Wednesday, 2 January 2013

Problems with 20 NOAA Charts

Several users have asked why certain charts they download from NOAA are being rejected by SEAiq Free/USA.  The issue is that NOAA has recently published 20 charts that are missing an important file.

The International Hydrographic Organization's S-57 chart standard requires that chart-sets include a special file with the name CATALOG.031.  This file serves as a kind of table-of-contents, defining what information is included and allows programs such as SEAiq to verify the contents.

The problematic charts from NOAA do not include a CATALOG.031 file, which is why the charts are being rejected.  SEAiq checks every chart downloaded from NOAA carefully before accepting it for use.  This is the pause you can see after each chart is downloaded. This helps protect, for instance, against an unusable chart from replacing a usable one.  And it lets you know that some of your charts may not be entirely up to date.

We have submitted a report to NOAA describing the issue.  Also, the next version of SEAiq Free/USA will include a work-around that makes an exception, to allow you do download the problematic charts until NOAA fixes them.

1 comment:

  1. Update: NOAA got back to us... the charts have been fixed.