xscreensaver-getimage-video: 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/xscreensaver-getimage-video - from package: xscreensaver-base

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

On Debian possible default full paths are:

/usr/bin/xscreensaver-getimage-video - from package: xscreensaver-data

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

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