Closed Captioning (sometimes called “captions”) are the textual representation of a video’s audio content. They are critical for viewers who suffer from hearing loss, and they are also a great tool for improving the reading and listening skills of others Captions include sound effects such as background noise, sirens, doors slamming, or phones ringing that give the viewer a greater appreciation of the content.
Captions also help viewers watching in an “audio off” mode to better understand your video. Studies show that videos with captions are viewed longer than those that don’t. Finally, since search engines can’t index video, adding captions to your videos will ensure that they are indexed by search engines more quickly and accurately, meaning your video will reach more people.
Communication Access Realtime Translation (CART) is the instantaneous translation of the spoken word into readable text. Often called captioning, this text can be viewed on a mobile device, notebook computer, television monitor, or large screenallowing everyone to read along and participate.
CART is widely used in classrooms, counseling sessions, teleconferences, meetings, seminars, conferences, and trainings, and church services, just to name a few places. CART enables people who are hard of hearing and deaf equal access to fully and actively participate in discussions by reading the text displayed. CART can also be helpful for with improving comprehension for people with processing issues as well as those for whom English is a second language.
There are two major styles of captions currently being used in the industry: pop-on and roll-up.
Pop-on captions are usually one or two lines of captions that appear onscreen and remain visible for one to several seconds before they disappear. Pop on captions are placed to help the viewer know who is speaking and are formatted to generally be complete sentences or thoughts.
Roll-up captions generally appear at the bottom of the screen and scroll up. Roll up captions are most often used with live programming.. Captions follow double chevrons (>>), and are used to indicate different speaker identifications. Each sentence “rolls up” to about three lines. The top line of the three disappears as a new bottom line is added, allowing the continuous rolling up of new lines of captions. Triple chevrons (>>>) usually indicate a topic change.
Captions afford viewers who may be deaf or hard of hearing access to televised programming, while offering the producer a much larger viewing audience. There are currently over one million deaf people in the United States, and over 28 million people affected by hearing loss.
Captioning has been related to higher comprehension skills when compared to viewers watching the same media without captions.
Captions provide missing information for individuals who have difficulty processing speech and auditory components of the visual media (regardless of whether this difficulty is due to a hearing loss or a cognitive delay).
Students often need assistance in learning content-relevant vocabulary (in biology, history, literature, and other subjects), and with captions they see both the terminology (printed word) and the visual image.
Closed captioning information is encoded within the video signal, in line 21 of the vertical blanking interval (VBI). The text only becomes visible with the use of a decoder, which is built into your television set or available as a set-top box for older tube televisions. In general, an onscreen menu on newer televisions allows you to turn closed captioning on or off, and most newer TV remotes have a dedicated closed captioning button.
Most programs are captioned in advance of transmission, but the nature of some programs, such as live news broadcasts, requires real-time captioning, in which a skilled captioner listens to the broadcast and types the show using a steno machine like a court reporter. That signal is sent to the television station’s closed captioning encoder, where it becomes embedded in the video of the broadcast. That is why there is usually a bit of a delay in live broadcasts between the captions and the program.