VANC, also known as Vertical Ancillary Data, is a term commonly used within the broadcasting and video production industries. It refers to a method of embedding additional data or information into the vertical blanking intervals (VBI) of a video signal.
The vertical blanking interval occurs during the vertical retrace phase of a television broadcast signal, where the electron beam of a CRT (cathode ray tube) television moves from the bottom of the screen to the top. This interval is not visibly displayed on the screen and provides an opportunity to insert supplementary data without affecting the actual video content.
VANC is utilized to embed various types of data, such as closed captions, timecodes, teletext, metadata, and other ancillary information, within the VBI. This additional data is crucial for various purposes, including accessibility, synchronization, metadata management, and transmission control.
By using VANC, broadcasters and video production professionals can seamlessly integrate important information into the video signal, ensuring that it is correctly synchronized and accessible to viewers. It enables the transmission of closed captions for the hearing impaired, timecodes for accurate editing and synchronization, and other types of data that enhance the viewer's experience or provide essential information to the production process.
Overall, VANC is a crucial technique in the broadcasting and video production industry, allowing for the inclusion of ancillary data within the vertical blanking intervals of a video signal, thus enhancing the viewing experience and facilitating various technical aspects of production and transmission.
