vips: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/vips - from package: libvips-tools

You may install the required package with command apt-get install {package}

Error in other languages:
vips: bevel nie gevind nie
vips: comandă negăsită
vips: comando não encontrado
vips: commande introuvable
vips: command not found
vips: käsku ei ole
vips: không tìm thấy lệnh
vips: komanda nerasta
vips: Kommando nicht gefunden.
vips: kommandot finns inte
vips: komut yok
vips: nie znaleziono polecenia
vips: níor aimsíodh an t-ordú
vips: no se encontró la orden
vips: no s'ha trobat l'ordre
vips: opdracht niet gevonden
vips: parancs nem található
vips: perintah tidak ditemukan
vips: príkaz nenájdený
vips: příkaz nenalezen
vips: команда не найдена
vips: командата не е открита
vips: 命令找不到
vips: コマンドが見つかりません