Try it
Drop a photo. Get a gain map image. Everything runs in your browser.
Drop a photo
JPEG · PNG · WebP · AVIF · HEIC · SVG
The same file, two renderers
Standard clamps highlights to SDR white. Ultra unlocks the gain map layer, the same bytes parsed differently by the display pipeline.
Standard
Ultra
Standard
Ultra
100 brand logos
100 photographs
What is a gain map image?
HDR is an expanded brightness range: image highlights can sit above the SDR ceiling. A gain map image encodes a normal SDR image plus a secondary brightness map. Unsupported apps render the SDR layer and ignore the rest.
EDR is Apple's term for displaying brightness above SDR reference white. HDR describes the image content. They are not the same word and are often misused interchangeably.
The cross-platform technical name is HDR gain map image. Consumer brands include Adaptive HDR (Apple) and Ultra HDR (Android/Google). This site encodes those files locally in the browser. No upload, no server.
Blacks do not necessarily get blacker. EDR lifts highlights, not the shadow floor.
Every platform named it differently
Vendors, platforms, and standards each coined their own acronym.
| Name | Full form | Platform | What it means |
|---|---|---|---|
| EDR | Extended Dynamic Range | Apple | Apple's system for displaying brightness above normal SDR white |
| XDR | Extreme Dynamic Range | Apple | Apple branding for displays with high HDR brightness and contrast |
| Adaptive HDR | Adaptive High Dynamic Range | Apple | Gain map image system that supports both SDR and HDR display |
| Ultra HDR | Ultra High Dynamic Range | Google and Android | Gain map JPEG format and the closest Android equivalent to an EDR JPEG |
| Super HDR | Super High Dynamic Range | Samsung | Samsung branding for HDR photo capture and display |
| ProXDR | Pro Extreme Dynamic Range | OPPO and OnePlus | Branding for HDR photo capture and display |
| Pro HDR | Pro High Dynamic Range | Xiaomi | Branding for brighter HDR photo display |
| Advanced Color | Advanced Color | Microsoft Windows | Windows system covering HDR, wide color gamut, and higher color precision |
| HDR | High Dynamic Range | Industry standard | Content with a wider brightness range than SDR |
| SDR | Standard Dynamic Range | Industry standard | Traditional display brightness range |
| WCG | Wide Color Gamut | Industry standard | A broader range of reproducible colors |
| HDR10 | High Dynamic Range, 10 bit | Industry standard | Static metadata HDR format using 10 bit color |
| HDR10+ | High Dynamic Range, 10 bit Plus | Samsung and others | Dynamic metadata HDR format |
| HLG | Hybrid Log Gamma | BBC and NHK | HDR format commonly used for broadcast television |
| PQ | Perceptual Quantizer | SMPTE | HDR brightness transfer function used by HDR10 and Dolby Vision |
| DV | Dolby Vision | Dolby | Dynamic metadata HDR format |
| DisplayHDR | VESA Certified DisplayHDR | VESA | Display performance certification rather than an image format |
| HDR gain map | High Dynamic Range gain map | Cross platform | General technical term for an image containing SDR data plus additional HDR brightness information |
From the terminal
Batch-encode gain map images without a browser.
brew install gainmapUpvote on Product Hunt
Upvotes help designers and photographers find it.
View on Product Hunt →