up additional capacity in minutes for live events, scale back down automatically
- No hardware investment — pay-per-use vs. six-figure hardware CapEx
- Faster processing — GPU-accelerated cloud transcoding processes VoDfiles dramatically faster than real-time hardware encoders
- Format flexibility — easily add new output profiles (e.g., AV1 for Roku) without hardware changes
Adaptive Bitrate (ABR) Streaming
Adaptive Bitrate (ABR) streaming is the technology that makes modern OTT work at scale. Instead of one fixed-quality stream, the player receives a manifest listing multiple quality options and switches automatically based on the viewer's download speed.
The two dominant ABR formats:
- HLS (HTTP Live Streaming) — Apple's format, required for iOS/Safari, widely supported across all platforms
- MPEG-DASH — the ISO standard format, used by most non-Apple devices and all enterprise DRM workflows
