Closed Captions

Enable closed captioning support in MPlatform and in your broadcast playout solution.

Closed captioning (or CC) is the process of displaying text on a video screen or any visual display to provide the viewers with a transcription of all significant audio content, such as dialogue and sound effects. Captions are synchronized with the video image to ensure full understanding. In contrast to open captions, closed captions can be turned on/off by the viewer. Additional information about CC is available here.


Closed captioning is obligatory for the majority of programming on broadcast TV in the United States, Canada and China, as well as in most Latin American countries.


Closed Captions lib, when used together with MPlatform, allows to play out files with captions to Blackmagic and Deltacast I/O devices via composite or SDI connection; it also allows to capture CC data from Blackmagic hardware.


Supported CC standards


  • CEA-608 (NTSC)
  • CEA-708 (digital television)


Supported file formats


  • .SCC and .MCC files;
  • MPEG-2 PS/TS (EIA-608, CEA-708);
  • QuickTime/MP4 (EIA-608);
  • LXF HD;
  • MXF SD;
  • Burned-in line 21 picture with 720x486 frame size;
  • MPEG-2 / H.264 video stream with ATSC Closed Captions;
  • Files with CDP.


CC capturing


  • CEA-608 data is captured into .SCC file with the same name.
  • CEA-708 data is captured into custom .ACC file supported by MPlatfom.