Sound effects (SFX) are registered in a database for efficient search and retrieval. This may be accomplished by classifying SFX and using a machine learning engine to output a first of the classified SFX for a first computer simulation based on learned correlations between video attributes of the first computer simulation and the classified SFX. Subsequently, videos without sound may be processed for object, action, and caption recognition to generate video tags which are semantically matched with SFX tags to associate SFX with the video.