stream: 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/stream - from package: ImageMagick

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

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