1. A computer-implemented method of assessing emotional responses of a panel of individuals to a user-defined event in a presentation, the method carried out by a computer system performing computer processes comprising: associating, with a first file, a first video recording and an audio recording being made of a presentation captured by a first camera and, with a second file, a second video recording being made of the panel observing the presentation captured by a second camera; storing the first and second files in a database, in association with a session identifier for the presentation; receiving, by the computer system, for each individual in the panel, an identified location of such individual in an image captured by the second camera; storing the identified locations in the database in association with the session identifier; completing recordation of content of the presentation in the first and second files; during or after the recordation, receiving and storing, in association with the session identifier, a user input flagging a beginning and an ending for the event; for each frame in a set of frames in the second video recording of the panel observing the presentation, processing the second file by: (a) sending such frame to an emotion analyzer subsystem; (b) receiving, from the emotion analyzer subsystem, a data array for such frame that for each face in such frame, specifies a location of such face in the frame and emotional expression data corresponding to an emotional expression of such face; (c) matching the location of each face in the data array with the corresponding location of the identified individual; and (d) storing in the database, for each face in the data array for which there is a match with the corresponding identified individual, the emotional expression data and an identifier for the frame in association with the corresponding identified individual; using the beginning and ending flags to identify frames associated with the event; using the identified frames to locate and extract, from the database, emotional expression data for the set of individuals of interest associated with the event; and displaying the extracted data.