HDR Screenshot Recovery

About HDR Screenshot Recovery

Take a screenshot on Windows with HDR turned on and it often comes out broken in one of two ways: the whole image looks as if a gray veil was laid over it, or the bright areas turn into flat white blobs. This tool reads the file, diagnoses which kind of damage it has, and applies a matching preset to produce an SDR image that looks right everywhere, plus an optional corrected HDR PNG.

How much comes back depends on what the file still contains. A .jxr from Xbox Game Bar, or an HDR PNG or AVIF, still holds real HDR values, so highlights can be recovered. An 8-bit PNG that was already clipped at 255 has lost that detail for good, and no tool can invent it back.

Why HDR desktops produce washed-out screenshots

With HDR on, Windows composes the desktop in scRGB, a linear floating-point space in which 1.0 corresponds to 80 nits and brighter highlights are stored as values above 1, such as 2.0 or 6.0. Ordinary SDR apps are placed inside that space according to the SDR content brightness slider in Settings.

Trouble starts when a capture path converts that buffer to 8-bit sRGB without proper tone mapping. Squeeze the whole range in linearly and blacks lift toward gray while saturation drains away: the washed-out look. Clip everything above 1.0 instead and the highlights blow out to white. Which symptom you get depends on the capture tool, the GPU driver and the Windows build, and the same complaint keeps reappearing on Microsoft's Q&A forums.

How the tool tells the damage apart

It first identifies the container from its magic bytes (JXR, PNG, JPEG, AVIF, WebP) rather than trusting the extension. A PNG with a cICP chunk is treated as HDR, and its PQ curve is decoded back to absolute luminance. Every input is converted to one internal form, linear Rec. 2020 with 1.0 meaning diffuse white, before analysis.

Four measurements drive the diagnosis: headroom (how many times brighter than diffuse white the brightest pixel is), the fraction of pixels with at least one clipped channel, the fraction with all three clipped, and mean saturation. Headroom above 1.05 means genuine HDR data and selects the tone-mapping preset. More than 2% fully white pixels, or more than 8% with a clipped channel, selects the blown-highlights preset. Washed-out is diagnosed only when mean saturation is below 0.16 and the blacks are lifted or the whites compressed. Low saturation is required because a perfectly normal photo full of dark furniture can also have lifted-looking blacks.

Tone mapping: folding a wide range into 0 to 1

HDR input is compressed with one of three curves: extended Reinhard, Hable's filmic curve (from Uncharted 2), or Narkowicz's ACES approximation. All of them leave shadows nearly untouched and give less and less output for each extra unit of input, reaching exactly 1.0 at the tone-map white point W. Presets set W to 0.9 times the measured headroom, clamped between 2.5 and 12.

The curve is applied to luminance only, not to each channel separately, and R, G and B are scaled down together by the same ratio. A very bright, saturated color such as a neon orange sign therefore keeps its hue instead of drifting toward yellow. If one channel still exceeds the display range after scaling, the pixel is scaled down as a whole, keeping hue and saturation at the cost of a little brightness. Highlight rolloff moves very bright areas toward white, so if highlight colors look washed out, lower the rolloff or raise the tone-map white.

Exporting an HDR PNG

The HDR output is a 16-bit PNG carrying a cICP chunk with the values 9, 16, 0, 1, meaning Rec. 2020 primaries, PQ transfer and full range. Display white (1.0) is placed at 203 nits, the reference white recommended in ITU-R BT.2408, and values are capped at the peak you choose (400 nits by default). Chrome and Edge display these files as HDR; viewers that ignore cICP show them as SDR or with wrong colors. For chat apps, social media or blogs, the SDR output is the safer choice.

Avoiding the problem next time

Win+Alt+PrtScn in Xbox Game Bar saves both a .jxr with the HDR data and a tone-mapped PNG, so you always have the raw version to fall back on. If you only need a document or web page captured, temporarily switching HDR off before capturing avoids the conversion entirely. For game screenshots, keep the .jxr: it is the only format here that lets highlights come back.

Worked examples

How to use it

1. Drop the screenshot file or paste it with Ctrl+V.
2. Check the diagnosis and suggested preset, and compare with the before/after slider.
3. Adjust exposure, saturation or black point if needed, then save as SDR or HDR PNG.

Frequently asked questions