Quest for Finding the Right HD Format: A New Psychophysical Method for Subjective HDTV Assessment

The availability of different HDTV image formats such as 720p/50 or 1080i/25 and 1080p/50 as a potential future format poses the question for many users on what HDTV format to use with which compression algorithm and at what bit rate. Subjective testing according to the well-know standards of the ITU-R BT.500–11 only provides the failure characteristic of each individual HDTV format. The European Broadcast Union (EBU) has developed a new subjective testing method called the triple stimulus continuous evaluation scale (TSCES) for HDTV formats and has used this method with over 300 assessors to investigate the various HDTV formats on different flat panel displays. H.264/AVC was used as a compression system at broadcast bit rates. Thus, comparative graphs between the different HDTV formats were possible and have shown that progressive scanning formats outperform HDTV with 1080i/25. Although the results have also proven that 720p/50 is currently the favorable emission format, there are also indicators for the potential of 1080p/50.