yuv2lav: 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/yuv2lav - from package: mjpegtools

You may install the required package with command apt-get install {package}
Error in other languages:
yuv2lav: bevel nie gevind nie
yuv2lav: comandă negăsită
yuv2lav: comando não encontrado
yuv2lav: commande introuvable
yuv2lav: command not found
yuv2lav: käsku ei ole
yuv2lav: không tìm thấy lệnh
yuv2lav: komanda nerasta
yuv2lav: Kommando nicht gefunden.
yuv2lav: kommandot finns inte
yuv2lav: komut yok
yuv2lav: nie znaleziono polecenia
yuv2lav: níor aimsíodh an t-ordú
yuv2lav: no se encontró la orden
yuv2lav: no s'ha trobat l'ordre
yuv2lav: opdracht niet gevonden
yuv2lav: parancs nem található
yuv2lav: perintah tidak ditemukan
yuv2lav: príkaz nenájdený
yuv2lav: příkaz nenalezen
yuv2lav: команда не найдена
yuv2lav: командата не е открита
yuv2lav: 命令找不到
yuv2lav: コマンドが見つかりません