lavinfo: 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/lavinfo - from package: mjpegtools

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

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