Installation:

copy into new foler. e.g. C:\Program Files\XashTools\
run extragen.exe or ximage.exe
wait for a while
tools sucessfully installed.

extragen.exe usage:

copy extragen into game directory (for Quake it's ID1, for Quake2 it's baseq2, for Half-Life 2 it's hl2 etc)
run it without args or with -file <filename>

ximage.exe usage:

-rotate <90|180|270>			rotate image by specified angle
-flip <vertical|horizontal|diagonal>		flip image
-pow2					force image size to nearest power of two
-resample <width height>			resample to specified values
-pbr					prepare glossmap to pbr-format
-makeLuma					extract self-illuminated maps from Quake1 textures
-file					mask of input files
-to					extension of destination format (skip if don't want to change format)

supported formats:	tga, jpg, png, dds, pcx, bmp