Can I get back the HDR brightness after converting to JPG?

No. Once the image is converted to 8-bit JPG, the extra brightness information is lost. You would need the original HDR AVIF file to recover the full dynamic range.

Why does my HDR AVIF look washed out on a normal monitor?

The monitor likely does not support the HDR transfer function (PQ or HLG) or the wide colour gamut. The image is being displayed without the correct brightness mapping, so it appears flat.

Does converting to PNG with 10-bit preserve HDR?

PNG supports 10-bit and 12-bit channels, but it does not support HDR transfer functions like PQ or HLG. The pixel values would be stored, but the display would not know how to map them to HDR brightness. The result may still look incorrect.

Is there a way to reduce banding when converting a 10-bit AVIF to 8-bit JPG?

Some converters apply dithering, which adds a small amount of noise to break up visible bands. This can smooth the gradient, though it may introduce a slightly grainy texture.

AVIF HDR and 10-Bit Colour Explained

AVIF supports high bit depth and HDR metadata, which is why avif hdr files can store far more luminance and colour information than standard JPEGs. Convert an HDR AVIF to an 8-bit format like JPG and the extra data must be compressed, so bright highlights look duller or clip. The fix is knowing what the format stores and what gets lost in conversion.

What Bit Depth Means in AVIF

Bit depth determines how many discrete levels each colour channel can hold. AVIF supports 8, 10 and 12 bits per channel. An 8-bit channel has 256 levels, a 10-bit channel has 1,024, and a 12-bit channel has 4,096. More levels mean smoother gradations and less risk of banding in skies or gradients. Standard JPEG is limited to 8 bits per channel, so it cannot match the subtlety of a 10-bit or 12-bit AVIF.

Why 10-Bit Matters for HDR

HDR content relies on a wide range of luminance values. With only 256 levels per channel, an 8-bit image cannot represent very dark shadows and very bright highlights without visible jumps between steps. A 10-bit image provides 1,024 levels, enough to encode the extended dynamic range smoothly. This is why avif 10 bit files are the standard choice for HDR photography and video frames.

HDR Transfer Functions PQ and HLG

AVIF can signal HDR transfer functions that define how luminance values are mapped to light output. Two common ones are PQ (SMPTE ST 2084) and HLG. PQ uses a perceptual curve that allocates more steps to darker tones, matching human vision. HLG is designed for broadcast and works with both HDR and standard displays. When an AVIF file contains one of these transfer functions, a compatible viewer knows to display the image with the correct luminance curve.

Without the proper transfer function, an HDR image may look washed out or too dark on a standard screen. Check that your browser supports the metadata before publishing hdr images web content, or the result will not match what you edited.

Wide Colour Gamuts in AVIF

AVIF can use wide colour gamuts such as BT.2020 and Display P3. These gamuts cover a larger range of colours than the sRGB gamut used by most standard JPEGs. BT.2020 is the widest, used in ultra-high-definition video, while Display P3 is common in modern monitors and mobile devices. An AVIF file with avif wide color gamut can display more saturated reds, greens, and blues than a typical JPG.

What Happens on Conversion

Convert such an AVIF to JPG and the colours must be squeezed into the smaller sRGB gamut. Expect the result to look less vivid, especially in areas with highly saturated tones.

Why HDR AVIFs Look Different When Converted to 8-Bit JPG

Converting an HDR AVIF to JPG involves two changes: reducing the bit depth from 10 or 12 bits to 8 bits, and tone mapping the HDR luminance range to standard dynamic range. Both steps alter the appearance.

Tone mapping compresses the wide luminance range into the narrower range of a standard JPG. Bright highlights that were bright in the HDR file get dimmed to fit. They look duller than the original AVIF.
Bit depth reduction cuts the number of levels per channel from 1,024 or 4,096 to 256. Smooth gradients develop visible bands, especially in areas of subtle luminance change.
Colour gamut mapping shrinks the wide colour gamut to sRGB, which reduces saturation in some hues.

If you see an avif to jpg hdr looks dull result, the tone mapping algorithm chose how to compress the highlights. Some algorithms preserve more detail in bright areas but make the whole image darker. Others brighten the midtones but let highlights clip to white.

How Tone Mapping Works in Practice

When you convert an HDR AVIF to JPG, the software applies a tone mapping curve. There is no single correct curve; different tools use different methods. Pick the method that suits the image, not the default.

Linear mapping scales luminance down uniformly. This makes the image look flat and dark.
Adaptive mapping compresses highlights more than midtones, preserving detail in bright areas while keeping normal luminance levels.
Clipping cuts off values above a certain luminance. Highlights become pure white, losing all detail.

For a natural look, choose adaptive mapping. Reserve clipping for images where highlights are not the subject.

Practical Tips for Working with HDR AVIF Files

When you need to share an HDR AVIF as a JPG, do these things:

Use a converter that lets you adjust tone mapping settings, if available.
Preview the result before finalising, because the appearance varies greatly between tone mapping algorithms.
If the original AVIF uses a wide colour gamut, expect some colour shift in the JPG.
For web display, keep the AVIF file for HDR-capable viewers and provide a separate JPG for older browsers.

Tools like those on avif.tools handle the conversion, but the quality of the output depends on the tone mapping method applied.