djxl

Decompress a JPEG XL image to another format

$ djxl [path/to/image.jxl] [path/to/output.ext]

$ djxl [[-h -v -v -v -v|--help --verbose --verbose --verbose --verbose]]

djxl [options] <input.jxl> [<output>]

-o, --output=FILE
    Set output filename (default: input basename with .png)

--export_png=BOOL
    Export as PNG (default: auto)

--export_ppm=BOOL
    Export as PPM

--export_pfm=BOOL
    Export as PFM (for HDR)

-f, --frame=INT
    Decode specific frame (default: 0)

--import_profile=ICC_FILE
    Apply ICC color profile

-q, --quality=FLOAT
    Lossy decode quality (0-1, default:1/lossless)

-d, --decodability=BOOL
    Check decodability only (no output)

--version
    Print version info

-h, --help
    Show full help

djxl is the reference decoder for JPEG XL (.jxl) images, part of the libjxl library from the Joint Photographic Experts Group. It converts JXL files to standard formats like PNG, PPM, or PFM.

JPEG XL offers superior compression, lossless transcoding from JPEG/AVIF/WebP, and modern features like animation, HDR, and wide gamut support. djxl supports decoding single frames, animations, and progressive images.

Install via package managers (e.g., apt install libjxl-tools on Debian/Ubuntu) or build from source. Output defaults to input basename with .png extension if unspecified. Ideal for batch processing or verifying JXL files.

Key strengths include lossless reconstruction and metadata preservation. Use with cjxl for encoding.

Requires libjxl installation; not in core Linux distros. Experimental format—browser support varies. Large files may need much RAM.

djxl input.jxl output.png
djxl -f 5 animation.jxl -o frame5.png

Developed by Alliance for Open Media (JPEG XL project) since 2018. libjxl v0.10+ stabilized djxl in 2023; royalty-free successor to JPEG.

cjxl(1), jpegtran(1), convert(1)