Metadata-based diarization of teleconferences

A method for audio processing, comprising:

• receiving, in a computer, a recording of a teleconference among multiple participants over a network, the recording including an audio stream containing speech uttered by the participants and a visual component of the teleconference recording;
• processing the audio stream by the computer to identify speech segments, in which one or more of the participants were speaking, interspersed with intervals of silence in the audio stream;
• extracting speaker identifications, which are indicative of the participants who spoke during periods of the teleconference from the visual component of the teleconference recording;
• labeling a first set of the identified speech segments from the audio stream with initial speaker identifications, wherein each speech segment from the audio stream, in the first set, is labelled with a speaker identification of a period corresponding to a time of the speech segment;
• extracting acoustic features from the speech segments in the first set;
• learning a correlation between the speaker identifications labelled to the segments in the first set, and the extracted acoustic features extracted from the corresponding segments of the first set;
• and
• relabeling one or more of the identified speech segments of the first set, using the learned correlation.

Apparatus for audio processing, comprising:

• a memory, which is configured to store a recording of a teleconference among multiple participants over a network, the recording including an audio stream containing speech uttered by the participants and information outside the audio stream;
• and
• a processor, which is configured to:
• process the audio stream so as to identify speech segments, in which one or more of the participants were speaking, interspersed with intervals of silence in the audio stream,
• extract speaker identifications, which are indicative of the participants who spoke during periods of the teleconference from the information outside the audio stream in the received recording, so as to provide for a plurality of the periods of the teleconference, corresponding speaker identifications,
• label a first set of the identified speech segments from the audio stream with the speaker identifications extracted from the information outside the audio stream in the received recording, wherein each speech segment from the audio stream, in the first set, is labelled with a speaker identification of a period corresponding to a time of the speech segment;
• extract acoustic features from the speech segments in the first set;
• learn a correlation between the speaker identifications labelled to the segments in the first set, and the extracted acoustic features extracted from the corresponding segments of the first set;
• and
• relabel one or more of the identified speech segments of the first set, using the learned correlation, to indicate the participants who spoke based on the learned correlation instead of the speaker identifications extracted from the information outside the audio stream.