Subtitles are fundamental for deaf users and useful for users who cannot enable sound. They can be read by the screen reader.
Objectives
Allow users who cannot access sound or deaf to have a visual alternative synchronized with the image for comfortable tracking of the video-unrolling without having to use an external transcript.
Make the empty accessible
Implementation
Associate with each empty content of synchronized subtitles with at least the information given by the speech.
Control
Enter, for each empty content that provides information by the speech, that it can be played via synchronized subtitles.