pgmtoy4m: 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
/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/pgmtoy4m - from package: mjpegtools

You may install the required package with command apt-get install {package}
Error in other languages:
pgmtoy4m: bevel nie gevind nie
pgmtoy4m: comandă negăsită
pgmtoy4m: comando não encontrado
pgmtoy4m: commande introuvable
pgmtoy4m: command not found
pgmtoy4m: käsku ei ole
pgmtoy4m: không tìm thấy lệnh
pgmtoy4m: komanda nerasta
pgmtoy4m: Kommando nicht gefunden.
pgmtoy4m: kommandot finns inte
pgmtoy4m: komut yok
pgmtoy4m: nie znaleziono polecenia
pgmtoy4m: níor aimsíodh an t-ordú
pgmtoy4m: no se encontró la orden
pgmtoy4m: no s'ha trobat l'ordre
pgmtoy4m: opdracht niet gevonden
pgmtoy4m: parancs nem található
pgmtoy4m: perintah tidak ditemukan
pgmtoy4m: príkaz nenájdený
pgmtoy4m: příkaz nenalezen
pgmtoy4m: команда не найдена
pgmtoy4m: командата не е открита
pgmtoy4m: 命令找不到
pgmtoy4m: コマンドが見つかりません