While there are a variety of text-based options available, only time-synced, verbatim captions provide full and equal access to video content. Interpreting services, real-time captioning, or a printed transcript of a media source do not necessarily provide complete access, as stand alone services.
If the media being presented is interpreted by a sign language interpreter, access is incomplete because the interpreter and the video cannot be viewed at the same time. The viewer will need to shift their attention and gaze between the interpreter and the screen no matter how close the interpreter is situated to the screen, sometimes resulting in missed information.
Offline captioning refers to captions that are added in the post production process. Offline captioning allows for the most accurate captioning possible.
Audio captioning refers to captions that are created in real-time using automatic speech recognition technology to produce machine generated captions. This type of captioning has a higher rate of errors and should be used only when offline captioning is not possible.
Speech-to-text is an umbrella term used to describe an accommodation in which spoken communication and other auditory information are translated into text in real-time. A service provider types what is heard and the text appears on a screen for the consumer to read.
Open captions refers to captions that are part of the video image. They are always present and cannot be turned off.
Closed captions refers to captions that are encoded in the video signal. They can be turned on or off.
Subtitles are designed for hearing individuals who do not speak the language on the video. Subtitles translate the dialogue into another language for the viewer. They do not include cues to audible sounds, such as music or a doorbell ringing.
Subtitles for Deaf and Hard of Hearing is a phrase occasionally used to refer to captions. When this terminology is used, it is best to check that captions, rather than subtitles, are present.
Roll-up captions are used for live television broadcasting.begin at the bottom of the screen and scroll up two to three lines at a time. When the top line scrolls off the screen, a new line is added to the bottom. The scrolling motion can be difficult to read for extended periods of time
Pop-on captions are generally used for pre-recorded and online materials. They appear on the screen one to three lines at a time. This type is preferred because it is easier to read. and for accessibility purposes, pop-on captions are the preferred option as they are generally more time-synchronized, accurate, and descriptive than roll-up captions. Examples of both are offered at: https://www.3playmedia.com/2014/09/26/roll-up-vs-pop-on-captions-whats-difference/
The most efficient way to ensure media is captioned is to select media that is already captioned. Make sure to view the media for the presence of captions before making the final decision to show it in class. If the selected media is not captioned, attempt to find an equivalent source that is captioned.