CONTEXT-BASED SPEAKER COUNTER FOR A SPEAKER DIARIZATION SYSTEM

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for determining the number of speakers in a video and a corresponding audio using visual context. In one aspect, a method includes detecting within the video multiple speakers, determining a bounding box for each detected speaker that includes the detected person and objects within a threshold distance of the detected person in an image frame, determining a unique descriptor for that person based in part on image information depicting the objects within the bounding box, determining a cardinality of unique speakers in the video, providing to the speaker diarization system the cardinality of unique speakers.