If I have a YouTube video URL, is there any way to use PHP and cURL to get the associated thumbnail from the YouTube API?
Method 1:
You can find all information for a YouTube video with a JSON page which has even "thumbnail_url", http://www.youtube.com/oembed?format=json&url={your video URL goes here}
Like final URL look + PHP test code
$data = file_get_contents("https://www.youtube.com/oembed?format=json&url=https://www.youtube.com/watch?v=_7s-6V_0nwA");
$json = json_decode($data);
var_dump($json);
object(stdClass)[1]
public 'width' => int 480
public 'version' => string '1.0' (length=3)
public 'thumbnail_width' => int 480
public 'title' => string 'how to reminder in window as display message' (length=44)
public 'provider_url' => string 'https://www.youtube.com/' (length=24)
public 'thumbnail_url' => string 'https://i.ytimg.com/vi/_7s-6V_0nwA/hqdefault.jpg' (length=48)
public 'author_name' => string 'H2 ZONE' (length=7)
public 'type' => string 'video' (length=5)
public 'author_url' => string 'https://www.youtube.com/channel/UC9M35YwDs8_PCWXd3qkiNzg' (length=56)
public 'provider_name' => string 'YouTube' (length=7)
public 'height' => int 270
public 'html' => string '' (length=171)
public 'thumbnail_height' => int 360
For details, you can also see How to get a YouTube video thumbnail using id or https://www.youtube.com/watch?v=mXde7q59BI8 video tutorial 1
Method 2:
Using YouTube image link, https://img.youtube.com/vi/"insert-youtube-video-id-here"/default.jpg
Method 3:
Using browser source code for getting thumbnail using video URL link -go to video source code and search for thumbnailurl. Now you can use this URL into your source code:
{img src="https://img.youtube.com/vi/"insert-youtube-video-id-here"/default.jpg"}
For details you can also see How to get a YouTube video thumbnail using id or https://www.youtube.com/watch?v=9f6E8MeM6PI video tutorial 2