YUV444toRGB: 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/YUV444toRGB - from package: dirac

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

Error in other languages:
YUV444toRGB: bevel nie gevind nie
YUV444toRGB: comandă negăsită
YUV444toRGB: comando não encontrado
YUV444toRGB: commande introuvable
YUV444toRGB: command not found
YUV444toRGB: käsku ei ole
YUV444toRGB: không tìm thấy lệnh
YUV444toRGB: komanda nerasta
YUV444toRGB: Kommando nicht gefunden.
YUV444toRGB: kommandot finns inte
YUV444toRGB: komut yok
YUV444toRGB: nie znaleziono polecenia
YUV444toRGB: níor aimsíodh an t-ordú
YUV444toRGB: no se encontró la orden
YUV444toRGB: no s'ha trobat l'ordre
YUV444toRGB: opdracht niet gevonden
YUV444toRGB: parancs nem található
YUV444toRGB: perintah tidak ditemukan
YUV444toRGB: príkaz nenájdený
YUV444toRGB: příkaz nenalezen
YUV444toRGB: команда не найдена
YUV444toRGB: командата не е открита
YUV444toRGB: 命令找不到
YUV444toRGB: コマンドが見つかりません