saoimage: 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 CentOS possible default full paths are:

/usr/bin/saoimage - from package: saoimage

You may install the required package with command yum install {package}

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