dirac_decoder: 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/dirac_decoder - from package: dirac

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

On Debian possible default full paths are:

/usr/bin/dirac_decoder - from package: dirac

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

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