composite: 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/composite - from package: ImageMagick

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

On Debian possible default full paths are:

/usr/bin/composite - from package: graphicsmagick-imagemagick-compat

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

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