Convert hdiff to flif Online: hdiff2flif

You can use Tom's Editor to easily convert images from
Horizontal difference image .HDIFF to Free Lossless Image Format .FLIF.
Tom's Editor is a free, online image manipulation and converter program.

Go to Tom's Editor

HDIFF

Horizontal difference image is an image format with extension HDIFF.

FLIF

Free Lossless Image Format is an image format with extension FLIF.