How to Convert Multiple FITS Images to JXL?
1. Download and Install reaConverter
reaConverter is a standalone Windows app — download, install, and start converting FITS files in under two minutes. Built-in editing tools let you resize, crop, or watermark as you convert.
2. Load your FITS files
Launch reaConverter and load the FITS files you want to convert. Add a few files or thousands, batch processing handles them all.
Drag-and-drop FITSs directly into reaConverter or use the folder browser to load entire directories.
3. Select JXL as output format
Set JXL as output format and select where to save your converted files. Customize quality settings if needed.
4. Start FITS to JXL conversion
Press Convert to begin processing. You can watch the progress or minimize and let it run in the background.
Your converted JXL files will appear in the destination folder as soon as processing completes.
Before you convert FITS to JXL
FITS stores 32-bit greyscale covering the full dynamic range of the scan, and JXL shows 8 bits. The conversion applies a window level, so what ends up visible depends on the window you choose. Decide separately whether patient metadata should be copied to the output or stripped from it. FITS stores pixels without compression loss and JXL does not, so this is a one-way step. Choose a high quality setting, and avoid converting the same file back and forth, because each pass compounds the artefacts.
