Yardsticks
A speed figure compared only with our own build says little. Each speed claim on these pages is checked against an independent implementation, named here, and the gaps that check found are listed in the full write-up, worst first.
Which implementation each claim is measured against
| Claim | Yardstick |
|---|---|
| Native encode speed per preset, Arm and x86 | x264, x265, SVT-AV1, libaom, libvpx and openh264 at their real-time settings, timed in the same rounds; NVENC for scale |
| H.264 and HEVC decode | FFmpeg's decoders |
| AV1 decode | dav1d (VideoLAN) |
| VP9 decode | vpxdec (libvpx) and FFmpeg's VP9 decoder |
| VVC decode | VVdeC (Fraunhofer HHI) |
| AV2 decode | avmdec, the research reference decoder (not built for speed) |
| WebAssembly decode and encode | the official single-thread ffmpeg.wasm (a weak yardstick: a generic build without hand-written SIMD, and no AV1 or VVC decoder) |
| Colour conversion and the demo's display path | libyuv |
| Time to the first packet, memory | the same reference encoders and decoders, measured the same way |
Rules of the comparison
- Every decoder and encoder runs with one thread, including the references, which are normally run multi-threaded and are faster that way.
- Runs are interleaved and rotated between rounds on a reserved core of a shared PC, so small differences there are noise; the Jetson runs on one core at a locked clock.
- Our decoders are first checked to produce the same pictures as the reference decoder on every third-party stream used.
- Where no measurement exists, the write-up says so rather than estimating.
Read the measurements
- Speed claims against independent yardsticks: every claim, its yardstick, the measurements and the worst gaps.
- Decoder speed: our decoders against FFmpeg, dav1d, vpxdec, VVdeC and avmdec on the PC and the Jetson.
- Speed: the encode, browser, decoder and hardware tables, generated from the repository's data.
We thank the FFmpeg, dav1d, libvpx, VVdeC, AVM, libyuv, x264, x265, SVT-AV1, libaom and openh264 projects: their implementations are the bar these numbers are held to.