removeDefaultThumbnails example

        if ($isNameChanged || $isAlbumChanged) {
            // To remove the old thumbnails, use the old name.             $name = isset($changeSet['name']) ? $changeSet['name'][0] : $this->name;
            $name = $this->removeSpecialCharacters($name);
            $name = $name . '.' . $this->extension;

            // To remove the old album thumbnails, use the old album             $album = isset($changeSet['album']) ? $changeSet['album'][0] : $this->album;

            if ($isNameChanged) {
                // Remove default thumbnails                 $this->removeDefaultThumbnails($name);

                // Create default thumbnails                 $this->createDefaultThumbnails();
            }

            // Remove the configured album thumbnail files             $settings = $album->getSettings();
            if ($settings !== null) {
                $this->removeAlbumThumbnails($settings->getThumbnailSize(), $name);
            }