[EXPERIMENTAL] CoreELEC 22 · samurihl DV build (20260724134638)

⚠️ EXPERIMENTAL · UNSUPPORTED · USE AT YOUR OWN RISK

This is an unofficial, experimental CoreELEC 22 build. It is NOT an official
CoreELEC release and it is NOT a supported CE22 port. I am not a CoreELEC 22
port maintainer, and I will not be providing support, bug fixes, updates, or
ongoing maintenance for this build.

The only purpose of this build is to give Amlogic AM9 Pro-class users a more
complete Dolby Vision experience than stock CoreELEC 22, by carrying a set of
custom Kodi features I built for my own device. That is the entire scope.

READ THIS BEFORE YOU FLASH ANYTHING

• USE ENTIRELY AT YOUR OWN RISK. There is no warranty of any kind, express
  or implied. It may fail to boot, misbehave, break Dolby Vision, or do nothing
  useful on your hardware.
• BACK UP YOUR CURRENT INSTALLATION FIRST. Take a full CoreELEC backup
  (Settings → CoreELEC → Backup) and/or image your existing boot media before
  you install anything from here. Assume you may have to restore it.
• Prefer a SEPARATE SD card or USB stick you can boot from, instead of
  overwriting a working internal (eMMC) install.
• Do NOT report problems with this build to the CoreELEC team or forums.
  This is not their build; it is not their responsibility. Do not ask them to
  support it.
• I am also not offering support. If it breaks, you keep both pieces.

By downloading or using any file in this release you accept all of the above.

Install

• Clean install (recommended): flash the *.img.gz to an SD card or USB with
  balenaEtcher (or the Amlogic USB Burning Tool for eMMC), then boot from it.
• In-place update: copy the *.tar to the /storage/.update folder on an
  existing CoreELEC install and reboot. (Back up first — see above.)
• Verify your download against the SHA256 sums below before flashing.

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What's changed in this update

This is an incremental update to
v22.0-samurihl-20260722204012
(see that release and its predecessors for the standing feature set: HDR10+ → Dolby
Vision conversion, DV → HDR10 that stays in HDR10, FEL profile‑7 reconstruction on
non‑DV displays, VS10 output on non‑DV displays, VSVDB override, tone‑mapping target
controls, disc‑menu playback). The headline this time is Blu‑ray disc menus: on
Dolby Vision discs the menus used to come up washed‑out, black, or with
jagged text, and subtitles and menu graphics could stick on screen. Those are
fixed — plus a steadier HDR10+ conversion and a Sony Dolby‑Vision fix.

⚠️ Still experimental and completely unsupported — see the disclaimer above.
Back up your current install before flashing.

Dolby Vision still requires dovi.ko (the CE22 5.15 build) installed on your
device — it is not bundled; install it yourself as on stock CoreELEC 22.

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🎬 Dolby Vision disc menus (BD‑J) now render correctly

On Dolby Vision Blu‑rays with Java (BD‑J) menus — Superman and many Warner titles —
the animated disc menu had three separate problems. All three are fixed:

• Washed‑out / grey menu graphics. The menu artwork is authored in BT.2020 PQ, but
  it was being treated as ordinary sRGB and encoded a second time, so every colour came
  out pale and grey. It's now pre‑corrected once at ingestion, so the menu shows its
  intended colours.
• Black screen when the menu opens. Entering the Dolby Vision menu forced an
  unnecessary display re‑clock on an already‑live mode, which re‑trained the HDMI link;
  on stricter TVs that left the screen black. The display is now only re‑set when the
  mode or refresh rate genuinely changes, so the menu appears immediately.
• Jagged / aliased menu text. Menu graphics are now composited through an sRGB
  intermediate and colour‑transformed once, post‑blend, so anti‑aliased edges and
  translucency blend correctly instead of fringing.

💬 Subtitles no longer stick on screen

PGS (Blu‑ray) subtitles could freeze on screen and stay there until the next caption
appeared — most visible on 4K Dolby Vision and SDR discs. Two causes: some discs deliver
a caption with no timestamp (it was being pinned to time zero), and the renderer only
repainted on a coarse "there is / isn't a subtitle" flag that the persistent disc menu
held permanently true. Captions are now anchored to the playback clock and the renderer
tracks the actual caption, so subtitles appear and clear on time.

🧹 Disc menus clear cleanly on start and stop

Two long‑standing menu‑plane glitches are gone:

• Menu lingering into playback. Starting a movie from the disc menu left part of the
  menu painted over the opening seconds until the video overdrew it. The menu overlay is
  now cleared on the genuine menu→feature transition.
• Menu (or subtitle) stuck on stop. Stopping playback while a menu was up — or while
  a subtitle was on screen — left it frozen on a black screen. On this box the on‑screen
  plane keeps scanning out its last frame until something repaints it, and at stop nothing
  did. The plane is now explicitly cleared at stop when a menu or subtitle is present, so
  it goes cleanly to black. (Overlay‑free stops are untouched — no added delay, no flash.)

🌈 HDR10+ → Dolby Vision conversion is steadier

The HDR10+ → DV conversion now holds the last valid dynamic metadata across brief gaps
in the source's HDR10+ information, instead of dropping to a default for those frames —
so brightness no longer twitches when a title's metadata stream has a hiccup. Scene peak
brightness is also clamped to the source's own maximum, keeping highlights faithful.

Credit: the HDR10+ → Dolby Vision conversion work is based on pannal's approach —
thanks to pannal for the groundwork this builds on.

🩷 Sony TVs: Dolby Vision demo no longer pink

On Dolby Vision displays, releasing the disc session (e.g. an HDR10 demo inside a DV disc)
could push the wire into the Dolby Vision tunnelling format when the output wasn't actually
Dolby Vision — which showed as a pink tint on Sony TVs (LG was unaffected). The
wire‑format force is now gated on genuinely‑DV output. This one wants Sony eyes — see
below.

✨ Also in this build

• Opening‑video judder at the menu→movie transition is smoothed (the display mode
  gate no longer re‑clocks on a fractional‑rate‑only difference).

How to help

The disc‑menu work wants real‑world eyes on Dolby Vision Blu‑rays with animated
(BD‑J) menus — confirm the menu comes up promptly (no black screen), shows its proper
colours (not washed‑out grey), has clean text, and that starting/stopping from the menu
leaves no leftover menu graphics on screen. Subtitle owners: confirm PGS subtitles on
4K DV and SDR discs appear and clear on time rather than sticking. Sony Dolby‑Vision TV
owners specifically: play an HDR10 demo/segment inside a DV disc and confirm there's no
pink tint (this fix has only been checked on LG so far). The standing DV → HDR10,
HDR10+ → DV, target‑luminance and TrueHD‑sync checks from earlier releases still apply.
When something misbehaves, grab a debug log (kodi-send --action=ToggleDebug), note
the disc/title, and report it. "Worked perfectly" reports help too.

Known rough edges (still open)

• VC‑1 discs still don't play (endless busy spinner) — known, open.
• 3D Blu‑rays (MVC) don't decode — known, open.
• A ~1/3‑second stream‑start trim remains at title start (matches stock player).
• Some BD‑J menu color‑correction twins (a few HDMV menu / subtitle graphics paths) may
  not yet be covered — report any menu that still looks washed‑out.

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Install

• Clean install: flash the Generic *.img.gz (SD/USB via balenaEtcher, or the
  Amlogic USB Burning Tool for eMMC).
• Update in place: drop the *.tar in /storage/.update and reboot.
• Verify your download against the SHA256 sums below before flashing.
• On other Amlogic-no boards (Odroid / Khadas / Radxa): use the *.tar update, or
  your board's own image.

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Source

• CoreELEC (distro): SamuriHL/CoreELEC tag v22.0-samurihl-20260724134638
• Kodi: SamuriHL/coreelec-xbmc tag v22.0-samurihl-20260724134638

Checksums (SHA256)

811011d777d79e011d88d08b6f38217f378b2da83e9d9b309da6d23934f48838  CoreELEC-Amlogic-no.aarch64-22.0-Piers-samurihl-EXPERIMENTAL_20260724134638.tar
245b987ea9cfa329405ab829130daf885fac98e72d2df565ae0434f341fccb02  CoreELEC-Amlogic-no.aarch64-22.0-Piers-samurihl-EXPERIMENTAL_20260724134638-Generic.img.gz