Understanding Tone Mapping Basics
If HDR looks washed out, too dark, or inconsistent, tone mapping is the process that adapts the image to the display. HDR tone mapping may happen on the display or during conversion: HDR-to-SDR compresses luminance, while inverse SDR-to-HDR processing expands it.
What is Tone Mapping in Simple Terms?
Tone mapping is the process of translating brightness values from a wide range into a narrower range that your screen can actually display.
Think of it this way: a real-world scene might have a brightness range from deep shadow (nearly zero light) to direct sunlight (millions of times brighter). HDR cameras capture much of this range, but a consumer TV can reproduce only part of it. Tone mapping bridges that gap by intelligently compressing the brightness values so that highlights remain bright, shadows retain detail, and mid-tones look natural.
The key word here is "intelligently." Simply clipping values above or below a threshold would destroy detail. Instead, tone mapping uses mathematical curves and algorithms to redistribute brightness in a way that preserves the perception of contrast and detail across the entire image.
Why HDR Content Needs Tone Mapping
HDR content is captured or mastered with a dynamic range far exceeding what most displays can reproduce. Here is why tone mapping is essential:
- Dynamic range mismatch: HDR content can contain luminance values outside the target display's range. Without tone mapping, highlight or shadow detail may be lost.
- Color preservation: Simply compressing brightness would shift colors. Tone mapping protects color accuracy and vibrancy during the compression process.
- Perceptual accuracy: Human eyes adapt to different light levels naturally. Good tone mapping mimics this adaptation, producing results that look natural rather than artificial.
- Device compatibility: Different TVs, monitors, projectors, and phones have vastly different brightness capabilities. Tone mapping adapts HDR content to each specific device.
How Tone Mapping Works
At a technical level, tone mapping applies a transfer function (also called a tone curve) that maps input luminance values to output luminance values. The process typically involves three steps:
- Luminance extraction: The algorithm analyzes the brightness distribution of the HDR content, identifying the range of luminance values present.
- Curve application: A mathematical function compresses the luminance range. This curve is designed to preserve contrast in the most perceptually important areas while compressing extreme highlights and shadows.
- Color reconstruction: After luminance adjustment, color values are recalculated to maintain accurate hue and saturation, preventing color shifts that would make the image look unnatural.
The specific curve used determines the visual character of the result. A gentle curve preserves more highlight detail but may look slightly flat, while an aggressive curve creates more contrast but risks clipping.
Static vs Dynamic Tone Mapping
Not all tone mapping works the same way. The two main approaches, static and dynamic, differ significantly in how they handle varying content. These labels can describe content metadata or display processing, which are not the same mechanism. Dolby Vision and HDR10+ carry dynamic metadata, while a TV can still analyze scenes dynamically when playing HDR10 with static metadata.
What is Static Tone Mapping?
Static tone mapping applies a single, fixed brightness and contrast curve to the entire video, game, or image sequence. HDR10 carries static mastering metadata for the program, but a display may still analyze scenes and apply its own dynamic processing.
How it works: In a static mapping workflow, one set of parameters (brightness curve, contrast level, gamma adjustment) is applied consistently to every frame.
Advantages:
- Simple and fast processing
- Consistent, predictable playback across devices
- Lower hardware requirements
Limitations:
- Cannot adapt to scene-by-scene brightness changes
- Bright scenes may appear washed out while dark scenes lose shadow detail
- A single curve must compromise between different scene types
What is Dynamic Tone Mapping?
Dynamic tone mapping adjusts parameters in real time, optimizing tone mapping per scene or even per frame. Dolby Vision and HDR10+ can carry dynamic metadata, while a TV may also analyze scenes and adjust its tone curve through display-side processing without relying on dynamic metadata.
How it works: The display can analyze brightness, contrast, and color information to adjust the tone curve as scenes change, while compatible Dolby Vision or HDR10+ playback can also use scene- or frame-level metadata. A dark interior scene can receive a different curve than a bright outdoor scene.
Advantages:
- Can preserve more detail as scene brightness changes
- Can adjust contrast and color handling by scene
- Adapts automatically to widely varying scene content
Limitations:
- More computationally demanding
- Available behavior depends on the content, display, and selected mode
- Implementation quality varies between manufacturers
Static vs Dynamic Tone Mapping: Comparison Table
| Feature | Static Tone Mapping | Dynamic Tone Mapping |
| Adjustment | Fixed curve for entire content | Adaptive per scene/frame |
| Metadata relationship | HDR10 carries static metadata | Display analysis or dynamic metadata |
| Detail Preservation | May lose highlight/shadow detail | Adjusts for changing scenes |
| Consistency | Stable curve throughout | Curve changes with content |
| Processing | Lower requirements | Higher processing power |
| Typical Fit | Predictable, consistent mapping | Scenes with varied brightness |
Static mapping can suit workflows that prioritize a consistent curve, while dynamic mapping can better accommodate large brightness changes between scenes. The appropriate choice depends on the content, display behavior, calibration, and viewing preference.
Tone Mapping Algorithms Explained
Tone mapping algorithms fall into two fundamental categories: global operators and local operators. Understanding the difference helps you appreciate why the same HDR image can look vastly different depending on which algorithm processes it.
Global Tone Mapping Operators
Global (spatially uniform) operators apply the same mapping function to every pixel in the image, regardless of its position or the brightness of surrounding pixels.
How it works: A single tone curve is calculated based on the overall luminance statistics of the image (such as average brightness, maximum brightness, and histogram distribution). Every pixel is then mapped through this same curve.
Advantages:
- Very fast and computationally efficient
- Easy to implement in hardware
- Produces consistent, predictable results
- Avoids the neighborhood-based halo risk associated with local operators
Limitations:
- May produce flat-looking images with reduced local contrast
- Cannot preserve fine details in both bright and dark regions simultaneously
- A single curve must compromise across the entire brightness range
Local Tone Mapping Operators
Local (spatially varying) operators adapt the tone mapping for each pixel based on its neighborhood, considering the brightness and contrast of surrounding pixels.
How it works: For each pixel, the algorithm calculates a local luminance adaptation based on nearby pixels. This means a bright pixel surrounded by other bright pixels is treated differently from the same brightness pixel in a dark region.
Advantages:
- Can preserve fine details in highlights and shadows
- Can enhance local contrast and textures
- Can produce a more locally detailed result when calibrated carefully
Limitations:
- Computationally expensive
- Can introduce artifacts (halos, ringing) around high-contrast edges if poorly calibrated
- Slower processing, requiring more powerful hardware
Global vs Local Tone Mapping: Comparison Table
| Feature | Global Operators | Local Operators |
| Adjustment | Same curve for all pixels | Pixel-by-pixel adaptation |
| Speed | Very fast | Slower, more demanding |
| Detail Preservation | May reduce local detail | Can preserve local detail |
| Artifacts | No neighborhood-based halo processing | Halo risk near high-contrast edges |
| Visual Effect | Uniform local-contrast treatment | Enhanced local contrast |
| Best Use Case | Real-time gaming, quick preview | Professional editing, cinema |
Popular Tone Mapping Algorithms Compared
Several well-known tone mapping algorithms are widely used across different applications. Here is how they compare:
| Algorithm | Operator or Transform Family | Spatial Behavior | Documented Control or Tradeoff |
| Reinhard | Global or local operator | Global curve or local adaptation | Exposure and white point affect compression |
| ACES output transform | Color-management output transform | Tone scale within the transform | Parameterized Michaelis-Menten curve |
| Filmic (Hable/Uncharted 2) | Global filmic curve | Same curve across the frame | Shoulder compresses bright highlights |
| Drago | Global logarithmic operator | Same mapping across the frame | Bias parameter changes compression |
| Durand (Bilateral Filter) | Local bilateral operator | Base and detail decomposition | Strong local contrast may create halos |
| Mantiuk | Local perceptual operator | Spatial contrast adaptation | Higher processing cost and careful tuning |
Reference: ACES Output Transforms technical documentation, “Tone Mapping,” accessed October 2026.
ACES is a color-management system with output transforms that include tone mapping. Its documented tone scale uses a parameterized Michaelis-Menten curve; ACES is not the name of a single generic global operator.
Reinhard was one of the first widely adopted algorithms and remains popular in photography for its natural-looking results that avoid the over-processed look.
Filmic tone mapping (popularized by Naughty Dog's Uncharted 2) is favored in video games for its ability to handle extreme brightness ranges while maintaining visual punch.
For uniform, predictable processing, a global curve is usually the more practical fit. Choose a local operator when preserving local contrast matters more and the workflow allows careful control of halo artifacts.
Tone Mapping Across Different Use Cases
Tone mapping is not limited to a single industry. It plays a critical role in TVs, gaming, photography, and video production, each with unique requirements.
Tone Mapping in TVs and Monitors
When you watch HDR content on a TV, the display's built-in tone mapping engine adapts the content to match what the panel can actually produce. The result depends on the content metadata, the display's capabilities, and the selected picture mode.
Key points for TV viewing:
- HDR10 uses static metadata, but a TV can still analyze scenes and apply its own dynamic processing
- A Dolby Vision vs HDR10 comparison concerns format metadata, which is separate from a TV's optional dynamic tone mapping setting
- Projectors and lower-brightness displays often require more luminance compression to preserve visible highlight and shadow detail
- Menu labels such as Static, Active, Dynamic Tone Mapping, and HGiG are model-specific rather than interchangeable format names
Recommended settings
On supported LG TVs with an HDR gaming input and Game Optimizer enabled, Dynamic Tone Mapping On, Off, and HGiG are distinct choices. On can suit viewers who prefer a brighter presentation, while a calibrated HGiG workflow can provide more consistent gaming output; HGiG may appear darker, and turning Dynamic Tone Mapping Off is not the same as selecting HGiG. Choose the mode before calibration and keep that mode active afterward so the calibration target remains consistent.
Tone Mapping in Gaming
Gaming presents a unique challenge for tone mapping because the content is generated in real time and scene brightness can change instantly based on player actions.
How games handle tone mapping:
- Modern game engines (Unreal Engine, Unity) apply tone mapping as a post-processing step after rendering
- Most AAA games use ACES or custom filmic tone mapping curves
- Games like God of War, Horizon Forbidden West, and Cyberpunk 2077 implement sophisticated HDR tone mapping with user-adjustable settings
- Console HDR calibration screens (PS5, Xbox Series X) help set correct tone mapping parameters for your specific display
Auto-exposure and tone mapping
In games, tone mapping often works alongside auto-exposure systems that simulate the eye's adaptation to changing light. Walking from a dark cave into bright sunlight triggers both auto-exposure adjustment and tone curve adaptation.
Gaming tip: Choose one supported tone-mapping mode before calibration and keep it consistent. Where a supported HGiG workflow lets the game handle the calibrated HDR range, avoid adding an aggressive display-side mapping pass that changes the intended result.
Tone Mapping in Photography
In photography, tone mapping refers to the process of converting HDR images (created by merging multiple exposure brackets) into a displayable format.
Photography workflow:
- Capture bracketed exposures (underexposed, normal, overexposed)
- Merge exposures into a 32-bit HDR image
- Apply tone mapping to compress the dynamic range for display or print
- Fine-tune the result with local adjustments
Software options:
Photomatix Pro and Luminar provide current options for photographic HDR processing, with presets and manual controls for adjusting the result. Aurora HDR no longer receives updates or upgrades and has been replaced by Luminar. The screenshot below illustrates a preset-based HDR workflow in HDRinstant.
Photography tip: Shoot in RAW format to capture the maximum tonal information. RAW files preserve 12-14 bits of data per channel compared to JPEG's 8 bits, giving tone mapping algorithms significantly more data to work with.
Tone Mapping in Video Editing
Video editors encounter tone mapping when working with HDR footage or converting between HDR and SDR deliverables.
HDR-to-SDR tone mapping compresses a wider HDR luminance range into an SDR range. Inverse tone mapping expands SDR luminance into an HDR output range; UniFab HDR Upconverter AI serves the SDR-to-HDR10 direction.
Common scenarios:
- Preparing HDR footage for an SDR social media or broadcast deliverable
- Expanding an SDR source for an HDR output through inverse tone mapping
- Matching footage shot in different HDR formats (HLG, PQ, HDR10)
Software support:
- FFmpeg: Configurable filters for HDR-to-SDR tone mapping workflows
- DaVinci Resolve: Advanced color management with customizable tone mapping curves in the HDR palette
- Final Cut Pro: Automatic tone mapping when working with mixed HDR/SDR timelines
For an HDR-to-SDR delivery, confirm the intended SDR target, inspect the exported file, and check that playback preserves expected color rather than relying on the timeline preview alone.
SDR-to-HDR10 Conversion with UniFab HDR Upconverter AI
Display-side tone mapping adapts playback to a screen, while inverse tone mapping changes the source file by expanding SDR luminance into an HDR output range. Older movies, classic TV shows, and personal videos recorded in SDR can be converted into HDR deliverables for compatible displays.
If you only need a brighter viewing experience, a light display-setting adjustment may be enough. If you need a reusable HDR file, UniFab HDR Upconverter AI performs local SDR-to-HDR10 conversion and provides HDR10 and Dolby Vision output options.
Why Convert SDR Video to HDR
- Expand the output luminance range: Inverse tone mapping analyzes SDR frames and expands brightness and contrast for an HDR output.
- Create an HDR deliverable: Conversion produces a separate file for playback on compatible HDR displays instead of changing only the current display settings.
- Check the result before a batch: Export a short clip and review highlight detail, color, playback, and file size before processing additional videos.
Local Processing and HDR Export Options
UniFab HDR Upconverter AI supports GPU-accelerated SDR-to-HDR10 conversion on Windows and Mac, with MP4 and MKV output and a maximum output resolution of 4K. A lifetime license is available for ongoing conversion needs.
- HDR output options: Export for HDR10 or Dolby Vision display workflows.
- Local batch handling: Process multiple authorized videos locally without uploading the source files.
Step-by-Step: How to Upgrade SDR to HDR Using UniFab
UniFab HDR Upconverter AI
- Convert SDR videos to HDR10/Dolby Vision
- 30-day free trial for full features without watermark
UniFab HDR Upconverter AI
UniFab HDR Upconverter AI
- Convert SDR videos to HDR10/Dolby Vision
- 30-day free trial for full features without watermark
HDR Upconverter AI for Mac
Step 1: Choose HDR Upconverter and import your video
Download UniFab from the official website, launch the application, and select the HDR Upconverter module. Import an SDR video that you own or are authorized to process.
Step 2: Customize the output settings
Choose an HDR10 or Dolby Vision output option, select MP4 or MKV, and set the output resolution up to 4K.
Step 3: Start the conversion
Click the Start button to export a short clip first. Check highlight detail, color, playback, and file size on the intended display, then use the same settings for the remaining files or a batch.
Common Tone Mapping Issues and Fixes
Even with advanced tone mapping technology, problems can occur. Here are the most common issues and how to resolve them:
Washed out HDR content:
- Confirm that the player or device is receiving an actual HDR signal and using the intended HDR picture mode.
- Check that the source, output color handling, and target display are using compatible HDR settings.
- Identify whether the file is playing directly in the client or being transcoded by a server. For direct playback, check the source in an HDR video player with compatible color handling; for transcoding, adjust the server component that performs tone mapping.
Overly dark HDR image:
- A darker image is not necessarily a fault: on supported LG TVs, HGiG can look darker than Dynamic Tone Mapping On.
- Ensure the room lighting is appropriate (very bright rooms can make HDR look dark)
- Check that the content is actually HDR (some streaming services downgrade quality based on bandwidth)
Halo artifacts around bright objects:
- This is typically caused by aggressive local tone mapping
- Reduce the "local contrast" or "tone mapping intensity" setting
- Switch to a more conservative tone mapping preset
Color banding in gradients:
- Usually caused by insufficient bit depth in the signal chain
- Ensure 10-bit or 12-bit color output is enabled
- Use higher bitrate streaming settings or physical media
Inconsistent brightness between scenes:
- Check whether the brightness change is present in the source, the player output, or the display processing before changing tone-mapping settings.
- Update your TV firmware (manufacturers regularly improve tone mapping algorithms)
Conclusion
Tone mapping adapts HDR content to the luminance range and processing behavior of a target display. Understanding the difference between static and dynamic approaches, and between global and local algorithms, helps you make informed decisions about your viewing and content creation setup.
For HDR viewing, match the tone-mapping mode to your display and use case. If you have SDR content intended for HDR output, or footage that is simply too dark, learn how to brighten a video first, then compare the best HDR software options for that workflow.
FAQs about HDR Tone Mapping
What is the difference between HDR and tone mapping?
HDR (High Dynamic Range) refers to content that captures or contains a wider range of brightness values than standard content. Tone mapping is the processing technique that adapts that HDR content for display on screens with limited brightness. HDR-to-SDR tone mapping compresses the luminance range for an SDR target, while inverse tone mapping expands SDR luminance into an HDR output range.
Should I turn on tone mapping on my TV?
There is no universal on-or-off answer. On supported LG TVs, Dynamic Tone Mapping On can suit a brighter presentation, while HGiG can suit compatible HDR games that prioritize consistency. Off and HGiG remain separate choices.
How do I configure tone mapping on my TV or monitor?
Open the model-specific HDR picture controls while an HDR source is active. On supported LG TVs, HGiG may require a compatible HDR input and Game Optimizer mode. Other brands may use labels such as Static or Active, so follow the options provided for that display rather than treating them as LG equivalents.
What is inverse tone mapping?
Inverse tone mapping expands SDR luminance into an HDR output range, while HDR-to-SDR tone mapping compresses a wider HDR range for an SDR display or deliverable. It can create an HDR version from SDR footage, but it does not restore the source's original HDR information.
What is the best software for HDR tone mapping?
There is no universal best option. Photomatix Pro and Luminar support photographic HDR workflows, while Final Cut Pro and DaVinci Resolve handle HDR and SDR video timelines. FFmpeg offers configurable filters for technical HDR-to-SDR workflows. Choose software based on whether you need photo processing, HDR-to-SDR delivery, or inverse SDR-to-HDR conversion. UniFab HDR Upconverter AI serves the inverse SDR-to-HDR10 workflow.