Ultimate-HyperHDR-Ambilight-fine-tuning-experience-for-LG-webOS-with-new-LUT-calibration-

Attention!

This guide is not part of the official HyperHDR for WebOS from the homebrew channel and should not be followed unless you are willing to try something different from what is provided in the homebrew channel and get the maximum colour rendering from different LUTs. Everything here is experimental and constantly being tweaked as @awawa-dev makes changes. There is no guarantee that the colour reproduction will be equally good on all devices. You may need to make adjustments yourself or even calibrate your external playback source.

Note

Since some inexperienced users recently found this guide too complicated and also encountered errors when running it, I decided to simplify it so that everyone can run it.

With the changes in the PicCap UI, the additional code from @neogeo for the HyperHDR installer and the countless tips from @awawa-dev, I was finally able to put together a new HyperHDR version that simplifies everything.

This guide is based on @awawa-dev NV12 implementation and new LUT calibration method in HyperHDR, @sundermann NV12 customisation in hyperion-webos, @neogeo Add Settings Panel with LUT installation selector option in Settings menu of hyperhdr-webos-loader and Add NV12 to PicCap-UI by @TBSniller & @satgit62.

PiCap v0.5.0 and HyperHDR 21.0.0.0beta2 (org.webosbrew.hyperhdr.loader_0.2.1_all.ipk) are required to use this guide.

The implementation and utilization of the NV12 image format in HyperHDR now offers numerous enhancements and the capability to achieve precise color matching even in our exotic LG webOS by utilizing the YUV format in lieu of RGB.

Advantages:

The NV12-YUV conversion has been completely moved to HyperHDR, which uses a LUT table for this purpose (no calculations when converting from YUV to RGB). Using the selected LUT, the YUV to RGB conversion and tone mapping can also be performed in one step without loss. This means that we reduce the client load, as not only is the processor load reduced, but no additional resources, e.g., memory, need to be allocated. You also do not need to use external YUV libraries. Reduced load on the connection bandwidth. The NV12 frame is around 50% smaller than the RGB frame. This means that the automatic LUT calibration with YUV coefficient detection can be fully utilized.

Important!

If the NV12 transport mode is used, HyperHDR requires a complete standard LUT table (150 MB). The small flat_lut_lin_tables.3d table used (50 MB) does not contain the necessary YUV conversion tables and only works for RGB tone mapping.

Another problem was the use of a LUT table for different video types. With SDR video material, for example, the colors of the LEDs matched, but with HDR the colors were distorted and very weak with Dolby Vision. Thanks to a new calibration method implemented in HyperHDR, it is now possible to generate LUT tables with different color information depending on the video material being played.

The following lines of code were added under other changes, by @s1mptom and @sundermann to the definition of the LUT table in the hyperion-webos backend (PicCap).

Source code:

   * #define LUT_TABLE_FILENAME_HDR “lut_lin_tables_hdr.3d”
   * #define LUT_TABLE_FILENAME_DV “lut_lin_tables_dv.3d”
   * #define LUT_TABLE_FILENAME_SDR “lut_lin_tables.3d”

In our case, this means that the new LUTs (lut_lin_tables.3d, lut_lin_tables_dv.3d and lut_lin_tables_hdr.3d) replace the standard LUTs.

Thanks to the implementation of a new ZSTD compression process by @awawa-de, compressed LUTs are now permitted and available without any loss of quality. They are automatically detected and applied in real time.

* lut_lin_tables_hdr.3d.zst
* lut_lin_tables_dv.3d.zst
* lut_lin_tables.3d.zst

I have recompiled the “hyperhdr-webos-loader” with the following new feature:

Add Settings Panel with Lut install selector by @neogeo
Fix HyperHDR daemon when starting calibration process by @satgit62
Fix HyperHDR daemon at screensaver start (The HyperHDR daemon is no longer stopped when the internal screensaver or the custom Aerial Screensaver for webOS is switched on. (Ambilight works) by @satgit62

The following features have been added to HyperHDR 21.0.0.0beta2 by @awawa-dev:

Support for Home Assistant lights
Experimental direct support for zigbee2mqtt
Support for ZSTD compression for all LUT files
Added support for NV12 image format for flat buffers by @awawa-dev
ai_calibration by @awawa-dev
Denoising algorithm that significantly improves calibration results with YUV420 format, especially YUV420 LIMITED by @awawa-dev
Added Quarter of frame for NV12 for Flatbuffers Server reduces CPU and memory load by @awawa-dev
Grabber benchmark support for flat buffers by @awawa-dev
Added support for SDR (BT2020 in SRGB) calibration by @awawa-dev
More precise saving/loading of color images by @awawa-dev
Corrected calibration for 1280×720 recording settings by @awawa-dev

UPDATE vom 29.01.2025:

Version 0.5.0 of PicCap with the new backends and NV12 has been officially released in the Homebrew Channel. 😃

To avoid errors, please do not use any other version!

https://github.com/TBSniller/piccap/releases/download/0.5.0/org.webosbrew.piccap_0.5.0_all.ipk

After successful installation and Services Elevation, you need to reboot, open PicCap, configure to your liking, enable NV12, enable autostart, save and reboot.

Attention!

When using the NV12 option with multiple LUTs, please do not activate the "Disable HyperHDR SDR/HDR switch" option in the advanced settings of PicCap under any circumstances.

2. HyperHDR installation instructions:

How to install .ipk files without Homebrew Channel can be found in my other guide. See: https://github.com/satgit62/How-to-Install-and-set-up-Ambilight-on-LG-webOS#manual-installation-of-apps-without-homebrew-channel.

Please use only this version for these instructions. https://github.com/satgit62/satgit62.github.io/releases/download/v0.2.0-alpha/org.webosbrew.hyperhdr.loader_0.2.1_all.ipk

To avoid errors, please uninstall HyperHDR webos-loader if you have installed a previous version. Your settings will be preserved.

a. Start HyperHDR app and stop the services/daemon.
b. Start webOS Dev Manager on the PC and uninstall HyperHDR.
c. Install the new webos HyperHDR loader (org.webosbrew.hyperhdr.loader_0.2.1_all.ipk).
d. Start the HyperHDR application and go to the settings in the top right corner. (gear wheel) See image.

e. The next step is to select the LUT version to install. Compressed and uncompressed LUT versions are available for NV12. By default, only one LUT is installed and NV12 must be disabled in PicCap.

After you have selected/approved the LUT, wait until Success! appears in the bottom left corner of Result.

f. Click on the left arrow in the top left-hand corner of the menu to go to the main menu.
g. Use the slider to activate the Automatic start option.
h. Start the daemon by clicking on Start. Wait until the start is displayed.
i. Reboot. Make sure that Quick Start+ in the menu of your LG is switched off.

The uncompressed LUTs are installed to /media/developer/apps/usr/palm/services/org.webosbrew.hyperhdr.loader.service/hyperhdr/ and the corresponding symlinks are set to /home/root/.hyperhdr/. The compressed LUTs will be installed in /home/root/.hyperhdr/.

Note

If NV12 mode has been successfully activated, this is displayed in the HyperHDR log:

[FLATBUFSERVER] (FlatBuffersServer.cpp:xxx) Received first NV12 frame and instead of “(LutLoader.cpp:x) Index 0 for HDR RGB”, “(LutLoader.cpp:x) Index 1 for HDR YUV”

When switching from an SDR video to an HDR or DV video, the LUT requested by the backend is searched for, loaded into HyperHDR and displayed in the log:

[FLATBUFSERVER] Setting user LUT filename to: 'lut_lin_tables_dv.3d'
[FLATBUFSERVER] (LutLoader.cpp:82) LUT file found: /home/root/.hyperhdr/lut_lin_tables_dv.3d

Remark:

SDR to HDR tone mapping must always be activated for NV12. Also for SDR content. This is how it should look for SDR, but also for HDR or DV content.

LUT

If you decide to calibrate LUTs yourself, make sure that you set the resolution in PicCap/hyperion-webos to Manuel and set 1280 × 720, save and restart. The new function in HyperHDR “Quarter of frame for NV12” under Network, Flatbuffers server must also be switched off for this process. (otherwise you will get the minimum requirement for calibration of 1280 × 720 in HyperHDR) After a successful calibration, you can reduce the resolution in PicCap and reactivate the option ‘Quarter of image for NV12’ in HyperHDR only if the CPU load is too high.

Note: Enabling 'Quarter of image for NV12' will reduce the CPU load, but the image resolution will be reduced accordingly. However, this is enough to control the LEDs correctly.

Attention!

Some devices absolutely need 360x180. In this case, do not activate ‘Quarter of image for NV12’.

The most common resolutions for PicCap are:

Note on calibration videos:

SDR refers to content without HDR/HLG or Dolby Vision. For this, you also have to use a calibration video such as calibration_HDR_yuv420_limited_range.mp4, calibration_SDR_yuv420_limited_range.mp4, for_testing_after_calibration_HDR_yuv420_limited_range.mp4

For DV calibration, use the test_DV_yuv420_low_quality.mp4 file. See above in Main

So take the appropriate videos for the desired LUT calibration.

Using different players and test files (calibration videos) may slightly affect the calibration result and color reproduction, so it is better to test different combinations if something does not fit.

Important!

At the end of calibration, the LUT is automatically saved in /home/root/.hyperhdr/ under the name lut_lin_tables.3d.

If the calibration was not performed for SDR, the LUT must also be renamed with the correct name lut_lin_tables_hdr.3d or lut_lin_tables_dv.3d and moved to the correct directory.

See also the calibration guide from @awawa-dev: https://github.com/awawa-dev/HyperHDR/wiki/lut-calibration

If you would like to compress your self-calibrated LUTs, please read the following instructions:: https://github.com/satgit62/How-to-compress-the-LUT-table-and-use-it-in-HyperHDR