NtM Chart-correction XML

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XML chart correction examples for comparison


French XML

Description by Shom: NtM chart corrections in XML are produced since the beginning of 2018, with CARIS “Publication module” customized for Shom. They are used by our internal process for the production of our weekly NtM booklet (pdf) and NtM website. The XML also contains some internal data. The XML doesn’t contain the chart correction number. It is added later in the process as well as the link with the tracing and with the possible NtM block (graphical chart-updating). One NtM may concern several charts to be updated. The XML refers to a font (TrueTypeFont) for the graphical feature which is subject of the instruction. The chart corrections are in French and a glossary French-English is available in our weekly NtM booklet and NtM website [(http://gan.shom.fr/ganl/htdocs/FR_home.htm)]. We also convert the XML in GML for internal checking purposes using the geometry of NtM (graphical display). In the examples below, one file containts the chart corrections for one weekly NtM booklet.

Examples: File:Xml fr.zip

Contacts: pierre-yves.le.moigne@shom.fr, jonathan.mouton@shom.fr

Comments:




German XML

Description by BSH


Examples File:DE xml.zip

Contacts: daniel[dot]zuehr[at]bsh[dot]de

Comments:




Italian NtM

Dwscription by Italian HO

Examples File:Italian NtM.zip


Contacts: ludovico_sturla[at]marina[dot]difesa[dot]it


Comments:






Conventions Summary


Conventions

Multiple use of XML, Notice(s) applicable for one chart, notice applicable for several charts

The data model to be developed should be able to handle both versions. If the setup is such, that every chart-correction can have a reference to one or several charts [1..*], it is up to the producer to decide whether corrections are repeated chart-by-chart or each correction has a reference to all affected charts. The German XML version shows that it should be possible to create a data structure that supports both versions.

UML Diagram

Simplified UML Diagram presenting the conceptual structure of a Notice to mariner in the FTA- system.

UML NtM conceptual structure.png

Notice

Each NoticeToMariner represents one single Notice.

NoticeContent

Each notice can contain any number of NoticeContent. NoticeContent is an abstract object, which can represent any of three types of content.

  • TextContent is a simple text-field, that can store simple (unformatted) text.
  • ImageContent is any image added to the notice. Usually these are images of the chart to be corrected.
  • ChartCorrectionContent is a complex structure that includes a combination of an S-4 standard action (ADD, DELETE etc.), INT- symbols, standard phrases /commands and additional textual explanations.

Each NoticeContent has a reference to a ChartImage, which in turn has a reference to the ChartProduct it belongs to. A chart product is here assumed to be a given edition of a chart.

ChartCorrectionContent

The ChartCorrectionContent is the structure holding the actual chart-correction. The table below shows the tabular display translation of one ChartCorrectionContent, with 3 ChartCorrectionTextrows and 5 ChartCorrectionPositions

  • The first row could contain INT- symbols and a textual note, which are attributes of ChartCorrectionContent
  • The following rows could contain data stored in ChartCorrectionTextrows
Action
objectA objectB row_note
textA textB row_note
textA textB row_note
textA textB row_note
  1. lat lon description
  2. lat lon description
  3. lat lon description
  4. lat lon description
  5. lat lon description

Images and Symbols

Format

TIFF
PNG
SVG

LS: Italy prefers to have them in a true type font format (like Arial, Times New Roman etc). They can be easily managed by all the production systems, while I see difficulties of tiff and svg formats.
How to display a wreck with the least depth known? With a tiff image of a general wreck and beside the text with the depth value and Wk abbreviation?

JS-F: The True Type Format could be seen as along term goal. Germany could possibly provide a tool which generates TIFF images for symbols with variable values on the fly. However, the XML should be written in a way that the symbols format is of less relevance. More inportant is to check the IHO capability to host a set of symbols and the provision of a "text description" of each symbol. The latter could be used as a universal translation tool between different symbol libraries.

Repository

Symbols can be stored by each HO individually.
Should we try to convince the IHO Secretariat to host a repository (database) of symbols (similar to INT1) in a discrete format (to be defined) and a textual description associated to each symbol?
HOs can then download the data sets and use them in their production systems. It should be discussed how the generation/drawing of symbols can be managed. Is an appropriate online tool available on the market? Should we approach the Secretariat to contract the developement of such an online tool? Can HO(s) volunteer to contract the development?

Generation

use of predefined set(s)
customise as appropriate, e.g. depth with depth contour



Status of correction

Following status versions are appliable:
Published PUBLISHED notices are those, which are in force.

Cancelled CANCELLED notices are those, which are cancelled by a new notice.
CANCELLED notices are those, which are not showing up on the "T&P in force" list.

Deactivated DEACTIVATED notices are those, which are not active anymore due to any several (internal or external) reasons, e.g. a new edition of a chart makes it superfluous
DEACTIVATED notices are those, which are not showing up on the "T&P in force" list

Chart corrections and General notifications

Chart corrections

Instruction where to place a block, e.g ADD block in position xxx.xxx, yyy.yyy
Instructions according to IHO Standard M-4
Use of GML coordinate encoding at the backend but at the front end the coordinates should be presented as 00°00,000'N 000°00,000'E, less decimals are possible if source or chart scale make it necessary

Do we need to provide information on corrections of corrections (Pierre-Yves raises this question)? Or can we say that all corrections are independant corrections and if one needs to correct erratums, a new correction should be generated without mentioneing that it corrects erratums?

Stefan: In the FI system is a function for a notice to cancel another previously published notice. We are using this functionality for corrections to previous notices.
Also re-issuing or cancelling T&P notices is made using this same functionality

P&T Notices

It should be no difference between T&P and regular notices. All notices are similar in structure, and only an attribute flag is indicating a notice as T or P.

P&T notices can have following status:
PUBLISHED - in force
CANCELLED - no longer in force due to cancellation by another P&T notice, or by a full notice (appropriate information must be provided)
DEACTIVATED- no longer in force due to HO internal processes (appropriate information must not be provided)

General notification

The question is here, are general notification messages such as "New Chart/Edition"?

Language

The corrections should be provided in multiple languages.

SE: In the UML there is a separate class MultilangString to indicate which attributes currently need to be provided in several languages. For example chart-texts are not translated. I think the easiest way to achieve support for several languages would be to provide each language in a separate file.

Block correction

Block corrections are to be created as separate geo-referenced PDF-documents / files.

A link to the block is added to the Notice. The provision of the block centre geo-reference is optional.

The separate geo-referenced PDF-documents / files should also be made available for download.

Images providing correction advice

Larger images assisting the chart-correction can be added as ImageContent.