dvcont: 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 CentOS possible default full paths are:

/usr/bin/dvcont - from package: libavc1394

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/dvcont - from package: libavc1394-tools

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

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