1. A method of detecting a composition of an audience of an information presenting device comprising: capturing at least one image of the audience; determining, using a processor, a number of people within the at least one image; prompting the audience to identify its members if a change in the number of people is detected based on the number of people determined to be within the at least one image; and if a number of members identified by the audience is different from the determined number of people after a predetermined number of prompts of the audience, adjusting, with the processor, a value to avoid excessive prompting of the audience.