A system that predicts viewers` reaction to films developed in Łódź

We believe that it is possible to predict the viewer`s reaction without an actual viewer, which will allow to improve the frames or compositions so that the picture is more interesting, says Dr. Piotr Napieralski, head of the Department of Computer Graphics and Multimedia at Lodz University of Technology.

Part of the project consisted in studying the reactions of viewers. For this purpose, researchers used devices currently widely used in the gaming industry. It was an eyetracker, a device that tracks the viewer`s eyes and checks at which point of the screen the viewer is looking, and Brain Computer Interface, a device that allows to control the computer with the user`s thoughts, based on a simplified EEG model.

"Both devices were used to acquire signals from the viewer. On this basis, we were able to follow the areas of the image that the viewer found interesting, and the emotions that accompanied the viewer during watching (...)" - explains the project leader.

At the same time - but without the participation of viewers - the scientists created synthetic viewers` interests. They used artificial intelligence algorithms and image processing algorithms. In this way they built saliency maps, which show - in a way similar to thermal maps - the distribution of important places in the film image, to which viewers pay attention.

"In addition to strong focal point, people pay attention to movement, faces, colouring and letters. All this had to be combined into a map that would correspond to real viewer`s reactions a moving image" - explains Dr. Napieralski.

The saliency maps were verified - scientists checked whether the film analysed this way was actually consistent with the research carried out with viewers. According to scientists, it turned out that this method works.

"In the case of the majority of films that we verified with our methods, it turned out that the results were roughly consistent with the real viewer`s reactions to the film" - emphasises the head of the Department of Computer Graphics and Multimedia.

Research with the software created by the specialists from Lodz University of Technology confirms, for example, that viewers watching a film pay attention to faces, and sudden movement immediately attracts their attention. Interestingly, men and women reacted differently. "Women avoided the eyes of the characters in the film, while men followed the eyes" - adds Dr. Napieralski.

Researchers studied various groups of viewers - students, people from the computer games industry and filmmakers. It turned out that there were significant differences between them in terms of image perception and reactions - for example, filmmakers perceived the image very analytically and technically, and non-industry people reacted more emotionally.

According to Dr. Napieralski, synthetic building of a saliency map based on a film image allows to check the areas that are more or less important to the viewer, find out, which shots can be important. This is of great importance in film production, where every hour of the film set generates enormous costs.

The ability to quickly verify a film using synthetic images instead of conducting viewer surveys allows to quickly eliminate errors, for example during editing or post-production.

Researchers from Łódź continue to work on their software with the use of devices that allow to verify more signals from viewers watching a film. The inventors believe that in the future their system could be used on film sets. (PAP)

author: Kamil Szubański

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