--- /dev/null
+galgen -- static images gallery generator
+
+That generator is written on zsh and is aimed only to deal with JPEG XL
+and WebP image formats solely. JPEG XL is superior to any other format
+both in lossy and lossless modes. The only exception is screenshots
+encoded in lossless WebP (VP8L) format.
+
+Just run that script inside the directory with .jxl/.webp files. For
+each file the small preview will be generated in lossy WebP format. Also
+corresponding HTML file is generated too, containing information about
+the picture and its metadata.
+
+If it is JPEG XL, then, for compatibility reason with non-bleeding edge
+software, alternative format is generated too: either JPEG (if JPEG XL
+contains losslessly transcoded JPEG), or PNG (leaving off the alpha channel).
+
+If image file has corresponding .txt, then it will be included as a
+preformatted text on HTML page.
+
+All images are sorted my modification date and grouped by pages,
+linking them together. If directory contains ".txt", then it will be
+included on the first page as a preformatted text.
+
+Following external utilities are called: djxl, jxlinfo, exiftool,
+pamtopng, pnmscale, pngcrush, advpng, webpinfo, dwebp, cwebp.