Video intelligibility

The degree to which a video signal can be perceived and understood by the viewer, determined by technical parameters including frame rate, bit rate, spatial resolution, and codec quality. Video intelligibility is distinct from comprehension — a viewer may perceive clear hand movements in a sign language video (high intelligibility) but not understand the meaning if they are not fluent in the language (low comprehension). For sign language video communication, research has identified an intelligibility ceiling effect where increasing frame rate above 10fps or bit rate above 60kbps at 320x240 resolution does not significantly improve perceived intelligibility.