.jxr File Extension

What kind of file is a .jxr?

A .jxr file is usually a JPEG XR still image. The format supports lossy and lossless compression, transparency, high dynamic range, wide-gamut color, and several integer, fixed-point, and floating-point sample formats.¹ It is technically related to Microsoft's earlier HD Photo format, but the standardized JPEG XR bitstream is not identical to every older HD Photo file.

Microsoft's Windows Imaging Component documentation uses the de facto media type image/jxr. That value is not registered separately by IANA. Poly classifies .jxr files with the related image/vnd.ms-photo MIME type, which IANA registered for HD Photo.²

Containerized files in this family commonly begin with 49 49 BC 01. Older pre-release HD Photo files can use 49 49 BC 00.³ Check the signature and decode the image rather than trusting the filename alone.

How do I open a .jxr on my computer?

On Windows, use an image application that reads through Windows Imaging Component. Windows includes a native JPEG XR codec with decoding and encoding support.⁴

macOS and Linux do not offer equally dependable built-in support. ImageMagick can read and write JXR when its optional jxrlib delegate is installed, so confirm support in the particular build you use.⁵ Current web browsers generally do not display JPEG XR directly, making conversion the practical choice for sharing.

Treat unexpected .jxr files as untrusted input. Open them with maintained software, and avoid obsolete codec plug-ins from unofficial download sites.

Poly support for .jxr

Poly stores, syncs, shares, versions, and finds .jxr files by name and basic file properties. It does not currently decode their pixels, generate a thumbnail, extract image metadata, create a visual-search representation, or make the picture available to the Poly agent.

Download the original and open it in a JPEG XR-compatible application when you need to inspect or convert the image.

History of .jxr

JPEG XR grew from Microsoft's Windows Media Photo technology, later renamed HD Photo. Microsoft submitted the technology for JPEG standardization in 2007. The core JPEG XR coding specification became ITU-T Recommendation T.832 in 2009 and ISO/IEC 29199-2.⁶

The .jxr suffix distinguishes the standardized format from the older .wdp convention. Microsoft says its Windows codec can decode both, while its encoder has produced JPEG XR-compliant output since Windows 8.⁴

Working with .jxr and alternatives

Choose a conversion target according to what the source contains:

• PNG for a broadly readable lossless copy with transparency.
• TIFF for high-bit-depth editing, color-managed interchange, or archival derivatives.
• JPEG for compact photographs when 8-bit output, lossy compression, and no alpha are acceptable.
• WebP or AVIF for modern web delivery.

JPEG XR may contain HDR values, wide-gamut color, alpha, and higher bit depths. A careless conversion can clip highlights, change colors, flatten transparency, or remove metadata. Keep the original .jxr, choose an explicit output color space and bit depth, and compare the result before relying on the converted copy.