=== PHP Runtime Environment ===
PHP_SAPI: litespeed
HOME:     
PATH:     /usr/local/bin:/usr/bin:/bin


$ which convert
/usr/bin/convert
[exit=0]

$ convert -version | head -n 1
Version: ImageMagick 6.9.13-25 Q16 x86_64 18639 https://legacy.imagemagick.org
[exit=0]

$ which cwebp
which: no cwebp in (/usr/local/bin:/usr/bin:/bin)
[exit=1]

$ cwebp -version
sh: cwebp: command not found
[exit=127]

$ which gif2webp
which: no gif2webp in (/usr/local/bin:/usr/bin:/bin)
[exit=1]

$ gif2webp -version
sh: gif2webp: command not found
[exit=127]

$ which optipng
which: no optipng in (/usr/local/bin:/usr/bin:/bin)
[exit=1]

$ optipng -v | head -n 1

[exit=0]

$ which jpegoptim
which: no jpegoptim in (/usr/local/bin:/usr/bin:/bin)
[exit=1]

$ jpegoptim --version
sh: jpegoptim: command not found
[exit=127]

$ which jpegtran
which: no jpegtran in (/usr/local/bin:/usr/bin:/bin)
[exit=1]

$ jpegtran -version
sh: jpegtran: command not found
[exit=127]

$ which pngquant
which: no pngquant in (/usr/local/bin:/usr/bin:/bin)
[exit=1]

$ pngquant --version | head -n 1

[exit=0]