camera-calib: 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/camera-calib - from package: mrpt-apps

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

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