1. A method for multimedia content generation, comprising: receiving a textual input; before receiving an audio narration of the textual input, estimating occurrence times of respective components of the audio narration; automatically retrieving from one or more media databases a plurality of media items that are relevant to the textual input; receiving user input, which selects one or more of the automatically-retrieved media items and correlates one or more of the selected media items in time with the textual input; and automatically constructing a video clip, which comprises the audio narration and the selected media items scheduled in accordance with the user input, by scheduling the selected media items in accordance with the estimated occurrence times.
8. The method according to claim 1 , wherein automatically constructing the video clip comprises training a scheduling model using a supervised learning process, and scheduling the selected media items in accordance with the trained model.