Release T2

[pannal]

p3i T2

This is the continuation of the initial T1 release with a lot of changes. In terms of GUI improvements it's not as game-changing as T1 was, but still has a lot of benefits, this time less around idle CPU usage, more around live GUI performance during usage.

UI rendering improvements

T1 was heavily focused on idle CPU reduction, T2 focuses on GUI transitions and large list performance. Here's a short summary of what's changed:

More detailed rundown

  ┌─────┬──────────────────────────────────┬───────────────┬──────────────┬───────────────┬────────────────────────────┐
  │  #  │           Optimization           │   Frequency   │  Complexity  │  Frame Time   │           Notes            │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │ 1   │ Cache render items vector        │ Every frame,  │ Heap alloc → │ ~2-5%         │ Biggest win; 10-50 item    │
  │     │                                  │ list views    │  reuse       │               │ vectors per frame on ARM   │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │     │ std::optional caches (scroll     │               │ Skip         │               │ Most impactful in          │
  │ 2   │ bar, panel, button alpha,        │ Every frame   │ redundant    │ ~1-3%         │ GUIControlGroupList (page  │
  │     │ control group list)              │               │ setters      │               │ control skip)              │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │ 3   │ CGUIImage batch dirty marking    │ Every frame   │ 6+ calls → 1 │ ~1-2%         │ Only during active         │
  │     │                                  │ during fades  │              │               │ cross-fade transitions     │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │     │ CGUIImage skip redundant diffuse │ Every frame,  │ Compare      │               │ Saves per-image work when  │
  │ 4   │  color                           │ per image     │ before       │ ~0.5-1%       │ color unchanged            │
  │     │                                  │               │ update       │               │                            │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │     │ GUIFadeLabelControl dirty        │ Every frame,  │              │               │ Fewer fade labels than     │
  │ 5   │ consolidation                    │ scrolling     │ 2 calls → 1  │ ~0.5-1%       │ images typically           │
  │     │                                  │ labels        │              │               │                            │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │     │ Message deduplication            │ Per GUI       │ Prevent      │               │ Reduces message processing │
  │ 6   │ (std::any_of)                    │ message       │ duplicate    │ ~0.5%         │  overhead                  │
  │     │                                  │               │ queue        │               │                            │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │     │                                  │ Every frame,  │ Skip         │               │                            │
  │ 7   │ CGUITexture ready state cache    │ per texture   │ redundant    │ ~0.5%         │ Minor per-texture saving   │
  │     │                                  │               │ eval         │               │                            │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │     │ GUILargeTextureManager O(1)      │ Per frame,    │              │               │                            │
  │ 8   │ lookups                          │ thumbnail     │ O(n) → O(1)  │ ~1-5ms/frame  │ 100+ loaded thumbnails     │
  │     │                                  │ views         │              │               │                            │
  ├─────┼──────────────────────────────────┼───────────────┼──────────────┼───────────────┼────────────────────────────┤
  │ 9   │ Binary search letter navigation  │ On user input │ O(n) → O(log │ imperceptible │ Correctness optimization   │
  │     │                                  │  only         │  n)          │               │                            │
  └─────┴──────────────────────────────────┴───────────────┴──────────────┴───────────────┴────────────────────────────┘

  Summary by scenario:
  ┌───────────────────────────────────────────────┬───────────────────────────────┐
  │                   Scenario                    │     Estimated Improvement     │
  ├───────────────────────────────────────────────┼───────────────────────────────┤
  │ Typical list/panel views                      │ ~3-8%                         │
  ├───────────────────────────────────────────────┼───────────────────────────────┤
  │ During cross-fade transitions                 │ ~5-10%                        │
  ├───────────────────────────────────────────────┼───────────────────────────────┤
  │ Large library (1000+ items) scrolling/refresh │ ~10-20%                       │
  ├───────────────────────────────────────────────┼───────────────────────────────┤
  │ Letter navigation in large lists              │ instant vs. potentially laggy │
  └───────────────────────────────────────────────┴───────────────────────────────┘

By now a big chunk of my GUI improvements have made it into Kodi itself and thus will be available to any Kodi user in the future.

Other notable changes

• Add a very subtle boot animation to show we haven't crashed (the ring around the power button pulses)
• Add DV Video Processor support and align with avdvplus
  I've carefully rebased our settings and video path on avdvplus R6's state, adopting the video processing logic and all the other features (and caveats of this in R6). Our DV and video paths are now not based on CPM anymore, but were carefully tested including full compatibility with PM4K and LAV filters without issues.
  Dissected from avdvplus in xbmc and kernel
• AMLCodec: Improve VC-1 hardware decoding (not a definitive fix)
  Based on fixes from CoreELEC and avdvplus R5.
• LAV/PackerMAT: Preserve numberOfSamplesOffset across seamless branch points
  This results in better A/V sync at seamless branching branch points
  Based on SamuriHL aa0b362 and avdvplus R6.
• Add avdvplus R6 HDR10+/DV improvements
• [ActiveAE] Allow configure "Low latency mode" during playback
  Via thexai, Kodi 22
• VideoPlayer: Reset PTS offset on flush
  Guarantees continuous perfect subtitle sync after multiple seek attempts. Slightly changes seeking (with certain, especially PCM audio codecs, this leads to a small blip after seeking which resolves itself after a second); optional setting, on by default
  Via neo1973, Kodi 22
• AEStreamInfo: fix AC3 duration when sample rate is different from 48 KHz
  Via thexai, Kodi 22
• VideoPlayer: increase correction threshold to 1000ms (for DTS "classic" only)
  This fixes issue #26647 increasing the threshold for timestamp sync correction from 500ms to 1000ms avoiding correction issues for videos having the first keyframe between 500ms and 1000ms.
  Partially via seppiola, Kodi 22
• Addition of Player.GetChapters in JSON RPC
  Via albaintor, Kodi 22
• JSON RPC: added notifications (Player.OnPropertyChanged)
  Via albaintor, Kodi 22
• [GUI] GUIWindowManager: Use shared_ptr for window ownership
  Fixes a crash during ReloadSkin (update) when a modal dialog was active
  Via enen92, Kodi 22, 1, 2, 3
• Fix playback of tcp streams
  Via enen92, Kodi 22
• VideoPlayer: Seek demuxer on embedded subtitle stream change
  Fixes a long standing Kodi issue where embedded subtitles could take up to 20-30 seconds to show up. This adds a very short seek-back hitch when changing (to) embedded subtitles, but shows them instantly.
  Via myself
• Settings/System/CoreELEC: LAV: Adjust setting label and values
• Settings/System/CoreELEC: Move LAV into separate group

CoreELEC Settings Addon

• MainWindow: Scroll address label to accomodate larger fonts
  IP addresses could've been hidden when non-default fonts were selected
• Fix slow shutdown by making LOOP_THREAD a daemon thread
• Fix Bluetooth device not being trusted after pairing (long standing issue)
• Backport LibreELEC-Settings' journald log persistence (logs can now be persisted during reboots to make identifying core issues easier)
• Improve bluetooth discovery and pairing
• Clean up device on pairing failure

General info on this release

All in all T2 should improve over T1 in general, adding the nice new features from R6, a lot of A/V sync improvements (LAV totally unnecessary right now, unless seamless branching titles are used), while retaining full compatibility. Should you run into any weird buffering issues, reflash and/or increase your Kodi cache slightly.

Should you have issues with bluetooth remotes, please unpair them, disable bluetooth, reboot, enable bluetooth, then pair again. Make sure you have another navigation device ready (TV remote via CEC, Kodi Kore).

Any active forced DV to X conversion video processor mode aside from HDR2 (Auto off) can result in a pink UI during playback. This is currently unsolved in both R6 and T2.

As stated above briefly, we've had multiple core changes to ensure perfect A/V sync in almost all scenarios (VC-1 is the exception), which leads to slightly different behaviour during seeking. This is expected and shows up predominantly when using non hw passthrough audio codecs, such as AAC (PCM). A short audio/video catch-up phase after seeking was deemed less intrusive than potential A/V desync issues.

Installation

1. Dirty

Drop the update tar into your CoreELEC update folder and reboot - this can be used as a dirty upgrade from CPM A14 or any of the U3k builds.

Should hitting reboot result in a black screen (long standing issue with any build), wait 10 seconds, then unplug and re-plug the device's power. The upgrade will commence afterwards.

Caution

Resetting Settings/System/CoreELEC to defaults after doing this is necessary. Not the CoreELEC Settings Addon!

2. Dirty (safe)

Drop the update tar into your CoreELEC update folder, shut down the device, pull the power plug for 30 seconds, replug.

Caution

Resetting Settings/System/CoreELEC to defaults after doing this is necessary. Not the CoreELEC Settings Addon!

3. Flash

Use the provided Flash img.gz to prepare your SD card as you would with any other CoreELEC build.

advancedsettings.xml

If you'd like, you can add the following to your advancedsettings.xml, which further improves UI rendering, but is not strictly necessary:

<advancedsettings version="1.0">
  <gui>
      <fronttobackrendering>true</fronttobackrendering>
      <geometryclear>false</geometryclear>
  </gui>
</advancedsettings>

Make sure the XML format is correct, otherwise the file will not be read at all. If you already have such a file, only add the parts.

Thanks

A massive shoutout to everyone involved in this build!

Full Changelog (Kodi core): https://github.com/pannal/xbmc/commits/T2
Full Changelog (CoreELEC-Settings): https://github.com/pannal/service.coreelec.settings/commits/T2
Full Changelog (Kernel): https://github.com/pannal/linux-amlogic/commits/T2

---

This discussion was created from the release Release T2.

[nissel]

Thank you, this looks really great.

What does the Player Led (HDR2) option do compared to the HDR one?

[pannal]

It's a better mode introduced with the avdvplus kernel and xbmc merges.

The difference from the original PLAYER_LED_HDR is that HDR2 is a newer video processor variant (introduced alongside the avdvplus R6 HDR10+/DV improvements).

The practical benefit: HDR2 gives the Amlogic DV video processor more freedom in how it handles LLDV streams. With dolby_vision_hdr_for_lldv = N, the processor can output using its own tone-mapping rather than being forced into HDR tone-mapping. This can result in better color accuracy and dynamic range on displays that support HDR PQ but not full Dolby Vision — the VS10 engine handles the DV-to-HDR conversion internally with potentially newer/improved algorithms (R6 generation), rather than being constrained to the older HDR-for-LLDV path.

[pannal]

As stated in the release notes: The new video processing modes (HDR2 + Auto VP or any of the 444/422 explicit DV conversion modes) can introduce wrong colors on the OSD during playback. This is the only caveat right now.

HDR2 without Auto VP should not experience wrong GUI colors.

[stigger]

Trying to build it locally:

UNPACK      kodi
error: File xbmc-local doesn't exist for package kodi
Have you called scripts/extract before scripts/get?
FAILURE: scripts/unpack kodi during unpack (default)
*********** FAILED COMMAND ***********
${SCRIPTS}/extract "${PKG_NAME}" "${PKG_UNPACK_DIR}"
**************************************
*********** FAILED COMMAND ***********
${SCRIPTS}/unpack "${p}" "${PARENT_PKG}"
**************************************
*********** FAILED COMMAND ***********
${SCRIPTS}/unpack "${PKG_NAME}" "${PARENT_PKG}"
**************************************
FAILURE: scripts/build JsonSchemaBuilder:host has failed!

[pannal]

Yeah if you're using the local branch, you need to check out my other repositories as well. You can adjust the location of these in the respective CE files.

[stigger]

I'm using the T2 tag :)

[pannal]

You still need to use the coreelec-21_local branch for local building and adjust the paths according to your setup

[abc1nr3]

Should I still put Dovi.ko in root menu?

[CE-Repo]

I am very impressed with T2, much better than avdvplus’s version.
I look forward to more cool releases.

[GooberedUp]

I'm running T2 and it seems to be working fine. But does it have limitations on the Homatics box that may not be present with some of the other builds out there? I'm using the Estuary skin by Frodo.

[pannal]

Guys, I realized why there's some confusion about the DV/VP modes in T2. They map fully against the ones in R6, but are named differently. Also the Seek/Sync option for Audio Fixes/LAV are missing. There'll be a T2a that will clear this up.

[mrmorrison85]

Thank you so much for this new job! Is it correct to say that with DV-LL (not video processor) output there is no difference with DV-LL of the R6 build (not video processor)? My tv support Dolby Vision but ongly low latecy
Or are there any differences?

[pannal]

Preparing T2a right now, as we're not yet fully aligned with avdvplus R6 DV/VP settings.

[DrGonzo3000]

Can you explain the new option “Set DV Metadata Level 5 to original source instead of 0”?

This is disabled by default. From what I gathered, L5 Metadata contains the CanvasAspectRatio and ImageAspectRatio. Leaving it at source tells the TV what part of the screen contains the image and what part is the letterbox (so that tonemapping isn't applied to the black bars?).

On my old Hisense TV I've always had flickering letterbox bars though (even when set to source):

Now I have a LG G5, and I can't see any difference between the settings (Level 5 on, 0, or on + subtitle/osd fix). I can always see the subtitles/osd, and my bars aren't flickering.

Can you clue me in what this setting is for exactly, why it's off as default, and why you removed the "discard" option? (what's the difference between "0" and "discard" anyway?

Sorry for all those questions, but it's one of the last settings I just don't understand...

[pannal]

Preparing T2a right now, as we're not yet fully aligned with avdvplus R6 DV/VP settings.

[pannal]

T2a out, please continue here!