extract_j2k_from_mj2: 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/extract_j2k_from_mj2 - from package: openjpeg

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

On Debian possible default full paths are:

/usr/bin/extract_j2k_from_mj2 - from package: openjpeg-tools

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

Error in other languages:
extract_j2k_from_mj2: bevel nie gevind nie
extract_j2k_from_mj2: comandă negăsită
extract_j2k_from_mj2: comando não encontrado
extract_j2k_from_mj2: commande introuvable
extract_j2k_from_mj2: command not found
extract_j2k_from_mj2: käsku ei ole
extract_j2k_from_mj2: không tìm thấy lệnh
extract_j2k_from_mj2: komanda nerasta
extract_j2k_from_mj2: Kommando nicht gefunden.
extract_j2k_from_mj2: kommandot finns inte
extract_j2k_from_mj2: komut yok
extract_j2k_from_mj2: nie znaleziono polecenia
extract_j2k_from_mj2: níor aimsíodh an t-ordú
extract_j2k_from_mj2: no se encontró la orden
extract_j2k_from_mj2: no s'ha trobat l'ordre
extract_j2k_from_mj2: opdracht niet gevonden
extract_j2k_from_mj2: parancs nem található
extract_j2k_from_mj2: perintah tidak ditemukan
extract_j2k_from_mj2: príkaz nenájdený
extract_j2k_from_mj2: příkaz nenalezen
extract_j2k_from_mj2: команда не найдена
extract_j2k_from_mj2: командата не е открита
extract_j2k_from_mj2: 命令找不到
extract_j2k_from_mj2: コマンドが見つかりません