diff --git a/CHANGELOG.md b/CHANGELOG.md
index 050f4fe9b..ed099414d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+* `icon` support for `Audio` and `Video` attachments
 * Send "new follower" emails
 
 ### Improved
diff --git a/includes/functions.php b/includes/functions.php
index 32eb34a18..d16a30bf7 100644
--- a/includes/functions.php
+++ b/includes/functions.php
@@ -822,6 +822,9 @@ function object_to_uri( $data ) {
 
 	// Return part of Object that makes most sense.
 	switch ( $type ) {
+		case 'Image':
+			$data = $data['url'];
+			break;
 		case 'Link':
 			$data = $data['href'];
 			break;
diff --git a/includes/transformer/class-post.php b/includes/transformer/class-post.php
index a14490075..40239f0e9 100644
--- a/includes/transformer/class-post.php
+++ b/includes/transformer/class-post.php
@@ -13,6 +13,7 @@
 use Activitypub\Collection\Actors;
 
 use function Activitypub\esc_hashtag;
+use function Activitypub\object_to_uri;
 use function Activitypub\is_single_user;
 use function Activitypub\get_enclosures;
 use function Activitypub\get_upload_baseurl;
@@ -208,7 +209,63 @@ protected function get_image() {
 		 */
 		$thumbnail = apply_filters(
 			'activitypub_get_image',
-			self::get_wordpress_attachment( $id, $image_size ),
+			$this->get_wordpress_attachment( $id, $image_size ),
+			$id,
+			$image_size
+		);
+
+		if ( ! $thumbnail ) {
+			return null;
+		}
+
+		$mime_type = \get_post_mime_type( $id );
+
+		$image = array(
+			'type'      => 'Image',
+			'url'       => \esc_url( $thumbnail[0] ),
+			'mediaType' => \esc_attr( $mime_type ),
+		);
+
+		$alt = \get_post_meta( $id, '_wp_attachment_image_alt', true );
+		if ( $alt ) {
+			$image['name'] = \wp_strip_all_tags( \html_entity_decode( $alt ) );
+		}
+
+		return $image;
+	}
+
+	/**
+	 * Returns an Icon, based on the Featured Image with a fallback to the site-icon.
+	 *
+	 * @return array|null The Icon or null if no icon is available.
+	 */
+	protected function get_icon() {
+		$post_id = $this->wp_object->ID;
+
+		// List post thumbnail first if this post has one.
+		if ( \has_post_thumbnail( $post_id ) ) {
+			$id = \get_post_thumbnail_id( $post_id );
+		} else {
+			// Try site_logo, falling back to site_icon, first.
+			$id = get_option( 'site_icon' );
+		}
+
+		if ( ! $id ) {
+			return null;
+		}
+
+		$image_size = 'thumbnail';
+
+		/**
+		 * Filter the image URL returned for each post.
+		 *
+		 * @param array|false $thumbnail  The image URL, or false if no image is available.
+		 * @param int         $id         The attachment ID.
+		 * @param string      $image_size The image size to retrieve. Set to 'large' by default.
+		 */
+		$thumbnail = apply_filters(
+			'activitypub_get_image',
+			$this->get_wordpress_attachment( $id, $image_size ),
 			$id,
 			$image_size
 		);
@@ -273,7 +330,7 @@ protected function get_attachment() {
 			$media = $this->get_classic_editor_images( $media, $max_media );
 		}
 
-		$media      = self::filter_media_by_object_type( $media, \get_post_format( $this->wp_object ), $this->wp_object );
+		$media      = $this->filter_media_by_object_type( $media, \get_post_format( $this->wp_object ), $this->wp_object );
 		$unique_ids = \array_unique( \array_column( $media, 'id' ) );
 		$media      = \array_intersect_key( $media, $unique_ids );
 		$media      = \array_slice( $media, 0, $max_media );
@@ -288,7 +345,7 @@ protected function get_attachment() {
 		 */
 		$media = \apply_filters( 'activitypub_attachment_ids', $media, $this->wp_object );
 
-		$attachments = \array_filter( \array_map( array( self::class, 'wp_attachment_to_activity_attachment' ), $media ) );
+		$attachments = \array_filter( \array_map( array( $this, 'wp_attachment_to_activity_attachment' ), $media ) );
 
 		/**
 		 * Filter the attachments for a post.
@@ -361,7 +418,7 @@ protected function get_block_attachments( $media, $max_media ) {
 
 		$blocks = \parse_blocks( $this->wp_object->post_content );
 
-		return self::get_media_from_blocks( $blocks, $media );
+		return $this->get_media_from_blocks( $blocks, $media );
 	}
 
 	/**
@@ -372,11 +429,11 @@ protected function get_block_attachments( $media, $max_media ) {
 	 *
 	 * @return array The image IDs.
 	 */
-	protected static function get_media_from_blocks( $blocks, $media ) {
+	protected function get_media_from_blocks( $blocks, $media ) {
 		foreach ( $blocks as $block ) {
 			// Recurse into inner blocks.
 			if ( ! empty( $block['innerBlocks'] ) ) {
-				$media = self::get_media_from_blocks( $block['innerBlocks'], $media );
+				$media = $this->get_media_from_blocks( $block['innerBlocks'], $media );
 			}
 
 			switch ( $block['blockName'] ) {
@@ -587,7 +644,7 @@ protected function get_classic_editor_image_attachments( $max_images ) {
 	 *
 	 * @return array The filtered media IDs.
 	 */
-	protected static function filter_media_by_object_type( $media, $type, $wp_object ) {
+	protected function filter_media_by_object_type( $media, $type, $wp_object ) {
 		/**
 		 * Filter the object type for media attachments.
 		 *
@@ -612,7 +669,7 @@ protected static function filter_media_by_object_type( $media, $type, $wp_object
 	 *
 	 * @return array The ActivityPub Attachment.
 	 */
-	public static function wp_attachment_to_activity_attachment( $media ) {
+	public function wp_attachment_to_activity_attachment( $media ) {
 		if ( ! isset( $media['id'] ) ) {
 			return $media;
 		}
@@ -635,7 +692,7 @@ public static function wp_attachment_to_activity_attachment( $media ) {
 				 */
 				$thumbnail = apply_filters(
 					'activitypub_get_image',
-					self::get_wordpress_attachment( $id, $image_size ),
+					$this->get_wordpress_attachment( $id, $image_size ),
 					$id,
 					$image_size
 				);
@@ -674,7 +731,11 @@ public static function wp_attachment_to_activity_attachment( $media ) {
 					$attachment['width']  = \esc_attr( $meta['width'] );
 					$attachment['height'] = \esc_attr( $meta['height'] );
 				}
-				// @todo: add `icon` support for audio/video attachments. Maybe use post thumbnail?
+
+				if ( $this->get_icon() ) {
+					$attachment['icon'] = object_to_uri( $this->get_icon() );
+				}
+
 				break;
 		}
 
@@ -697,7 +758,7 @@ public static function wp_attachment_to_activity_attachment( $media ) {
 	 *
 	 * @return array|false Array of image data, or boolean false if no image is available.
 	 */
-	protected static function get_wordpress_attachment( $id, $image_size = 'large' ) {
+	protected function get_wordpress_attachment( $id, $image_size = 'large' ) {
 		/**
 		 * Hook into the image retrieval process. Before image retrieval.
 		 *
@@ -920,7 +981,7 @@ protected function get_content() {
 		 */
 		do_action( 'activitypub_before_get_content', $post );
 
-		add_filter( 'render_block_core/embed', array( self::class, 'revert_embed_links' ), 10, 2 );
+		add_filter( 'render_block_core/embed', array( $this, 'revert_embed_links' ), 10, 2 );
 
 		// phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
 		$post    = $this->wp_object;
@@ -1119,7 +1180,7 @@ public function get_summary_map() {
 	 *
 	 * @return string A block level link
 	 */
-	public static function revert_embed_links( $block_content, $block ) {
+	public function revert_embed_links( $block_content, $block ) {
 		if ( ! isset( $block['attrs']['url'] ) ) {
 			return $block_content;
 		}
diff --git a/integration/class-seriously-simple-podcasting.php b/integration/class-seriously-simple-podcasting.php
index 8ca343b45..167af7e3e 100644
--- a/integration/class-seriously-simple-podcasting.php
+++ b/integration/class-seriously-simple-podcasting.php
@@ -9,6 +9,7 @@
 
 use Activitypub\Transformer\Post;
 
+use function Activitypub\object_to_uri;
 use function Activitypub\generate_post_summary;
 
 /**
@@ -35,9 +36,13 @@ public function get_attachment() {
 			'name' => \esc_attr( \get_the_title( $post->ID ) ?? '' ),
 		);
 
-		$cover = \get_post_meta( $post->ID, 'cover_image', true );
-		if ( $cover ) {
-			$attachment['icon'] = \esc_url( $cover );
+		$icon = \get_post_meta( $post->ID, 'cover_image', true );
+		if ( ! $icon ) {
+			$icon = $this->get_icon();
+		}
+
+		if ( $icon ) {
+			$attachment['icon'] = \esc_url( object_to_uri( $icon ) );
 		}
 
 		return array( $attachment );
diff --git a/readme.txt b/readme.txt
index e5a5d8dc8..ea0b95adb 100644
--- a/readme.txt
+++ b/readme.txt
@@ -134,6 +134,7 @@ For reasons of data protection, it is not possible to see the followers of other
 
 = Unreleased =
 
+* Added: `icon` support for `Audio` and `Video` attachments
 * Added: Send "new follower" emails
 * Improved: Email templates for Likes and Reposts
 * Improved: Interactions moderation
diff --git a/tests/includes/transformer/class-test-post.php b/tests/includes/transformer/class-test-post.php
index e9903b21c..63cb574cf 100644
--- a/tests/includes/transformer/class-test-post.php
+++ b/tests/includes/transformer/class-test-post.php
@@ -438,4 +438,79 @@ public function create_upload_object( $file, $parent_id = 0 ) {
 
 		return $id;
 	}
+
+	/**
+	 * Test get_icon method.
+	 *
+	 * @covers ::get_icon
+	 */
+	public function test_get_icon() {
+		$post_id = $this->factory->post->create(
+			array(
+				'post_title'   => 'Test Post',
+				'post_content' => 'Test content',
+			)
+		);
+		$post    = get_post( $post_id );
+
+		// Create test image.
+		$attachment_id = $this->create_upload_object( dirname( __DIR__, 2 ) . '/assets/test.jpg' );
+
+		// Set up reflection method.
+		$reflection = new ReflectionClass( Post::class );
+		$method     = $reflection->getMethod( 'get_icon' );
+		$method->setAccessible( true );
+
+		// Test with featured image.
+		set_post_thumbnail( $post_id, $attachment_id );
+
+		$transformer = new Post( $post );
+		$icon        = $method->invoke( $transformer );
+
+		$this->assertIsArray( $icon );
+		$this->assertEquals( 'Image', $icon['type'] );
+		$this->assertArrayHasKey( 'url', $icon );
+		$this->assertArrayHasKey( 'mediaType', $icon );
+		$this->assertEquals( get_post_mime_type( $attachment_id ), $icon['mediaType'] );
+
+		// Test with site icon.
+		delete_post_thumbnail( $post_id );
+		update_option( 'site_icon', $attachment_id );
+
+		$icon = $method->invoke( $transformer );
+
+		$this->assertIsArray( $icon );
+		$this->assertEquals( 'Image', $icon['type'] );
+		$this->assertArrayHasKey( 'url', $icon );
+		$this->assertArrayHasKey( 'mediaType', $icon );
+		$this->assertEquals( get_post_mime_type( $attachment_id ), $icon['mediaType'] );
+
+		// Test with alt text.
+		$alt_text = 'Test Alt Text';
+		update_post_meta( $attachment_id, '_wp_attachment_image_alt', $alt_text );
+
+		$icon = $method->invoke( $transformer );
+
+		$this->assertIsArray( $icon );
+		$this->assertEquals( 'Image', $icon['type'] );
+		$this->assertArrayHasKey( 'name', $icon );
+		$this->assertEquals( $alt_text, $icon['name'] );
+
+		// Test without any images.
+		delete_post_thumbnail( $post_id );
+		delete_option( 'site_icon' );
+		delete_post_meta( $attachment_id, '_wp_attachment_image_alt' );
+
+		$icon = $method->invoke( $transformer );
+		$this->assertNull( $icon );
+
+		// Test with invalid image.
+		set_post_thumbnail( $post_id, 99999 );
+		$icon = $method->invoke( $transformer );
+		$this->assertNull( $icon );
+
+		// Cleanup.
+		wp_delete_post( $post_id, true );
+		wp_delete_attachment( $attachment_id, true );
+	}
 }