This is an idea to create a playlist from an Icecast server storing the songdata and cover image into a database.

IceCastPlaylist.php

<?php

/**
 * Class IceCastPlaylist
 * See https://stackoverflow.com/questions/60502076/how-to-get-icecast-server-songs-history/60798774#60798774 for context
 * 
 * This class can be used as follows:
 * global $wpdb
 * $playlistClass = new IceCastPlaylist($wpdb);
 * $playlistClass->fetchSongInfo();
 * $playlist = $songInfoClass->getPlaylist();
 * header('Content-Type: application/json;charset=utf-8');
 * echo $playlist;
 * die();
 */
class IceCastPlaylist {

	/**
	 * @var wpdb
	 */
	protected $db;

	/**
	 * @var string
	 */
	protected $table = '[replace with playlist table]';


	/**
	 * Replace this with your server URL
	 * @var string
	 */
	protected $songDataUrl = 'https://serveraddress:portnumber/stream.xspf';

	/**
	 * @var string
	 */
	protected $albumCoverUrl = 'https://itunes.apple.com/search?entity=musicTrack&term=';

	/**
	 * Replace this with your storage path
	 * @var string
	 */
	protected $albumCoverPath = '[absolute_path_to_cover_images_folder e.g /media/covers/]';

	/**
	 * Replace with your site URL
   * Most of the time you will want to set the URL to the site dynamically, 
   * so we do this in the constructor
	 */
	protected $siteUrl = '';

	/**
	 * Replace this with the desired length of your playlist
	 * @var int
	 */
	protected $playlistLength = 20;

	/**
	 * IceCastPlaylist constructor.
	 * In this case, I used WordPress wpdb, but it can be replaced with another DB instance
   * When using something else than wpdb, the query functions will need to be adjusted
	 *
	 * @param $db
	 */
	public function __construct(wpdb $db) {
		$this->db = $db;
    // If you need to set the site URL via a function, you can set it here in the constructor
		$this->siteUrl = get_site_url() . '/wp-content/media/covers/';
	}

	public function getPlaylist() {
		$result = $this->db->get_results("SELECT * FROM {$this->table} as songs ORDER BY `songs`.`id` DESC LIMIT {$this->playlistLength}");
		return json_encode($result);
	}

	/**
	 * [
	 *  'playedat' => 'H:i',
	 *  'title' => 'title',
	 *  'artist' => 'bla',
	 *  'coverImage' => 'linkToCoverArt',
	 *  'created_at' => 'Y-m-d',
	 * ]
	 * @param array $entry
	 */
	public function storeEntry(array $entry) {
		$this->db->insert($this->table, $entry);
	}

	/**
	 * @return mixed
	 * @throws Exception
	 */
	public function fetchSongInfo() {
		$rawData = file_get_contents($this->songDataUrl);
		$now = new DateTime('now');
		if(!$rawData) {
			throw new Exception('Error retrieving song data');
		}

		$xml = new SimpleXMLElement($rawData);
		$titleArtist = preg_split("/\s-\s/", (string) $xml->trackList->track->title);

		if($this->isNewSong($titleArtist[1])) {

			$stream['playedAt'] = $now->format('H:i');
			$stream['title'] = $titleArtist[1];
			$stream['artist'] = $titleArtist[0];
			$stream['coverImage'] = $this->getCoverArt($xml->trackList->track->title);
			$stream['created_at'] = $now->format('Y-m-d H:i:s');

			$this->storeEntry($stream);
		}
	}

	/**
	 * Use in your daily cleanup cron
	 */
	public function dailyCleanup() {
		$this->db->query("TRUNCATE TABLE {$this->table}");
	}

	/**
	 * @param string $title
	 *
	 * @return bool
	 */
	private function isNewSong(string $title) {
		$result = $this->db->get_results("SELECT * FROM {$this->table} as songs ORDER BY `songs`.`id` DESC LIMIT 1");
		if(empty($result)) {
			return true;
		}

		return $result[0]->title !== $title;
	}

	/**
	 * Take the raw 'songtitle - artist' and try to find cover art
	 * @param string $title
	 *
	 * @return string|null
	 */
	private function getCoverArt(string $title) {
		$itunesData = wp_remote_get($this->albumCoverUrl . urlencode($title), array(
			'timeout' => 45,
			'redirection' => 5,
			'httpversion' => '1.0',
			'blocking' => true,
			'headers' => array(
				'accept-encoding' => 'gzip, deflate, br',
				'pragma' => 'no-cache',
				'accept-language' => 'en-US,en;q=0.8',
				'user-agent' => 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.101 Safari/537.36',
				'accept' => 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8'
			),
			'cookies' => array(),
		));

		$songInfo = json_decode(trim(wp_remote_retrieve_body($itunesData)));
		$imageHash = '';
		if(isset($songInfo->results[0])) {
			$coverImage = str_replace('100x100bb.jpg', '', $songInfo->results[0]->artworkUrl100);
			$imageHash = md5($title) . '.jpg';
			if(!file_exists($this->albumCoverPath . $imageHash) && $coverImage !== '') {
				$img = file_get_contents($coverImage . '200x200bb.jpg');
				file_put_contents($this->albumCoverPath . $imageHash, $img);
			}
		}

		return (empty($imageHash)) ? null :  $this->siteUrl . $imageHash;
	}
}