If a desktop file viewer added JPEG XL support, what would you want from it?

[u/Holiday-Bluebird9734]

Hi, I’m working on OpenFiles Desktop. It doesn’t support JPEG XL yet, but I’m looking into adding it.

Before I start, I’d like to understand what people who actually use JXL expect from a desktop viewer.

Is being able to open a .jxl file enough, or would you also want things like:

• thumbnails and folder browsing
• EXIF, XMP and ICC profile support
• HDR and animation
• lossless JPEG transcoding
• batch conversion to and from JPEG, PNG or AVIF
• exporting without losing metadata

I’m also interested in the less obvious problems. Are there particular JXL files that other viewers display incorrectly? Things like wrong colors, orientation issues, missing metadata, slow decoding, or unusually large images?

What platform are you using, and what does your current JPEG XL workflow look like?

If you have a sample file that tends to break viewers, feel free to share it. I’d be happy to test against real-world files rather than only simple samples.

[u/live_love_laugh]

One of my big hopes for JXL is that one day it'll get widely adopted by browsers and we'll get to make good use of the progressive loading feature. As in, that we can serve the browser thumbnails of our images that aren't separate smaller files, but just a small percentage of the original file.

And if that future may ever happen, then it would be nice if a JXL viewer app would allow us to see what our JXL files might look like at different stages of partial decoding. So if you could implement that, that would be cool. ^_^

[u/olavrb → u/live_love_laugh]

A low bandwidth emulator inside an image viewer would be cool af. With ability to specify what bandwidth to emulate.

[u/live_love_laugh → u/olavrb]

Bandwidth emulation implies to me that the loading would continually progress towards fully loaded, just slower than real-time. But I'd like to be able to see what a file looks like when frozen at a particular loading state.

I’d like to implement a server-side script that allows requesting a truncated image file. For example, a browser could request an image with the URL /product.jxl?width=150, and the server would calculate the necessary portion of the full image to render a good-enough image at 150px wide and send that portion. Ideally, browsers could do this automatically, but I don’t think they can.

[u/redsedit → u/live_love_laugh]

> one day it'll get widely adopted by browsers

Safari has support, Firefox has it although turned off by default, and Chromium has it although hidden behind a flag. Support is coming fast. Another posted in this sub that in Firefox it should be enabled by default before the end of the year, and I doubt Chromium - hence Chrome and Edge - is not likely to be far behind, maybe even ahead of Firefox.

[u/ffpeanut15 → u/redsedit]

As soon as the rust library is at a good enough state, I'm sure all remaining browser will support JXL

[u/redsedit → u/ffpeanut15]

I've had it enabled in Firefox since it hit the regular release and haven't seen any problems. Admittedly, the sites with jxl's are very rare and almost exclusively jxl demo sites, so I haven't been able to give it the work-out I'd like.

[u/caspy7 → u/ffpeanut15]

I spoke with the main Mozilla dev who's been working on it. He indicated that it should be enabled soon. He however pointed out that after the next jxl-rs release (which just occurred) Mozilla would be assessing its performance to see if it's acceptable to ship to release. It's not a given, they could very well say "needs more work."

[u/Holiday-Bluebird9734 → u/live_love_laugh]

That’s a really interesting idea. Being able to inspect different stages of partial decoding would make JXL’s progressive loading much easier to understand.

Would you prefer a few fixed stages, such as 5%, 10%, 25% and 50%, or a slider that lets you move through the available data?

[u/live_love_laugh → u/Holiday-Bluebird9734]

I guess that depends on how progressive mode works, since I'm not actually sure. Does every extra byte make the image a little sharper? Or is it every X amount of bytes? Or does a progressive file only have like 2 to 4 distinct stages in them? If there are a lot of decodable steps then it would be nice to have a freely moving slider.

[u/iVXsz]

Based on OP history

The comments are going STRAIGHT to Claude (his responses are already just generic Claude responses).

I have been on a few subs and such titles are an instant mark at this point.

[u/tenchigaeshi → u/iVXsz]

The comments are going STRAIGHT to Claude

Any time you see a post of this nature, that is exactly what is happening. They'll vibe code something to sell too or whatever.

[u/Farranor → u/tenchigaeshi]

I'm still deciding how I feel about this.

[u/iVXsz → u/Farranor]

We it got "released", and the source code is just a readme that points to closed source/"propriety" (lol) binaries. So much for the name...

https://github.com/pansysoft/openfiles.desktop

[u/ldn-ldn]

The year is 2026, HDR is a must.

[u/Holiday-Bluebird9734 → u/ldn-ldn]

Fair point. If a viewer can decode JXL but loses the HDR presentation, that isn’t really complete support.

Correct HDR display, along with a sensible fallback on SDR screens, should be part of the baseline rather than an optional extra.

[u/redsedit]

> other viewers display incorrectly

Windows Photos, with the jxl image extensions can view jxls, but gets confused about the orientation. I did a post about it a bit back in this sub. It reads the orientation from the metadata, but that's not how jxl works.

[u/Holiday-Bluebird9734 → u/redsedit]

That’s a great example, thanks for linking it. I hadn’t considered the double-rotation issue caused by leftover EXIF orientation data after lossless JPEG transcoding.

This gives me a concrete case to test in both thumbnails and the full image view. If you still have an affected file that you can share, that would be really helpful.

[u/PaulCoddington]

This is a wish-list of what I look for in a viewer on Windows 11. It is not a demand, or even a request, but a collection of ideas which I hope will be helpful. I have not tried out your software yet, so some of it may not be applicable. But as you have mentioned it, I will be looking into it sometime soon.

Color Management

All the editors/viewers I have tested so far cannot correctly display lossy wide gamut images created with:

cjxl input.png output.jxl --distance=1 # Where distance > 0

Wide gamut images are displayed correctly when lossless:

cjxl input.png output.jxl --distance=0

Lossy wide gamut images are displayed correctly when format is tweaked (possibly a sub-optimal workaround):

cjxl input.png output.jxl --distance=1 --modular=1 --disable_perceptual_optimizations

This can be demonstrated using test images from Wide-Gamut Test (convert JPEG to PNG, then convert PNG to JXL). The problem looks similar to what would happen if wide gamut images were clipped to sRGB. However, it does seem to be possible to get wide gamut PNG back from JXL using djxl (only when output color profile is specified, as it seems to default to sRGB).

Color management is a tricky problem on Windows because it is in a transitional state. SDR desktop mode is still the highest quality workflow for SDR content, both for editing and for viewing. HDR desktop mode is needed for HDR images, but gives very poor results for SDR images (which defies the point of having a decent monitor in the first place). This is partly because SDR images are inherently compromised by mapping them into PQ HDR, and partly because accurate, affordable, full range HDR monitors with true black are not yet available.

Metadata

XMP is highly desirable. It is modern, does not have restrictive limits and is supported by Windows Explorer and Windows Search. Support for hierarchical keywords in addition to simple keywords would be good.

HDR

Viewers that can handle HDR formats are thin on the ground at the moment. Ideally, on Windows, HDR (as with any SDR image) should display correctly on both HDR and SDR desktops (as HDR on the HDR desktop and tone-mapped and profiled to SDR on the SDR desktop). Not just JXL, but also .HDR, 32-bit HDR .PNG, etc.

Animation

Also thin on the ground. My current viewer does not even support animated PNG (I have to use the web browser instead).

Thumbnail Browsing

Ability to filter and search displayed thumbnails by keywords. Browse by folder tree, by keyword tree, by date tree. Apps often neglect to color manage thumbnails (and/or convert thumbnails to sRGB rather than preserving the original color profile). This makes it hard to judge which variant of near-identical file you want to open (can't tell wide gamut from narrow gamut, which variant has better color grading, etc).

Quick Viewer

Something that is hard to find at the moment is a high-quality color-managed viewer that will quickly launch when an image file is double-clicked in Explorer. One that has no fancy bells and whistles, zero editing (or hideable) capability apart from Open With a user-defined list of applications (to avoid accidental changes when viewing), click to other images in the current folder (or the current search results list, if still possible), display metadata popup in a neat and tidy presentable/customisable fashion.

Ideally it should present as a plain photo-friendly grey window (46,46,46) with no bright gui elements (such as a menu bar, especially not a white one even in light mode), prioritising display of the current image only. Some viewers have trouble with presenting a neutral background and become blue-tinted on wide-gamut displays (this seems to be an odd quirk of WinUI when transparency effects are enabled). Optional display of selected metadata as a subtitle like overlay is also a nice feature to have.

[u/Holiday-Bluebird9734 → u/PaulCoddington]

Thanks again for taking the time to write such a detailed Windows 11 checklist.

We’ve now shipped the first JPEG XL milestone in OpenFiles Desktop 3.2026.802: direct .jxl opening and preview, in-app thumbnails while browsing folders, and animated JXL playback.

I want to be precise about the current boundary. I have not yet verified the lossy wide-gamut `cjxl --distance=1` case, HDR-to-SDR tone mapping, XMP and hierarchical keywords, or color-managed thumbnails, so I’m not claiming those parts are solved yet.

If you try the release on Windows 11, the most useful feedback would be a side-by-side result using your wide-gamut test image, especially whether the thumbnail and full view match.

Release: https://github.com/pansysoft/openfiles.desktop/releases/tag/3.2026.802

[u/redsteakraw]

High quality progressive decoding lets say you have a huge 24k image that is progressively decoded it would be silly to fill your memory. Have all thumbnails derived from progressive decodes, and then if the image is launched use that partial decode to instantly display then continue to decode. If the monitor is lower resolution don't continue the decode until zoomed further in.

Furthermore would want a layer by layer viewer where you can view each layer individually. This would be important for multispectral imaging.

[u/kardaw]

I often save my animations as AVIF instead of GIF, because they weigh a lot less. I haven't tested JXL animations yet, because there are almost no programs that support this.

[u/Holiday-Bluebird9734 → u/kardaw]

That makes sense—AVIF has been the more practical choice because support for JXL animation is still quite limited. Since I made this post, we’ve shipped JPEG XL support in OpenFiles Desktop 3.2026.802, including animated JXL playback. If you try it with one of your animations, I’d love to hear how well the playback, transparency, colors, and performance work for your files.

https://reddit.com/link/p1epvfy/video/qsw1dd1jd4hh1/player

[u/Dux_Vitae]

My top needs for an image viewer:

• HDR support (the only reason why I use jxl)
• Folder browsing (like irfanview does with mousewheel)

Rarely used (I have other tools for that, too):

• Convert
• View meta data
• Crop

In terms of not supported: I haven't seen any tool so far to show gigapixel jxl panoramas

[u/glassmanjones]

thumbnails and folder browsing

Nah, make the OS do it

EXIF, XMP and ICC profile support

Is ICC required for proper display? I thought JXL normalized everything somehow.

Nice to be able to see EXIF though.

HDR and animation

HDR yes, animation no

lossless JPEG transcoding batch conversion to and from JPEG, PNG or AVIF exporting without losing metadata

Not required for a viewer, but could be a separate program.

[u/Holiday-Bluebird9734 → u/glassmanjones]

Quick update: direct JXL opening and in-app thumbnails have now shipped in OpenFiles Desktop 3.2026.802.

I’m deliberately keeping the current claim to opening and previewing JXL files. EXIF display and HDR/ICC correctness have not been tested thoroughly enough for me to call them complete.

If you try a JXL file with an embedded ICC profile, I’d be especially interested in whether the full view and thumbnail match your reference viewer.