hdmv_test: 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/hdmv_test - from package: libbluray

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

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