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post #1 of 19 Old 09-02-2019, 12:04 PM - Thread Starter
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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.

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post #2 of 19 Old 09-26-2019, 06:05 AM - Thread Starter
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How to use the LG 2019 PQ Curve Upload Template for DeviceControl Interface with LG 2019 OLED TV's.

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 'Maximum Display Luminance' value, it will use MaxCLL value.

3)
If ST.2086 Maximum Display Luminance and MaxCLL are both signaled as zero (as defined for un-available), it assumes and use 4000 nits values as 'Maximum Display Luminance'.



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

That template can be used from any LG 2019 OLED TV user, even if his display has been calibrated or not. It doesn't matter what calibration software will be used to calibrate the LG 2019 OLED TV in HDR10 mode.

When the user has calibrated the display using HDR10 patterns, it will be required to set his measured 100% White calibrated peak output 'nits' to the 'Peak Luminance' parameter value.

For users without any calibration instrument/software who want only to test different tone-mapping parameters, then the default '700' nits value to the 'Peak Luminance' parameter should be used.

For users with calibrated displays from professional calibrators, its not recommended to change any value unless they can get the info from their professional calibrator of what value for Peak Luminance parameter its been uploaded after calibration, as there no way to see what value the professional calibrator has entered internally to the LG 2019 OLED TV.

As a tip, the panel Peak Luminance number in nits can be found to the professional calibrator post-verification grayscale report. This is a detail the user has to discuss with the professional calibrator first, before adjusting the Peak Luminance parameter. When the user will know the Peak Luminance parameter value, then any custom adjustment upload of other parameters it will not alter/undo the current calibration, it will only change the tone-mapping behavior.

The Peak Luminance parameter is the most important setting for the proper tone-mapping engine 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 2: 60%

Metadata Point 3: 10000 nits

Roll-Off Point 3: 50%

Use these values above if you want to restore the 'factory' default tone-mapping parameter values.

Explanation of HDR10 tone mapping engine parameters

Peak Luminance: Used to set the target output luminance range for tone-mapping engine calculations. Measure your calibrated peak white using a 100% White pattern (940 digital level) with 10% window size (L32 loading) pattern with black background. The 'nits' number of that peak white measurement it will be the 'Peak Luminance' value of that panel.

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) value you want to test.

'Maximum Display Luminance' is the peak luminance of the mastering monitor used for color grading of each HDR10 title. Currently, industry is using 1000/1100/4000 or 10000 nits capable post-production monitors. The 'Maximum Display Luminance' info is part of each movie HDR10 Metadata InfoFrame.

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

You have the option to define the TV tone-mapping engine behavior (based to the entered roll-off point setting) for 3 different 'Maximum Display Luminance' (peak luminance of the mastering monitor used for color grading) scenarios.

For example, if you set to 'Tone Curve Metadata Point 1' the '1000' nits value, when you will playback a movie with HDR10 Metadata of 1000 nits @ 'Maximum Display Luminance', the TV will adjust the tone-mapping based to the entered 'Roll-Off Point 1' value for that content.

As there available 3x Tone Curve Metadata Point selections, it's up to the user preference which 3 different values he will pre-define.

To provide more help to the user's decision for these 3 'Tone Curve Metadata Point' values, from a very large list I personally keep with HDR10 metadata of many titles, below you will find a summary of current 'Maximum Display Luminance' values HDR10 titles are using:



Roll-Off Point (3x): Used to set 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 nits peak content.

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

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

It will be interesting about which 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 'Hard Clip' method, you can calibrate using the normal TV RGB Balance controls but without any PQ curve tone-mapping active.

If content metadata signals a peak luminance lower than 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 HDR10 Tone-Mapping 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.


Banding also called as false contouring or posterization, refers to unrealistic solid strips of color in areas that should display a smooth transition.

How HDR10 PQ-Curve Tone Mapping works?

An HDR image is encoded using a perceptual quantizer opto-electrical transfer function (hereinafter, PQ-OETF) defined by the society of motion picture and television engineers (SMPTE) ST.2084 and has a high dynamic range of 0 to 10000 nits.

LG 2019 OLED TV will need to perform an image processing procedure using a perceptual quantizer electro-optical transfer function (PQ-EOTF) defined in SMPTE ST.2084, in order to display an HDR image.

When the peak luminance output capability of the LG 2019 OLED TV is not matching the luminance level performance of the mastering monitor used for content mastering, then some tone-mapping processing have to be applied.

Tone-Mapping procedure remaps luminance from the source values to the lower values the display can reproduce.

The LG 2019 OLED TV Tone-Mapping image processing module utilize 2 mapping functions.

When the content will have 'Mastering Display Color Volume -> Maximum Display Luminance' value equal or lower from PQ Curve Tone-Mapping 'Peak Luminance' parameter or when the MaxCLL number is lower from content 'Mastering Display Color Volume -> Maximum Display Luminance' value, then the calibrated TV will track accurately the PQ-EOTF up to 'Peak Luminance' value and it will hard-clip above of that value. In that case the TV's Tone-Mapping image processor will use only the first tone-mapping function and it will bypass the second tone-mapping function (roll-off).

When the content will have 'Mastering Display Color Volume -> Maximum Display Luminance' value higher from PQ Curve Tone-Mapping 'Peak Luminance' parameter, then the image processor will see if the Metadata point 1, 2 or 3 has the exact same value as the content 'Mastering Display Color Volume -> Maximum Display Luminance'. If there present such entry, then the second mapping function will be enabled, using the entered percentage value of the 'Roll-Off Point' value for the roll-off calculation, based to the 'Peak Luminance' entered value.

In that case, the TV's Tone-Mapping image processor will use the first tone-mapping function to track accurately the PQ-EOTF up to the entered percentage value of 'Roll-Off Point' (knee point), based to the 'Peak Luminance' value and it will deviate from PQ-EOTF by using a smooth Roll-Off curve until the 'Peak Luminance' value.

The Roll-Off works as a form of compression, so when the content was been mastered for 4000 or 10000 nits, the compression will be even higher.

You can see to the picture below how Tone-Mapping works; with detailed explanation; when you have an LG 2019 OLED TV panel with 820 nits calibrated peak output, using the default Metadata Point & Roll-Off Point parameter values:



Hard Clip: When you have upload to all 'Roll-Off Point' parameters 100% values, then the tone mapping processor will track accurately the PQ-EOTF up to 820 nits and it will 'hard clip' the content above to the entered 'Peak Luminance' parameter value (820-10000 nit code values).

Tone Map 1: When you have a panel with calibrated peak output of 820 nits as entered to the 'Peak Luminance' value parameter, and have configured the Metadata Point 1: 1000 nits / Roll-Off Point: 70%, when the 'Mastering Display Color Volume -> Maximum Display Luminance' value of the content will have 1000 nits, initially the tone-mapping processor with remap the content dynamic range 0-1000 nits to match the panel dynamic range 0-820 nits and then perform a hard clip of 1000-10000 nit code values of the content.

The first tone-mapping function will track accurately the PQ-EOTF up to 70% of the Peak Luminance until 574 nits (820 nits peak * 0.7 roll-off = 574 nits) and the second tone-mapping function will tone map the code values of 574-1000 nits using a smooth rollover curve to match the panel 574-820 nits range.

Tone Map 2: When you have a panel with calibrated peak output of 820 nits as entered to the 'Peak Luminance' value parameter, and have configured the Metadata Point 2: 4000 nits / Roll-Off Point: 60%, when the 'Mastering Display Color Volume -> Maximum Display Luminance' value of the content will have 4000 nits, initially the tone-mapping processor with remap the content dynamic range 0-4000 nits to match the panel dynamic range 0-820 nits and then perform a hard clip of 4000-10000 nit code values of the content.

The first tone-mapping function will track accurately the PQ-EOTF up to 60% of the Peak Luminance until 492 nits (820 nits peak * 0.6 roll-off = 492 nits) and the second tone-mapping function will tone map the code values of 492-4000 nits using a smooth rollover curve to match the panel 492-820 nits range.

Tone Map 3: When you have a panel with calibrated peak output of 820 nits as entered to the 'Peak Luminance' value parameter, and have configured the Metadata Point 3: 10000 nits / Roll-Off Point: 50%, when the 'Mastering Display Color Volume -> Maximum Display Luminance' value of the content will have 10000 nits, initially the tone-mapping processor with remap the content dynamic range 0-10000 nits to match the panel dynamic range 0-820 nits.

The first tone-mapping function will track accurately the PQ-EOTF up to 50% of the Peak Luminance until 410 nits (820 nits peak * 0.5 roll-off = 410 nits) and the second tone-mapping function will tone map the code values of 410-10000 nits using a smooth rollover curve to match the panel 410-820 nits range.

Ideally, for the most accurate calibration and for keeping as high as possible the artistic intent of the content, it will be to disable any tone-mapping, so to let the display follow the PQ-EOTF up to the maximum nits the panel can output. This can be performed by uploading to all 'Roll-Off Point' parameters to 100% values. Doing this, the panel will track as best as possible the PQ-EOTF and it will 'hard clip' the content above to the entered 'Peak Luminance' parameter value.

Below there is a summary of the available post-production monitors for color grading of HDR content in the market; including some prototype models also:



The black level luminance level has been estimated based to the manufacturers published contrast ratio specifications.

Reference monitors used for content color grading are calibrated to follow as best as possible the PQ-EOTF up to the nits they are capable to output and they will 'hard-clip' the nits can't able to reach, without any kind of not tone-mapping applied. The same it's happening with gamut calibration also, there not any gamut mapping applied.

Its recommended the post-production monitors to be calibrated and masters using P3 colorspace with D65 white point, rather than using REC.2020, since P3 is typically the largest realizable and accurate color gamut between different mastering monitors.

While REC.2020 refers to a wider color space that was standardized for UHD HDR video mastering, because most displays are still only capable of smaller gamut's than REC.2020, it is being used as a 'container' for smaller gamut's like P3-D65.

When the post production monitors are set to REC.2020, this requires a conversion to their native display primaries, and the methods for doing so can vary between monitors (gamut mapping vs. clipping, for example). For this reason, its most consistent and efficient to calibrate and encode using the P3-D65 colorspace. In that case, the studio will convert the content to BT.2020 later in their workflow.

But as you can see to the summary below, there studios where they used REC.2020 or custom gamut/colorspace coordinates also:



As for the most HDR10 titles currently available to the market, post production studios has been used the Sony BVM-X300 RGB OLED Reference Broadcast Monitor, as there unit-per-unit variations for luminance output capabilities and for gamut coverage also, these broadcast monitors are capable to reach up to ~1100 nits calibrated peak output, so some facilities are calibrating them for 1000 nits, while others for 1100 nits (like 20th Century Fox), for that reason there available a few titles mastered with 1100 nits ('Mastering Display Color Volume -> Maximum Display Luminance' value).

When we say '1000 nits monitor used', doesn't mean that the movie will have up to 1000 nits luminance levels, it can have much lower or much higher, as it's up to the colorist decision if he will 'hard clip' or leave un-clipped the content above 1000 nits, looking the waveform and RGB histogram of the content.

While tracking PQ-EOTF to the max nits of each LG 2019 OLED TV is capable to output; without using any tone-mapping but doing 'hard-clip'; is more accurate way to preserve the creative intent with a more authentic way, many users will prefer the tone-mapping capabilities which can offer a better picture for the average consumer eyes.

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post #3 of 19 Old 09-26-2019, 06:06 AM - Thread Starter
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How to upload custom PQ Curve parameters data values to the LG 2019 OLED TV's?


After you have created a connection of DeviceControl Interface with the LG 2019 OLED TV using these instructions, then:

1) Select the LG 2019 PQ Curve Upload Template from your 'local' and click on 'Connect', the green button on the top bar:



...it should change to red and say 'Disconnect'.

2) Click the 'Send Icon' on 'Request Pin' to request from LG 2019 OLED TV to show the pin number:



3) LG 2019 OLED TV should pop-up a window with a pin number. Enter it on 'Set Pin' input box and click the 'Send Icon'.



4) Click on 'Enable Calibration' checkbox.



...After calibration will be enabled, the Picture Profile selection will appear:



5) Select the Picture Profile (HDR Cinema, HDR Technicolor Expert or HDR Game) you want to use for sending custom PQ Curve parameters:



After you have selected the Picture Profile you prefer to upload custom PQ curves, you can apply the 7 parameters for custom HDR10 Tone mapping to the values you desire.



6) Enter the specific parameter value you want. You can enter value via keyboard or by clicking to '+' or '-' icons and then click to 'Pencil' Icon to apply your parameter value.



7) When you will have entered all your custom PQ Curve parameter values, click to 'Send Icon' for the 7 parameter values to be transferred to the TV Tone Mapping engine.



8) Click on 'Enable Calibration' checkbox to disable the connection with the LG 2019 OLED TV for the procedure to complete.



Note: 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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post #4 of 19 Old 09-26-2019, 06:24 AM - Thread Starter
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What is the 'Peak Brightness' setting and how it’s affecting the LG OLED TV luminance output?

LG 2019 OLED TV's feature a 'Peak Brightness' control. The default setting for HDR10 mode of Peak Brightness is 'High', which will provide the highest panel peak luminance output when you will use it with custom PQ curve parameters values.



Peak Brightness control provide the capability to change the amount of White sub-pixel 'boost'.

The White sub-pixel can't be permanently disabled when you will set Peak Brightness at 'Off', but setting to 'Off' it will significantly reduce the panel peak luminance output.

While the peak output will be reduced, the color accuracy will be increased because saturation distortion will be reduced in result of less color reproduction errors.

In a display, a 'pixel' is a collection of individual display elements that, when taken together, are able to reproduce the full color range of which the display is capable.

The LG OLED WRGB displays implements white with target peak luminance higher than maximum luminance using three-color subpixels (W/R/G, B/W/R, G/B/W or R/G/B) among four-color (W/R/G/B) subpixels in order to adjust a color temperature.

In order to enhance the luminance of the LG OLED TV especially for HDR mode, an additional a W sub-pixel (unfiltered transmitting white light) has been added to the other 3 sub-pixels (RGB) which are filtered.

The unfiltered White sub-pixels are much more efficient than the RGB-subpixels, so efficient drive schemes based to 'White Replacement algorithm' utilize the W primary as much as possible and the RGB primaries as less as possible, by computing and removing/subtracting the neutral luminance from an RGB triad of sub-pixels and transfer/assign it to the W sub-pixel, this method increasing the overall efficiency of the display panel.

One recommendation you can test, when the maximum luminance (Peak Luminance value) of the LG 2019 OLED TV is 800 nits, to track PQ-EOTF as accurately as possible up to 540 nits (540 nits / 800 nits = 0.675). This will require to set the Roll-Off Point @ 68% value.

Another recommendation you can test, for reducing the color saturation distortion because of white sub-pixel 'boosting', is set 'Peak Brightness to 'Off' and then measure the Luminance of the display primary colors, using 10% Window (L32) patches with 100% Luminance level, then sum the Y (luminance) of primaries (Y of Red + Y of Green + Y of Blue) and after the summary, use that number as 'Peak Luminance' parameter value and apply 'hard-clip' by uploading 100% values to all 'Roll-Off Points'.

Doing that, you will preserve the maximum possible color accuracy and minimize any color saturation distortion effect, while you will reduce your peak output and preserve a 'less-HDR-effect' as negative side-effect.

To verify using that method that the display will perform closer to an additive display performance, where the sum of a primary colors luminance will provide the same luminance as White, then you have to re-measure the W,R,G,B at peak luminance to verify that each primary can deliver the appropriate luminance level for your peak White brightness measurement.

To pass this test, the sum of the luminance of R, G and B will be approximately equal to the luminance of White.

When the White luminance level is higher than the sum of the primaries then the display is not performing as additive.

When the White Luminance level is lower than the sum of the primaries, this likely means that there some luminance compression happening (e.g. power saving/management).

The accepted tolerance will be a luminance discrepancy of -1 to 5%.

EBU TECH 3320 (Version 4.1 - September 2019) - User Requirements for Video Monitors in Television Production, defines the technical characteristics for video broadcast monitors used in a professional TV production environment for evaluation and control of the images being produced.

From Version 4.0, its been added a section dedicated to High Dynamic Range and Wide Color Gamut for UHD and 1080P HD Monitors.

That section splits Grade 1 HDR monitors into two types: Grade 1A HDR and Grade 1B HDR. A Grade 1A monitor can accurately reproduce all aspects of the standard it was designed to display.

A Grade 1B monitor may not be capable of reproducing the full range of colour or brightness defined in a standard, but will otherwise fulfil all the requirements of a Grade 1A monitor.

This novel approach was taken to bridge the gap between what a video standard may define and what monitors currently available on the market are able to reproduce.

Grade 1B HDR monitors require ≥1000 nits peak white, but they can have reduced Gamut and limited brightness specifications. Grade 1B HDR may be withdrawn at a future date.

When a Grade 1B monitor is unable to correctly display an input signal, e.g. it cannot physically display colors conveyed in an ITU-R BT.2100 signal, it shall by default apply a hard clip of the linear display signals to the available color volume whilst maintaining the ITU-R BT.2100 white point, rather than applying a soft clip (roll-off).

For Grade 1A HDR PQ or the Grade1B HDR PQ monitors, a 199.2cd/m2 (code value 592, 10-bit full range) full screen, uniform field input signal shall be displayed without power limiting.

LG 2019 OLED TV's unfortunately can't meet these specifications, and can't be recommended for color grading of HDR content.

But LG 2019 OLED TV's can be used as client view (review screening), on set, VFX, editing, or QC applications.

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How 'AI Brightness' is working and why it has to be disabled when custom PQ Curves are used?

LG 2019 OLED TV's featuring the 'AI Brightness' function, to optimize brightness based on ambient light conditions of the viewing environment illuminance level.

AI Brightness feature is located in Picture -> Picture Mode Settings -> Picture Options section of the HDR Cinema Home Picture Mode.



This feature will improve the visibility of the content dark areas by recognizing ambient illumination for applying further adjustment to the HDR tone-mapping.

AI Brightness feature is not recommended to be enabled when you will use custom PQ Custom parameters feature and you want to view content in a dark (light controlled) room 'reference' environment.

How AI Brightness works?

An HDR10 content is encoded using a perceptual quantizer opto-electrical transfer function (hereinafter, PQ-OETF) defined by the society of motion picture and television engineers (SMPTE) ST. 2084 and has a high dynamic range of 0 to 10000 nits.

LG OLED TV needs to perform an image processing procedure using a perceptual quantizer electro-optical transfer function (PQ-EOTF) defined in SMPTE ST. 2084, in order to display an HDR10 content.

However, since the PQ-EOTF used in the image processing procedure of the LG OLED TV is derived in a dark room, a just-noticeable difference (JND) in a bright room is not applied.

When the LG OLED TV displays an HDR10 content subjected to the image processing procedure using the PQ-EOTF in a bright room, a luminance saturation phenomenon wherein gray-level banding is caused in a high luminance region of an image is generated, deteriorating visibility.

When the viewing room illuminance information sensed through an illuminance sensor is received, a perceptual quantizer electro-optical transfer function (PQ-EOTF) is adjusted for improving visibility.



The LG OLED TV image processing module will adjust the PQ-EOTF according to illuminance to adjust luminance of the HDR10 content.

In other words, the image processing module converts the HDR content into luminance information using the PQ-EOTF and adjusts the luminance information by applying an illuminance-based weight.

As viewing room illuminance increases, the weight increases and thus luminance of the HDR10 content increases. Therefore, visibility of the HDR10 content displayed on the display device is improved.

The EOTF processor converts the gray level information of the received HDR image into luminance information and adjusts the luminance information by applying a weight according to illuminance information received from the illuminance sensor.

The following flowchart illustrating that HDR image processing method:



The LG OLED TV may display the output luminance of the input gray level along the basic PQ-EOTF curve and represent the gray level up to the target peak luminance of the display. In the case of applying the illuminance-based weight to adjust the PQ-EOTF curve, as the illuminance-based weight increases, the PQ-EOTF curve is shifted to the left.

In the PQ-EOTF1 curve shifted based on the illuminance-based weight, it can be seen that the output luminance according to the gray level increases as compared to the basic PQ-EOTF curve.

If the high-luminance rate of occupancy of the pixels exceeding the target peak luminance of the LG OLED TV in the HDR10 content exceeds the threshold, the target peak luminance gradually increases from the target peak luminance to the maximum luminance along a roll-off curve without saturation of the high gray level part corresponding to high luminance equal to or greater than the target peak luminance, thereby increasing distinguishability of the gray level of the HDR image and reducing luminance saturation.

The following diagram showing an image processing result of an HDR display device according to an embodiment using a PQ-EOTF curve:



The EOTF processor multiplies the luminance information of each subpixel by the weight according to the illuminance information to perform adjustment. A look-up table (LUT) having a weight changed according to illuminance section information received from the illuminance sensor is stored in the memory used in the image processing module.

The EOTF processor selects a weight according to the illuminance section information from the LUT, multiplies the luminance information of each subpixel by the selected weight and adjusts the luminance information according to illuminance. As illuminance increases, the weight increases and thus luminance increases. Even when the illuminance is high, visibility is improved.

The luminance analyzer analyzes the luminance information of the HDR content received from the EOTF processor and calculates the high-luminance rate of occupancy of the high-luminance part having target peak luminance or more of the LG OLED TV in the HDR10 content.

The luminance analyzer analyzes the luminance information of the HDR10 content at least in frame units and counts the number of high-luminance pixels having target peak luminance or more in the content.

The luminance analyzer calculates the ratio of the number of high-luminance pixels to the total number of pixels and outputs the high-luminance rate.

The luminance analyzer may detect a maximum value of the luminance values of the sub-pixels of each pixel as a representative value of each pixel, compare the representative value of each pixel with the target peak luminance, and count pixels having the representative value equal to or greater than the target peak luminance as high-luminance pixels.

The LG OLED TV may adjust the luminance of the HDR10 content according to illuminance and increase the luminance of the high-luminance part when the high-luminance rate of the adjusted HDR10 content is equal to or greater than the threshold, thereby increasing gray level distinguishability of the HDR content and reducing luminance saturation. Therefore, it is possible to improve visibility and image quality.

The LG OLED TV may display the HDR10 content with the target peak or less when the high-luminance rate of the HDR10 content adjusted according to illuminance is less than the threshold, thereby improving visibility and maintaining power consumption.
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post #6 of 19 Old 10-02-2019, 02:37 AM
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Thanks Ted for the detailed info! Do you have anything similar about LG's dynamic tone mapping? (can be older models as well)

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post #7 of 19 Old 10-02-2019, 02:43 AM - Thread Starter
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Thanks Ted for the detailed info! Do you have anything similar about LG's dynamic tone mapping? (can be older models as well)
I haven't investigated with more detail the LG's Dynamic Tone Mapping, the only I know is that dynamically generated after analysis of signal peak and histogram information on a frame by frame basis.

But all the info you see there, the same way they are working the 2018 models, just they are using the default tone mapping values, as you can't change them.

LG has provide special firmware to their special partners which is adding custom PQ curve upload to 2018 models but that FW will never be available to consumers.
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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 2: 60%
Metadata Point 3: 10000 nits
Roll-Off Point 3: 50%
Ted, do you know which values are used on B8/B9?

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Ted, do you know which values are used on B8/B9?
Its the same 'default' values for all 2018/2019 models.
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Its the same 'default' values for all 2018/2019 models.
Thanks, it's just strange, because the 19. point of the HDR10 WB is different between B8 and C8.

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post #11 of 19 Old 10-10-2019, 07:53 AM - Thread Starter
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Thanks, it's just strange, because the 19. point of the HDR10 WB is different between B8 and C8.
The points (with 10-bit code) are not actually PQ-EOTF code values points, but gamma based points, then its added the PQ-EOTF tracking of tone-mapping.

For that reason HDR10 patterns you display with these codes are not affect exact the codes the LG menu is saying, its the main reason why banding introduced when you tweak a lot the 20-Point RGB balance values.
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Hi Tedd, if my peak brightness is 720 nits, what would be you recommended settings?
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Hi Tedd, if my peak brightness is 720 nits, what would be you recommended settings?
What TV model do you have?

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Lg c9 55 inch
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Lg c9 55 inch
Ideally, for the most accurate calibration and for keeping as high as possible the artistic intent of the content, any tone-mapping should be disabled, to let the display follow the PQ-EOTF up to the maximum nits the panel can output. This can be performed by uploading to all 'Roll-Off Point' parameters to 100% values. Doing this, the panel will track as best as possible the PQ-EOTF and it will 'hard clip' the content above to the entered 'Peak Luminance' parameter value.

While the picture it will look clipped at highlights, which can be only a few movie moments, the rest of the movie will look more 'correct'.

Most of the people will not like that setting.

For example if you spend 30-40K$ to get a reference post-production monitor which has peak output 1000 nits, when you will watch a 4000 nit movie it will hard clip at 1000 nits, so you do the same with your TV just at lower nits

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post #16 of 19 Old 10-14-2019, 02:13 PM
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Ideally, for the most accurate calibration and for keeping as high as possible the artistic intent of the content, any tone-mapping should be disabled, to let the display follow the PQ-EOTF up to the maximum nits the panel can output. This can be performed by uploading to all 'Roll-Off Point' parameters to 100% values. Doing this, the panel will track as best as possible the PQ-EOTF and it will 'hard clip' the content above to the entered 'Peak Luminance' parameter value.

While the picture it will look clipped at highlights, which can be only a few movie moments, the rest of the movie will look more 'correct'.

Most of the people will not like that setting.

For example if you spend 30-40K$ to get a reference post-production monitor which has peak output 1000 nits, when you will watch a 4000 nit movie it will hard clip at 1000 nits, so you do the same with your TV just at lower nits
I have done this.

- Rich
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Quote:
Originally Posted by ConnecTEDDD View Post
Ideally, for the most accurate calibration and for keeping as high as possible the artistic intent of the content, any tone-mapping should be disabled, to let the display follow the PQ-EOTF up to the maximum nits the panel can output. This can be performed by uploading to all 'Roll-Off Point' parameters to 100% values. Doing this, the panel will track as best as possible the PQ-EOTF and it will 'hard clip' the content above to the entered 'Peak Luminance' parameter value.

While the picture it will look clipped at highlights, which can be only a few movie moments, the rest of the movie will look more 'correct'.

Most of the people will not like that setting.

For example if you spend 30-40K$ to get a reference post-production monitor which has peak output 1000 nits, when you will watch a 4000 nit movie it will hard clip at 1000 nits, so you do the same with your TV just at lower nits [IMG class=inlineimg]/forum/images/smilies/wink.gif[/IMG]
I have done this.

- Rich
Thank you Tedd.
How does this look Rich, do you prefer it to the standard setting?
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Hi Tedd, do you have perhaps a good compromise between accuracy and pleasing image?

Would you dynamic tone mapping on or off?
Or would you use custom tone mapping and have it off ?
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Hi Tedd, do you have perhaps a good compromise between accuracy and pleasing image?

Would you dynamic tone mapping on or off?
Or would you use custom tone mapping and have it off ?
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 and entire custom tone mapping upload parameters will be bypassed.

When Dynamic Tone Mapping is disabled 'Off', the LG TV will use the custom HDR10 tone curve parameters you will upload (or use the default if you don't uploaded anything).

The lower the percentage you will set, means the higher the deviation from PQ-EOTF tracking, but less compression.

There no custom setting which work best with all movies.

The example I posted to you above explains a lot, since if you buy a post-production monitor (1000/2000/3000 nits), all these monitors perform hard clip to their peak output, they don't apply any tone-mapping:


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