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LG OLED 2019 PQ Curve Upload Free Template for DeviceControl Interface

Its been released the LG 2019 PQ Curve Upload Template REV.1 (28 August 2019) Free Template for all users of DeviceControl Interface which add support for Custom PQ Curve Upload (7 HDR10 tone mapping parameters) for LG 2019 C9/E9/W9/Z9/R9 OLED TV's.

This template is free for all people, whatever calibration software they will use, it will be useful even for CalMAN users, where they can install it to a different PC from the one they use for calibration, or to any windows based tablet, for quick upload or custom tone mapping settings.

There full instructions about how to install DeviceControl, how to create an account to the DeviceControl Cloud, and about how to submit for getting that free table here.

Some info about below:

LG 2019 OLED TV's feature a Dynamic Tone Mapping algorithm (Picture -> Picture Mode - Setting -> Expert Controls).

When Dynamic Tone Mapping is enabled 'On', the HDR10 tone-mapping curve will be dynamically generated after analysis of signal peak and histogram information on a frame by frame basis.

When Dynamic Tone Mapping is disabled 'Off', the LG TV will use the default 'factory' HDR10 tone curve parameters (Peak Luminance, 3x Tone Curve Metadata Point and 3x Roll-Off Point) and will determinate the PQ Luminance of content based to the HDR10 compliant stream static metadata info (SMPTE ST.2086, MaxFALL and MaxCLL) as follows:

1) Use ST.2086 Mastering Metadata - Mastering Display Color Volume -> Maximum Display Luminance value.

2) If 'MaxCLL' (Content Metadata -> Maximum Content Light Level) is present and lower than the ST.2086 Maximum Display Luminance value, use MaxCLL.

3) If ST.2086 Maximum Display Luminance and MaxCLL are both signaled as zero (as defined for un-available), assume a peak luminance of 4000 nits.

LG 2019 OLED TV's PQ Curve Upload Template is providing a DDC interface to configure and upload these 7 tone mapping engine calculation parameters data to the TV, to match the actual measured (calibrated) peak luminance of your display and adjust the roll-off point for 3 different user-specified mastering display peak value (Maximum Display Luminance) HDR10 ST.2086 static metadata of your HDR10 content.

That template can be used from any user, even if it has calibrated his display or not. It doesn't matter what software will be used to calibrate the display.

When the user has calibrated his display using HDR10 patterns, it will be required to set the calibrated peak output 'nits' values to the Peak Luminance parameter.

For users which will only want to test different tone-mapping parameters and don't have any calibration instrument/software, then the default '700' value to the Peak Luminance parameter should be used.

The Peak Luminance parameter is the most important setting for the proper tone-mapping calculations.

HDR10 Tone Mapping default 'factory' parameters values

Peak Luminance: 700 nits

Metadata Point 1: 1000 nits

Roll-Off Point 1: 70%

Metadata Point 2: 4000 nits

Roll-Off Point 1: 60%

Metadata Point 1: 10000 nits

Roll-Off Point 1: 50%

Use these values if you want to restore the 'factory' default settings.

Explanation of HDR10 tone mapping engine parameters

Peak Luminance: Used to set the target output luminance range for tone mapping calculations. Measure your calibrated peak white using a 100% White pattern (940 digital level) with 10% window size (L32 loading) pattern with black background.

To verify how the roll-off point value affects the PQ curve tracking, you have to generate HDR10 patterns with the same 'Maximum Display Luminance' value as the Metadata Point number (1,2 or 3) vales you want to test.

Tone Curve Metadata Point (3x): Used to define which content metadata peak luminance 'Maximum Display Luminance' value you are defining the tone curve for.

Roll-Off Point (3x): Used to se the point at which the tone curve deviates from PQ, expressed as a percentage of the Peak Luminance value.

With the 3 Metadata and Roll-Off Points, it is possible to accurately define tone curves for content with 3 specified metadata points; as example for 1000/4000/10000 nuts peak content.

Content with metadata peak luminance 'Maximum Display Luminance' value between these points will result in a tone curve that is interpolated between the three defined points.

If a PQ 'Hard Clip' is desired regardless of content metadata the TV will receive, for content creation purposes, or to use the display as a PQ reference, this can be easily achieved by setting all three Roll-Off Parameters to 100%.

It will be interesting about what will be the calibration results if the user will calibrate with PQ curve parameters applied to provide a 'Hard Clip' and then after the calibration to restore them back to normal values.

Using that method, you will calibrate using the normal TV RGB Balance controls but without any tone-mapping as active.

If content metadata signals a peak luminance lower then the Peak Luminance Tone Curve Parameter, a Peak Hard Clip tone curve will be used, tracking PQ up to the Peak Luminance Tone Curve Parameter and clipping content at higher luminance.

When you are calibrating HDR10 using the available to normal TV menu RGB balance controls (without bypassing the HDR processing math’s), all these available RGB Balance controls adjustments are taking place in Gamma space. If the panel peak luminance is higher or lower that the assumed peak luminance of the HDR processing math’s, you may find yourself pushing the grayscale adjustments in odd directions to compensate, resulting in the potential for banding.

How to upload the PQ Curve parameters data to the LG 2019 OLED TV

1) Click the 'Send Icon' on 'Request Pin' to request LG OLED TV to show the pin number.

2) LG OLED TV should pop-up a window with a pin number. Enter it on 'Set Pin' input box and click the 'Send Icon'.

3) Click on 'Enable Calibration' checkbox.

4) Set the 7 parameters for custom HDR10 Tone mapping to the values you desire.

5) Click to 'Send Icon' for the 7 parameter values to be transferred to the TV Tone Mapping engine.

6) Click on 'Enable Calibration' checkbox to disable the connection with the TV for the procedure to complete.

When you have 'Enable Calibration' checkbox ticked, the changes of the parameters you will upload they will not affect the picture, since the HDR10 Tone Mapping at this step has been disabled and content is displayed as gamma based with inaccurate colors. This is normal behavior. You have to untick the 'Enable Calibration' to be able to see the changes you have apply.

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Last edited by ConnecTEDDD; 09-02-2019 at 01:57 PM.
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