Glossary

Glossary

Terms that appear in TinyPPI's overlay, settings and this wiki.

Term	Meaning
Amlogic	The SoC maker whose chips power most CoreELEC boxes. TinyPPI reads the Amlogic video driver for display mode, pixel format and EOTF, and writes its Dolby Vision driver for VS10.
Aspect ratio (visible)	The ratio of the picture inside the black bars, computed from L5 offsets — unlike Kodi's value, which describes the coded frame.
BL	Base layer — the backward-compatible video layer of a Dolby Vision stream (HDR10, SDR or none).
CLL / MaxCLL	Maximum Content Light Level — the brightest pixel of the whole title, in cd/m².
CM version	Content Mapping version of the Dolby Vision display-management metadata: CMv2.9 or CMv4.0 (which adds L3, L8–L11).
Composer	The part of the RPU that tells the decoder how to reshape the base layer (and combine the enhancement layer) into the Dolby Vision picture.
CoreELEC	A Kodi-centric Linux distribution for Amlogic devices. TinyPPI needs version 22 or later.
dvcC / dvvC	The Dolby Vision configuration record in the container: version, profile, level, and which layers are present.
DM compression	Dolby Vision metadata compression: most frames omit unchanged blocks (L2, L8 …); TinyPPI holds the last one and marks it Cached.
DT-DL / ST-DL / ST-SL	Dolby Vision layer structures: dual track dual layer, single track dual layer, single track single layer.
Effective HDR type	The HDR type the overlay layout follows; differs from the source type during a VS10 conversion when the Converted output settings say so.
EL	Enhancement layer of a dual-layer Dolby Vision stream (profile 7).
EOTF	Electro-Optical Transfer Function — the transfer curve signalled to the display (SDR gamma, PQ for HDR10/DV, HLG). Shown as Mode.
FALL / MaxFALL	Maximum Frame-Average Light Level — the brightest frame average of the title, in cd/m².
FEL	Full enhancement layer — a profile 7 EL carrying real picture data; reconstructs a 12-bit picture.
HDR10	HDR with static metadata (MDCV, CLL) and the PQ transfer.
HDR10+	HDR with dynamic metadata (SMPTE ST 2094-40). Not a VS10 input.
HLG	Hybrid Log-Gamma — broadcast HDR without metadata. Not a VS10 input.
Home window property	A named value on Kodi's Home window (id 10000). TinyPPI publishes state and colors there for its skin files.
IMAX Enhanced	A certification for releases with IMAX's expanded aspect ratio and DTS:X IMAX audio.
IPT / tunnelled IPT	Dolby Vision output formats: IPT for Player-LED, IPT tunnelled in an 8-bit RGB link for TV-LED ("DV Tunnel").
L1	RPU block with the frame's min / max / average luminance (PQ). Changes every scene.
L2 / L8	Trim passes: how the grade is adjusted for a target display (slope, offset, power, chroma, saturation …). L8 is the CMv4.0 version.
L3	PQ offsets to L1 (CMv4.0).
L4	Temporal stability metadata.
L5	Active area — the black bars (left, right, top, bottom offsets).
L6	Mastering display and MaxCLL/MaxFALL as carried in the RPU.
L9 / L10	Source primaries / target display definitions (CMv4.0).
L11	Content type, white point and reference mode.
L254 / L255	CMv4.0 marker block / debug run-mode block.
MDCV / MDL	Mastering Display Colour Volume — primaries and min/max luminance of the mastering display. TinyPPI shows the luminance as MDL.
MEL	Minimal enhancement layer — a profile 7 EL with (almost) no picture data.
NLQ	Non-linear quantization data the composer uses to merge the EL on dual-layer profiles.
nits / cd/m²	Units of luminance; 1 nit = 1 cd/m².
Passthrough	Audio sent to the receiver as an untouched bitstream.
Player-LED / TV-LED	Where Dolby Vision tone mapping happens: in the player (Player-LED, low-latency) or in the TV (TV-LED, the default).
PPI	Player Process Info — Kodi's name for its playback information view.
PQ	Perceptual Quantizer (SMPTE ST 2084) — the HDR10/Dolby Vision transfer curve. Raw PQ codes are 12-bit (0–4095).
Profile	Dolby Vision profile and compatibility ID, e.g. 5 (IPT single layer), 7.6 (dual layer, HDR10 BL), 8.1 (single layer, HDR10 BL), 8.4 (HLG BL).
RPU	Reference Processing Unit — the per-frame Dolby Vision metadata.
SEI	Supplemental Enhancement Information — metadata messages inside the video stream (MDCV, CLL, HDR10+).
Side data	The raw metadata payloads of the frame being decoded, published by CoreELEC 22 as Player.Process(video.sidedata).
Splash	TinyPPI's internal name for the codec logos.
SSE	Server-Sent Events — the one-way HTTP stream the dashboard uses for live updates.
VS10	Dolby's video engine in Dolby Vision-capable Amlogic chips; converts between SDR, HDR10 and Dolby Vision output.