Web-based platform for a customizable and synchronized presentation of subtitles in single- and multi-screen scenarios

This paper presents a web-based platform for a customized and synchronized presentation of subtitles in both single- and multi-screen scenarios. The platform enables a dynamic user-level customization of subtitles in terms of format (font family, size, color, transparency...) and position, according to the users’ preferences and/or needs. It also allows adjusting the number of subtitle lines to be presented, being able to skip to the corresponding playout position of the beginning of a specific line by clicking on it. Likewise, multiple languages can be simultaneously presented, and a delay offset to the presentation of subtitles can be applied. All these functionalities can also be available on companion devices, by associating them to the session on the main screen. This enables the presentation of subtitles in a synchronized manner with the content on the main screen and their independent customization. The platform provides support for different subtitle formats, as well as for HTML5 and Youtube videos. It includes a module to upload videos and their subtitle files, and to manage playlists. Overall, the platform enables personalized and more engaging consumption experiences, contributing to improve the Quality of Experience (QoE). It can additionally provide benefits in a variety of scenarios, such as language learning, crowded multi-culture and noisy environments. The results from a subjective evaluation study, with the participation of 40 users without accessibility needs, reveal that the platform can provide relevant benefits for the whole spectrum of consumers. In particular, users have been very satisfied with the usability, attractiveness, effectiveness and usefulness of all features of the platform.