tgatoppm(1) on Linux
The text 40a678ab4cb3, as Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
convert TrueVision Targa file into a portable pixmap
Flags it lists
-
--alphaout -
--headerdump