Collaborative method for quality evaluation of coded pictures

In order to avoid tiresome and tedious evaluation of coded pictures, collaborative subjective evaluation method using Internet is newly proposed. Except for observation conditions, evaluating environment including evaluation time, picture presentation sequence and evaluation word is matched with that of ITU-R recommendation. Experiments open to the students in our university was continued for 4 months on the Internet to get 100 voluntary testers. According to experimental result using 14 coded pictures, the order of pictures sorted by the collaborative MOS agreed with that by the MOS of the ITU-R recommendation when 60 voluntary testers collaborated. It was also found that we could predict the MOS of the ITU-R recommendation from the collaborative MOS with 80 voluntary testers or more.