🟢Apple TV 4K (2017, A10X): H.264/HEVC play at the same power; AV1 and VP9 both cost +29% more — the third silicon-coverage instancev2 · 2026-09-22 (first 2026-08-26)
Device-total W, VLC for tvOS, n=3 per codec across three content families: H.264 4.10 W, HEVC 4.07 W, AV1 5.25 W, VP9 5.28 W — hardware pair (VideoToolbox) flat, software-fallback pair +1.19 W (+29%), gap stable per content (+1.0 to +1.3 W).
🟡Which codec is cheapest to decode has no silicon-independent answer: near-flat on one hardware decoder but resolvable on another, up to ~60% spread in software — and the measurement regime can flip the rankingv2 · 2026-09-22 (first 2026-07-29)
Hw (Google TV): codec spread ≤0.08 W, unresolvable. Hw (Allwinner H618, n=3): H.264 +1.073 > HEVC +0.966 ≈ VP9 +0.971 W — H.264 dearer by 0.107 W, separated (t=4.96). Sw at 1× (both Pis): h264 +1.57 < av1 +1.83 < hevc +2.56 W. Sw saturated: ranking inverts.
🟢A hardware decoder cuts client decode power ~3.7× — and having the silicon isn't enough: stock software must be able to reach it, while having none at all can put the codec out of reach entirelyv2 · 2026-09-22 (first 2026-07-29)
Pi 400, same board, same 1080p60 file — H.264 hw +0.41 W vs sw +1.50 W playing (3.7×, n=6/3); +0.59 vs +2.72 W saturated (4.6×, n=3). Pi 5 (block dropped): +1.57 W.
🟢On modern hardware-decode set-top boxes, an hour of 1080p playback costs ~0.25–0.65 W over the home screen — and the content moves that number more than the codec doesv2 · 2026-09-22 (first 2026-08-16)
Google TV Streamer + Fire TV Stick 4K, 1080p over LAN, 1100–3540 s windows, all 🟢: BBB (animation) +0.60/+0.64/+0.60 W (GTV h264/hevc/av1), +0.59/+0.44/+0.52 W (Fire TV); live-action Meridian/Kranjska +0.25–0.46 W. Codec spread within a content ≤0.1 W; content spread ~0.35 W.
🟢Playing the same video, display attached: THIS fixed-function streaming box draws 4–7× less than a general-purpose board — even against the board's own hardware decoder; a cheaper box is not in the same classv2 · 2026-09-22 (first 2026-07-30)
BBB 1080p60 H.264, local file, screen on, marker-verified: Google TV +0.30 W · Pi 400 hw +1.32 W (4.4×) · Pi 400 sw +1.96 W (6.5×) · Pi 5 sw +2.03 W (6.8×). All 🟢.
🟢Looping a 2-minute excerpt measures the same as playing the continuous original; a 30-second loop does not on every boxv1 · 2026-09-03
Four STBs, one 600 s H.264 1080p60 encode of Big Buck Bunny, n=3 paired passes: its 120 s excerpt ×5 sits within 0.02 W of the continuous 600 s (CIs straddle zero, ±0.03–0.04 W bound on three boxes); its 30 s excerpt ×20 costs the Google TV Streamer +0.012 ±0.009 W and Xiaomi Gen 3 +0.101 ±0.027 W (+3.8 %).
🟢NVIDIA GPU Boost over-clocks the NVENC transcode pipeline into a wasteful zone: ~9-12% more energy for identical encode time and VMAF. Pinning the SM clock removes it — and makes GPU energy reproducible across reboots and ambient temperature.v2 · 2026-08-13 (first 2026-06-20)
h264_nvenc 1080p, Meridian 120s: full boost (SM 2872 MHz) = 0.280 Wh in 12.1 s. Pinned at the knee (SM 2572 MHz) = 0.255 Wh in 12.5 s — 9% less energy, same VMAF, +0.4 s.
🟢On Meridian-120s at the ABR ladder, GPU encodes are 2.0× to 4.4× more energy-efficient than CPU encodes; H.265 GPU produces the lowest-energy file, AV1 GPU the fastestv1 · 2026-05-22
Per-codec ABR · H.264 4 Mbps · H.265 2 Mbps · AV1 1.5 Mbps — most efficient: H.265 GPU (0.30 Wh, 28.4 MB, VMAF 92.0) · fastest: AV1 GPU (15.1 s, 0.32 Wh, VMAF 90.8)