For a Better HDR Gaming Experience- Best Practice Recommendations for Game HDR Creation
Version 1.1
HDR Gaming Interest Group
July 2019
This is a document made available by Microsoft Corporation and Sony Interactive Entertainment. The technology embodied in this document may be subject topatent rights, including patents owned by such companies. No patent license, either implied or express, is granted to you by this document. This document isprovided on an as-is basis without any warranty whatsoever(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

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Background•

Game platforms support High Dynamic Range (HDR)•XBOX One S, XBOX One X•
PlayStation® 4, PlayStation® 4 Pro•Windows 10•

Major game publishers have already released HDR games.
•More than 100 HDR games were released so far on the above game platforms.

•HDR is a great technology, but consumer reactions are not always positive to HDR games. Games are different from other media
content like movies, because they are interactive, immersive and competitive.

•HDR Gaming Interest Group, with participation of leading companies from the entertainment, game and TV industries, analyzed
issues behind the negative reactions from consumers about HDR games and recommend the guidelines for HDR game production
as outlined in the following pages. In sum, the core element of the recommendation is to produce an HDR game that parameterizes
its tone mapper when given information about an HDR display's tone mapper. This will compensate for the variance in how displays
handle HDR.

•As described in later pages, certain aspects of these recommendations may be further elaborated based on knowledge
accumulated through experiences in HDR game production. HDR Gaming Interest Group also anticipates these recommendations
will be implemented more easily with support from neighboring technological standards (e.g. some aspects of parameter exchange
between game consoles and TVs/PC displays can be automated with CTA and HDMI Forum standards).
(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reservedChallenges••

HDR displays cannot yet reproduce the full extent of luminance andcolor as specified in BT2100 PQ. Also, e.g. games using physical based
rendering (PBR), render into an unconstrained linear space thatexceeds BT2100 PQ. For example, a sun could be rendered muchbrighter than 10,000 nits.
To make effective use of its display panel capabilities, an HDR display
uses tone mappers to map the original color volume of source
content to the color volume of its display panel (“Display mapping”)•Different HDR displays handle display mapping in different ways,
resulting in visual differences of the same source HDR content.

•TV manufacturers, based on their own research and development,
design displays to bring the best picture quality in their own ways.
Differences in their design philosophy may be a cause of the variancein HDR handling.

•Such variance unfortunately sometimes results in inconsistency inconsumers’ game play.

Color volume conversion(Display mapping)BT.2100 PQ
Container

4000

1000

Displaypanelcapability(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Typical Undesirable User Experience – Details in bright areas, critical togameplay, may be lost.

Some players can see the right turn after the tunnel, but other players can’t.
(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Typical Undesirable User Experience – Details in bright areas, critical togameplay, may be lost.

Some players can see the right turn after the tunnel, but other players can’t.
(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guiding Principles
The following are the guiding principles in identifying the best practice recommendations.
1.

Acknowledge difference
There is wide variance in how HDR content is processed in HDR displays, and the assumption that “displays
perform exactly the same” cannot be taken. Each display’s HDR capability should be utilized to the full extent.

2.

Consistent and fair game play
Game design creative intent (e.g. a zombie appearing from the dark, an enemy shooter silhouetted in blindinglight) needs to appear the same for consistent game playability, regardless of display performance difference.

3.

Forward compatible
The existing HDR game experience should not be deteriorated, but stable or even enhanced with theimprovement of future HDR display performance.

4.

Easy to use and practical for developers and consumers
Practical and easy-to-use means must be prepared for game developers and consumers. For example, any
processing should not consume resources that may affect real-time processing, and complicated manual setup
operations (e.g. in-game calibration) should be avoided.
(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reservedOverview of the best practice recommendations
These best practice recommendations consist of the following elements. The best practice recommendations asa whole aim to achieve HDR rendering of game content as game creators intend and assure consistent userexperiences with regards to objects critical to game play.
1.

HDR games implement parameterized tone mappers that can render critical primary objects within acertain range of luminance to ensure consistent game play (“Primary HDR range”).

2.

HDR displays preserve gradation within the Primary HDR range while in Game mode. Display
manufacturers provide to game console manufacturers information relating to tone mapping toaccommodate Games to leverage the full HDR capabilities of their HDR displays within the Primary HDR
range. For PC monitors, recommendations based on standardization activities in the PC environment
should still be incorporated.

3.

Game consoles provide APIs to games in order to retrieve information relating to tone mapping to preserve
gradation within the Primary HDR range. Game consoles also provide to consumers a system calibration
which can override tone mapping information provided by display manufacturers, so that consumers cancustomize game play experience or optimize for different lighting environments.

(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

System Overview of the Best Practice Recommendations••Preserve gradation for the Primary HDR range.
Provide tone mapping information about its
Primary HDR range to game consolemanufacturers.

•••

Model names, tone map information
are stored to database.
Provide calibration screen to user.
Provide final tone map information
about Primary HDR range to Game.
DataBase

Luminance [nit]•Apply tone mapping information for
the Primary HDR range to Game’s
parameterized HDR tone mapper.
Critical objects are rendered within
Primary HDR range.

Fig. PQ input signal

10000
3000
2500
2000
1500
1000
500
0

•

Non-optimized
image

00

255
256

511
512

767
768

Optimized
image1023
1024

Code Value (10bit)
Example: This display’s Primary HDR range extends to2000 nits and can preserve the gradation up to 2000 nits.

Starting point of system calibration isdisplay’s Primary HDR range.

(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

System Overview of the Best Practice Recommendations
Guideline to HDR Display Manufacturer••

Preserve gradation for the Primary HDR range.
Provide tone mapping information about its
Primary HDR range to game consolemanufacturers.

Guideline to HDR Game Console Manufacturer•••

Model names, tone map information
are stored to database.
Provide calibration screen to user.
Provide final tone map information
about Primary HDR range to Game.
DataBase

Luminance [nit]••Apply tone mapping information forthe Primary HDR range to Game’s
parameterized HDR tone mapper.
Critical objects are rendered within
Primary HDR range.

Fig. PQ input signal

10000
3000
2500
2000
1500
1000
500
0Guideline to HDR Game Developer

Non-optimized
image

00

255
256

511
512

767
768

Optimized
image

1023
1024

Code Value (10bit)
Example: This display’s Primary HDR range extends to2000 nits and can preserve the gradation up to 2000 nits.

Starting point of system calibration isdisplay’s Primary HDR range.

(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Terminology

Luminance [nit](1) MaxFullFrameToneMapLuminance (MaxFFTML)
The value indicates max PQ Code Value which a display’s tone mapper can preserve bright detail.
The value indicates the max value in 100% (full frame) area of display.
(2) MaxToneMapLuminance (MaxTML)
The value indicates max PQ Code Value which a display’s tone mapper can preserve bright detail.
The value indicates the max value in 10% area of display.
(3) MinToneMapLuminance (MinTML)
The value indicates minimum PQ Code Value which a display’s tone mapper can preserve dark detail.
The value indicates the min value in 10% area of display.
(4) Primary HDR range
This range contains code values between MinTML and MaxFFTML. Displays should preserve gradations in this range
where Games can render objects critical to game play.
(5) Extended HDR range
This range contains code values between MinTML and MaxTML. Displays should preserve gradations in this rangefor up to 10% of the display area. This range may be usable to games for critical game play objects within thissmaller area. MinTML
4000
3500
3000
2500
2000
1500
1000
5000MaxFFTML

MaxTML

Extended HDR range
Primary HDR range
0256 Code Value (10bit) 512
255
511

Code value (10bit)

768
767

1024
1023

Display Category Definitions
Category 1 Display

Category1• MinTML = 0.1nits• MaxTML= 600nits

Category 2 Display

Category 3 Display

Category2• MinTML = 0.1nits• MaxTML = 1000nits

Category3• MinTML = 0.1nits• MaxTML = 4000nits

Category 4 Display

Category4• MinTML = 0nits• MaxTML = 10000nits• Display Categories are used when full luminance values are not available.
• The Categories define default luminance values.
• In all Categories, MaxFFTML=600 nits.

(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guideline to HDR Game Developer
Leverage full capability of HDR displays and ensure consistent game play
Game retrieves MaxFFTML, MaxTML and MinTML about attached HDR display
Game renders objects critical to gameplay in either the Primary or Extended HDR Range
Game uses Primary HDR range when critical objects cover very large area of screen, and the Extended HDR
range when covering a smaller area of the screen

Luminance [nit]

1.
2.
3.

4000
3500
3000
2500
2000
1500
1000
500
0

MinTML

Extended HDR range

MaxFFTML
MaxTMLPrimary HDR range
00

256 Code Value (10bit) 512
255
511

Code value (10bit)

768
767

1024
1023

Guideline to HDR Game Developer
Examples of using Primary HDR Range and Extended HDR Range
Example 1•Game knows it will never render very bright objects critical to game play over the full area of the screen•Game adjust its tone mapper to make use of the Extended HDR range
Example 2•
Game knows it will very rarely render very bright objects critical to game play over the full area of the screen, e.g. only 1 or 2
seconds in total during an hour of game play•
Developer opts for simplicity and accepts the possibility that some HDR displays might clip in very rare occasions, and adjusts
game’s tone mapper to make use of the Extended HDR range
Example 3•
Game knows it will often render very bright objects critical to game play over the full area of the screen•
Game interpolates between the Primary HDR range and the Extended HDR range, based on histogram information aboutluminance values, which is already determined at runtime for calculating bloom effects(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guideline to HDR Display Manufacturer
1.

Provided MaxFFTML, MaxTML and MinTML values are determined by running the development version of theHDR game console system calibration screen described in this document with HDR display set to game mode.
Slider values for this version are shown, whereas in the consumer version, they are not. Using this tool also
helps the manufacturer to determine the most-accurate Category to indicate instead of the actual values ifthey prefer.

2.

HDR display manufacturer communicates with HDR game console manufacturer to provide the following
information about the HDR display.
a. Display identification scheme to differentiate models with different parameters
b. Display Parameters•MaxFFTML, MaxTML, and MinTML; or•Category Designation (which provides default parameters)

3.

In operation, the HDR display should preserve details and gradation of objects within the Primary HDR andExtended HDR ranges as defined in this document.

(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guideline to HDR Game Console Manufacturer

1. HDR game console manufacturer communicates with display manufacturer to createdatabase
2. Identify the connected HDR display
3. Query database for HDR display’s tone mapper luminance values
4. Optionally present calibration screen to consumer to customize or optimize tone
mapper luminance values
5. Provide tone map luminance values to game through API(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guideline to HDR Game Console Manufacturer

1. Communicate with HDR display manufacturers to obtain(a) Display identificationi. How HDR game console can identify the display (e.g. EDID model ID etc.).
ii. Alternate identification scheme when repeaters are used.
(b) Display parameters
i. MaxTML, MinTML and MaxFFTML; orii. Category Designation.

2. Game console should have database of Display IDs and display parameters.
Display ID: XX-XX

Display ID: XX-XX
MaxFFTML : 1000
MaxTML : 1200
MinTML : 0.1
Display ID: YY-YY…

(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reservedGuideline to HDR Game Console Manufacturer
Default values are used.
MaxFFTML : 600nits
MaxTML : 1000nits
MinTML: 0.1nits

A display cannot be identified
by game console

No information

Can be identified by game console Example:
With full information
MaxFFTML : 1200
MaxTML : 1500
MinTML : 0.08

Can be identified by game console
Category information only available
Example:Category 2 display

Example:Start point of calibration is
MaxFFTML : 1200
MaxTML : 1500
MinTML : 0.08

Example:Start point of calibration is Category 2
MaxFFTML : 600
MaxTML : 1000
MinTML : 0.1(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

startGuideline to HDR Game Console Manufacturer

Game console sets the fields asdetermined by the flowchart.

Default values are used. MaxFFTML:
600nits, MaxTML : 1000nits andMinTML: 0.1nits

Is display the same?
(Can use previous values?)

Previous values determine
MaxTML, MinTML and MaxFFTML
YES

Database parameters determine
MaxTML, MinTML and MaxFFTML

NO
Database Category determines
MaxTML, MinTML and MaxFFTML
Can console identify
connected display?

NOShow calibration screento user?

YESCategory

MinTML (nits)

MaxTML (nits)

10.1

600

20.1

1000

30.1

4000

40.0

10000

MaxFFTML is 600nits throughout the Categories

Is display in the database?

NO(new model)

YES
Are full Parameters
stored in database?

NO(only Category)

YES

YES
Execute calibration.
MaxTML, MinTML and MaxFFTML
are overridden by the settingGame console provides
MaxTML, MinTML and MaxFFTML
to game by API

ENDNO

Guideline to HDR Game Console Manufacturer

Provide 3 types of calibration screens to user.

(1) MaxFullFrameToneMapLuminance•••

The value indicates max luminance in 100% area of display.
Max 12 bit BT.2100 PQ Code Value at which display perceptually preserves the checker box.
Adjust slider until gray squares just disappear.

PQ Max Codefor 10000 [nit]

10000

Input
Signal0(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guideline to HDR Game Console Manufacturer

Provide 3 types of calibration screens to user.

(2) MaxToneMapLuminance•••

The value indicates max luminance in 10% area of display.
Max 12 bit BT.2100 PQ code value at which display perceptually preserves the checker box.
Same operation as for MaxFFTML. Expect MaxTLM≠MaxFFTML.

PQ Codefor 1 [nit]10000

PQ Max Codefor 10000 [nit]Input
Signal0(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Guideline to HDR Game Console Manufacturer

Provide 3 types of calibration screens to user.

(3) MinToneMapLuminance•••

The value indicates min luminance in 10% area of display.
Max 12 bit BT.2100 PQ code value at which display perceptually preserves the checker box.
Adjust slider until gray squares just disappear.

PQ Codefor 1 [nit]10000

PQ Min Codefor 0 [nit]Input
Signal0(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Example 1 – The ideal scenario
TV Manufacturer “ABC”
1. Develop new TV, model “XYZ-123”
2. Attach TV to Game console
3. Run game console’s system calibration and determine MaxFFTML = 1500 nits, MaxTML = 1500 nits, MinTML = 0.01 nits
4. Communicate to game console manufacturer: EDID ID “ABC-XYZ-123”, 1500, 1500, 0.01
Game Console Manufacturer
1. Update database with: “ABC-XYZ-123”, 1500, 1500, 0.01
Consumer
1. Buy new TV “ABC” model “XYZ-123”
2. Install and run GameGame
1. Call game console API
2. Game console determines “ABC-XYZ-123” from TV’s EDID
3. Game console queries database and returns from its API: MaxFFTML = 1500, MaxTML = 1500, MinTML = 0.01
4. Adjust parameters of tone mapper between 0.01 and 1500 nits(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Example 2
TV Manufacturer “DEF”
1. Develop new TV, model “TUV-456”
2. Attach TV to game console
3. Run game console’s system calibration and determine MaxFFTML = 2000 nits, MaxTML = 2000 nits, MinTML = 0.05 nits
4. Uncomfortable to communicate 2000, 2000, 0.05 to game console manufacturer, decides to use Category 3 instead
5. Communicate to game console manufacturer: EDID ID “DEF-TUV-456”, Category 3
Game console manufacturer
1. Update database with: “DEF-TUV-456”, Category 3
Consumer
1. Buy new TV “DEF” model “TUV-456”
2. Install and run gameGame
1. Call game console API
2. Game console determines “DEF-TUV-456” from TV’s EDID
3. Game console API returns default tone map information for Category 3: MaxFFTML = 600, MaxTML = 4000, MinTML = 0.1
4. Adjust parameters of tone mapper between 0.1 and 4000 nitsTV
1. Receive PQ values between 0.1 and 4000 nits
2. TV’s tone mapper only maps to 2000 nits, so clips information above 2000 nits(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved

Example 2 - continued
Consumer
1. Not satisfied with HDR game
2. Run game console’s system calibrationGame console
1. Determine “DEF-TUV-456” from TV’s EDID
2. Query database and determine TV is Category 3
3. System calibration use default start values for Category 3: MaxFFTML = 600 nits, MaxTML = 4000 nits, MinTML = 0.1 nits
4. Consumer adjust values to: MaxFFTML = 2000 nits, MaxTML = 2000 nits, MinTML = 0.05 nits
5. Store new values for TV locallyConsumer
1. Run game again
Game
1. Call game console API
2. Game console determines “DEF-TUV-456” from TV’s EDID
3. Game console returns locally stored calibrated values from its API: MaxFFTML = 2000, MaxTML = 2000, MinTML = 0.05
4. Adjust parameters of tone mapper between 0.05 and 2000 nits(c) Microsoft Corporation and Sony Interactive Entertainment, all rights reserved