Wahrnehmung von grafischen Einblendungen in High Dynamic Range

Zusammenfassung des Vortrags

Dienstag, 4. Juni 2024
16:10 bis 17:50 Uhr

Saal 2: Themenblock Audio und HDR

Titel des Vortrags: Wahrnehmung von grafischen Einblendungen in High Dynamic Range - eine Nutzerstudie zu Helligkeitspräferenzen mit Fokus auf HDR-Broadcast-Inhalte 

More and more television screens currently available on the market are capable of displaying high dynamic range content. TV broadcasters are therefore faced with the task of adapting productions and production techniques accordingly. One topic that is largely overlooked in literature is that of graphic overlays and how they are perceived by viewers.

While on-screen-graphics in standard dynamic range are widely based on the luminance of reference white, the topic of HDR is concerned with the question of how these graphics should be adapted to the increased dynamic range. The aim of this master's thesis is therefore to investigate how graphic overlays and their luminance in HDR are perceived by viewers.

In a user study, 30 participants evaluated and graphically graded different on-screen-graphics on various HDR moving image sequences. The screen used was capable of displaying a maximum luminance of 1000 cd/m².

First it is shown that graphic overlays do not have to be adjusted in brightness for typical SDR content as preferred graphic whites result in a small corridor between 90 and 100 cd/m², with very few exceptions. The results in HDR however show a high variety of graphic white levels from 3.46 cd/m² up to the maximum of 1000 cd/m².

The resulting graphics luminance values are compared with the luminance statistics of the image sequences shown and a correlation between graphics and the average luminance of the different sequences is shown. This gives an outlook on how the issue presented in this paper can be managed in the future with regard to TV broadcasters and their production technologies.