function vid_length()
{
    yecho "Running mencoder "$1" -quiet -ovc copy -oac pcm -o /dev/null | awk '/Video stream/ {print $10}'" >> "$LOG_FILE"
    mencoder "$1" -quiet -ovc copy -oac pcm -o /dev/null 2>>"$LOG_FILE" | awk '/Video stream/ {print $10}'
}