Custom template for events-manager-pro/templates/printables/pdf-part-logo.php

<td class="logo">
	<?php
	$logo_url = get_option( 'dbem_bookings_pdf_logo' );

	if ( $logo_url ) {

		$logo_path = '';

		// Convert WordPress uploads URL to a local filesystem path.
		$upload_dir = wp_upload_dir();

		if ( strpos( $logo_url, $upload_dir['baseurl'] ) === 0 ) {
			$logo_path = str_replace(
				$upload_dir['baseurl'],
				$upload_dir['basedir'],
				$logo_url
			);
		}

		if ( $logo_path && file_exists( $logo_path ) && is_readable( $logo_path ) ) {

			$mime = mime_content_type( $logo_path );
			$data = base64_encode( file_get_contents( $logo_path ) );

			echo '<img src="data:' . esc_attr( $mime ) . ';base64,' . $data . '" style="width:200px;">';

		} else {
			echo '<!-- PDF logo not found: ' . esc_html( $logo_url ) . ' -->';
		}

	} else {
		echo esc_html(
			get_option( 'dbem_bookings_pdf_logo_alt', get_bloginfo( 'name' ) )
		);
	}
	?>
</td>