jaaniic'ša pierakstu klade

$homepage = file_get_contents('https://gdata.youtube.com/feeds/api/videos?q='.urlencode($dz_izpilditajs).'%20-%20'.urlencode($dz_nosaukums).'&orderby=relevance&start-index=1&max-results=1&v=2&alt=json');
$ytraw=json_decode($homepage, true);
$here = explode(":", $ytraw['feed']['entry'][0]['id']['$t']);
$num = (count($here) - 1);
$yt = $here[$num];

Vairāk info šeit:
https://developers.google.com/youtube/2.0/developers_guide_protocol_api_query_parameters?hl=cs

preg_match('#(?:http://)?(?:www\.)?(?:youtube\.com/(?:embed/|v/|watch\?v=)|youtu\.be/)([\w-]+)(?:\S+)?#', $string, $match);

$url="http://www.youtube.com/watch?v=mHifGmeToVU";
parse_str(parse_url($url,PHP_URL_QUERY),$my_array);
echo $my_array['v'];
echo "<img alt="" src="http://img.youtube.com/vi/&quot;.$my_array[" />";
VAI
function youtube_id_from_url($url) {
$pattern =
'%^# Match any youtube URL
(?:https?://)? # Optional scheme. Either http or https
(?:www\.)? # Optional www subdomain
(?: # Group host alternatives
youtu\.be/ # Either youtu.be,
| youtube\.com # or youtube.com
(?: # Group path alternatives
/embed/ # Either /embed/
| /v/ # or /v/
| /watch\?v= # or /watch\?v=
) # End path alternatives.
) # End host alternatives.
([\w-]{10,12}) # Allow 10-12 for 11 char youtube id.
$%x'
;
$result = preg_match($pattern, $url, $matches);
if (false !== $result) {
return $matches[1];
}
return false;
}

echo youtube_id_from_url(‘http://youtu.be/NLqAF9hrVbY’); # NLqAF9hrVbY

http://img.youtube.com/vi//0.jpg
http://img.youtube.com/vi//1.jpg
http://img.youtube.com/vi//2.jpg
http://img.youtube.com/vi//3.jpg

http://img.youtube.com/vi//default.jpg

http://img.youtube.com/vi//hqdefault.jpg

http://img.youtube.com/vi//mqdefault.jpg

http://img.youtube.com/vi//sddefault.jpg

http://img.youtube.com/vi//maxresdefault.jpg