Ключевые слова: angle view, audience, auditorium, back, background, business, businessman, businesswoman, casual, communication, company, conference, conference hall, congress, corporate, crowd, education, entertainment, entrepreneurs, event, female, group, hall, head, indoor, large, lecture, light, listening, man, many people, meeting, people, podium, presentation, professional, public, rear view, seminar, side view, sitting, smartphone, speaker, stage, stage light, together, training, tribune, woman, workshop,