Autofields WordPress Plugin
AutoFields Plugin will auto fill the Excerpt and add an Image custom field based on the data you entered into the contents editor. This plugin will set the first paragraph of the content as the excerpt and take the first image(if there are any) and set it as the ‘Image’ custom field(needed for some themes – like Mimbo – my theme). When you hit the publish button, it will check to make sure that excerpt and Image custom field are filled. If not, it will ask you to confirm before publishing the post.