metapixel: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

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/metapixel - from package: metapixel

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