fib2image: 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/lib/cmtk/bin/fib2image - from package: cmtk

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

Error in other languages:
fib2image: bevel nie gevind nie
fib2image: comandă negăsită
fib2image: comando não encontrado
fib2image: commande introuvable
fib2image: command not found
fib2image: käsku ei ole
fib2image: không tìm thấy lệnh
fib2image: komanda nerasta
fib2image: Kommando nicht gefunden.
fib2image: kommandot finns inte
fib2image: komut yok
fib2image: nie znaleziono polecenia
fib2image: níor aimsíodh an t-ordú
fib2image: no se encontró la orden
fib2image: no s'ha trobat l'ordre
fib2image: opdracht niet gevonden
fib2image: parancs nem található
fib2image: perintah tidak ditemukan
fib2image: príkaz nenájdený
fib2image: příkaz nenalezen
fib2image: команда не найдена
fib2image: командата не е открита
fib2image: 命令找不到
fib2image: コマンドが見つかりません