Guide
Private Ultra HDR Image Converter
Convert an opaque JPG, PNG, or WebP into a backward-compatible Ultra HDR JPEG, or turn an Ultra HDR JPEG back into a plain SDR image. Both directions are verified locally.
What does SDR to Ultra HDR create?
It keeps a normal SDR JPEG as the fallback, adds a smaller JPEG gain map, and includes the metadata and MPF index that compatible HDR viewers use to show brighter highlights.
Opens the free tool. Your selected files stay in this browser.
Clear answers
Create or remove an HDR gain map without uploading the image, then download only after the new JPEG passes local structural and image checks.
Convert an opaque JPG, PNG, or WebP into a backward-compatible Ultra HDR JPEG, or turn an Ultra HDR JPEG back into a plain SDR image. Both directions are verified locally.
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01
What does SDR to Ultra HDR create?
It keeps a normal SDR JPEG as the fallback, adds a smaller JPEG gain map, and includes the metadata and MPF index that compatible HDR viewers use to show brighter highlights.
Automatic SDR or Ultra HDR direction detection
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02
Can it convert Ultra HDR back to a normal JPG?
Yes. The converter uses the stored SDR base rendition, re-encodes it as a plain JPEG, and verifies that the result no longer declares a gain map.
Natural, Glow, and Graphic highlight profiles
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03
Will every screen show the HDR effect?
No. Readers without gain-map support display the ordinary SDR fallback. HDR appearance also depends on the display, operating system, viewer, brightness, and any later re-encoding.
Locally decoded and verified JPEG output
Real-life uses
Practical ways to use Private Ultra HDR Image Converter
These examples show where the tool can help and what still needs a deliberate human check before the result is used or shared.
Making an SDR image more expressive on HDR displays
Add controlled highlight headroom to a finished opaque still while retaining a backward-compatible SDR rendition.
Creating a plain SDR delivery copy
Remove the gain map when an editor, print service, or publishing system handles ordinary JPEG more predictably.
Testing an HDR publishing workflow
Compare Natural, Glow, and Graphic profiles before deciding whether the destination actually preserves Ultra HDR.
Worked example
Preparing a bright product image for mixed displays
The photo should look ordinary on SDR screens while selected highlights gain headroom on compatible HDR displays.
Before
The source has one SDR rendition
- Highlights are already present in the source
- The converter cannot recover detail that was never captured
After
The output carries two coordinated renditions
- Choose a restrained profile and create the Ultra HDR JPEG
- Check the base image and embedded gain-map structure locally
What you receive: a verified JPEG that remains viewable as SDR and can show enhanced highlights where Ultra HDR is supported.
Four local steps
Can it convert Ultra HDR back to a normal JPG?
- 01
Automatic SDR or Ultra HDR direction detection
Choose one opaque still JPG, PNG, WebP, or Ultra HDR JPEG.
- 02
Natural, Glow, and Graphic highlight profiles
For an SDR source, select Natural, Glow, or Graphic highlight response; Ultra HDR sources are automatically prepared for SDR output.
- 03
Locally decoded and verified JPEG output
Create the JPEG and wait while its container and embedded images are checked locally.
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Automatic SDR or Ultra HDR direction detection
Download the verified Ultra HDR or plain SDR JPEG.
Final check
Check the result before you use it
Verification belongs in the workflow. Review the downloaded result itself rather than relying only on the preview inside the tool.
- Review the result on both an ordinary SDR viewer and a compatible HDR display when possible.
- Check skin tones, logos, highlights, and gradients for unnatural clipping or glow.
- Confirm that later editing or sharing has not stripped the gain map.
Clear answers
Will every screen show the HDR effect?
No. Readers without gain-map support display the ordinary SDR fallback. HDR appearance also depends on the display, operating system, viewer, brightness, and any later re-encoding.
- SDR-to-HDR adds display headroom to existing highlights; it cannot recover uncaptured detail or replace a true HDR capture workflow.
- Transparent and animated inputs are not supported because the Ultra HDR base rendition is an opaque still JPEG.
- HDR rendering depends on the display, viewer, brightness settings, and whether later editing or sharing preserves the gain map.