The role of System Electronic Navigational Chart (SENC) in ECDIS

 The System Electronic Navigational Chart (SENC) plays a crucial role in the functioning of the Electronic Chart Display and Information System (ECDIS)¹.

ECDIS does not process the Electronic Navigational Chart (ENC) content directly for display. ENCs in S-57 format are optimized to absorb the Hydrographic object information, but this structure is not adequate for the fast generation of the resulting computer image on the screen¹.

To facilitate the rapid display of ENC data, ECDIS first converts each ENC from the S-57 ENC format into an internal format called SENC¹. This conversion results in efficient data structures optimized for chart image creating routines¹.

These routines are part of the individual software know-how of the ECDIS manufacturers, and hence, the SENC format differs between the ECDIS of different manufacturers¹. In contrast to the common uniform ENC format, the SENC format is proprietary for each ECDIS manufacturer¹.

Therefore, the SENC is the database that ECDIS accesses for the display generation and other navigational functions, and it is equivalent to an up-to-date paper chart².