Ultra HDR Viewer
Analyze an Ultra HDR image, preview its SDR base, and use native HDR rendering when the browser and display support it.
Private by default
Gain-map and JPEG analysis happens locally; the photo is not sent to a conversion service.
About this ultra hdr viewer
Ultra HDR uses a normal SDR JPEG plus gain-map data that compatible renderers apply on HDR displays. This viewer reports detected gain-map/container evidence, shows the authored SDR fallback, and also lets the browser render the original file when it supports the format.
A bright-looking preview alone does not prove HDR output. The analysis separates file capability from display capability and marks malformed or incomplete gain-map structures rather than treating any HDR-related XMP string as valid.
Analysis and display are reported separately. Structural checks can confirm a gain-map relationship regardless of the monitor, while an original-image preview is handed to the browser's color pipeline. The authored SDR base is also shown as a deterministic fallback, giving a useful result even when there is no reliable API that proves the display is emitting HDR luminance.
How it works
- 1Choose a compatible file or paste an image from the clipboard.
- 2Review the detected format and options, then start the local processing job.
- 3Check the result details and download the new file, extracted data, or generated package.
Example use cases
- Handle ultra hdr viewer without creating an account or installing desktop software.
- Inspect or prepare JPG, JPEG files before sharing them with another person or service.
- Keep private file contents out of a remote conversion queue.
Supported formats and limits
- Accepted input
- JPG, JPEG
- Maximum file size
- 100 MB per file
- Batch processing
- One file at a time
- Processing location
- On this device
Limitations
- True HDR output depends on the full browser, operating-system, color-management, and display chain.
- The viewer does not claim HDR is active merely because the original preview looks brighter.
- Supported structural analysis focuses on Ultra HDR JPEG; other gain-map containers require separate validation.
Why use this tool
- The real tool appears before supporting content, so the task starts immediately.
- Heavy code is loaded only for this utility and work is moved off the main interface where practical.
- Results use the bytes actually produced or detected—never a predicted size or fake success state.
Frequently asked questions
Is my file uploaded to a server?
Gain-map and JPEG analysis happens locally; the photo is not sent to a conversion service.
Can this viewer prove my screen is showing true HDR?
It can verify file capability and use native rendering when available, but web APIs do not provide a universal proof of the final luminance emitted by every display pipeline.
What is the SDR base preview?
It is the normal JPEG image authored for non-HDR readers. Compatible Ultra HDR software combines that base with the gain map for expanded output.
Why was my file rejected even though the extension looks correct?
The contents may be empty, corrupt, too large, or a different format that was renamed. Re-export the original file from its source app and try again.
Does this work on phones?
Yes in current Chrome, Safari, Edge, and Firefox where the required browser or WebAssembly feature is available. Large jobs may complete more reliably on a device with more memory.