Charts

[SailNomad]

Originally Posted by dacust

The REFs are the reference points. Known points that connect the pixel location to a geographic location.
-dan

• Besides corrolating pixels to lat-lons, do they serve any other purpose. i.e. is there a marker, text, whatever that i supposed to be on that location, as it is in the ARE tag ? or is it for calibration, and interpolation purposes only ?
  
• Is there a location that identifies all the tags in the KAP file ? I found some partial description on sourceforge, but that is all.

There seem to be several different color tags RGB, DAY, DSK, NGT, NGR, GRY, PRG, which are probably not of interest since I am not rendering the chart, just would like to find the chart(s) given a set of Lat/Lons , and perhaps annotate it.
A lot of them are deductable:
BSB: NA=name NU = ? (number?) RA= Raster area (chart size?) DU =
?
KNP SC=scale GD=datum PR=projection PP = projection parameter...

By the way, am I risking getting a hate-mail from Maptech for posting and investigating this ?
Thanks

[dacust]

Originally Posted by SailNomad

Besides corrolating pixels to lat-lons, do they serve any other purpose. i.e. is there a marker, text, whatever that i supposed to be on that location, as it is in the ARE tag ? or is it for calibration, and interpolation purposes only ?

Calibration, only

Originally Posted by SailNomad

Is there a location that identifies all the tags in the KAP file ? I found some partial description on sourceforge, but that is all.

That's the only one I know of. This one, here, right?

Originally Posted by SailNomad

By the way, am I risking getting a hate-mail from Maptech for posting and investigating this ?

We have been posting stuff about the BSB format for months. No hate mail, yet. But I did get an e-mail telling me I won $25 million in the Nigerian Lottery. I'll get it right after they get the registration fee I sent them.

-dan

[SailNomad]

Originally Posted by dacust

Calibration, only



That's the only one I know of. This one, here, right?


-dan

Yes that's the one.

I'll study the charts for a while when I get time. I already wrote a few linux scripts (mostly grep and sed and cut to take a directory of KAP files and create some sql entries to be able to corrolate region names to chart numbers.
I'l post my results here once I have something concrete, in case anybody is interested.

there is a hillerous website of a group that leads the Nigerians on to do all kinds of ridicilous things pretending that they are going to do the deal
(like ... I'd love the 25 Million, but you need to prove that you are real. Send me a naked picture with bunny rabbit ears on your head)
ANd these guys are actually doing it.
Dont' remember now what the website is.

[SailNomad]

This is what I was able to put together as a test:
www.boatjuggler.com/GTest1.php

Basically I wrote a simple linux script to create database entries for the charts and then wrote some PHP scripts to show the corners, and the NOAA chartviewer on the screen.
This is just a simple test and fairly straightforward. Let me know if anybody is interest in the details

[idpnd]

Originally Posted by SailNomad

there is a hillerous website of a group that leads the Nigerians on to do all kinds of ridicilous things pretending that they are going to do the deal
(like ... I'd love the 25 Million, but you need to prove that you are real. Send me a naked picture with bunny rabbit ears on your head)
ANd these guys are actually doing it.
Dont' remember now what the website is.

Welcome to the 419 Eater <- e.g.

[GPS-Marco]

A new version of CHARTCAL for you. Changes from V22 to V23 are on 12 maps:

NZ632, NZ681, NZ681_1, NZ4265, NZ4265_1, NZ5121,
NZ5225, NZ5225_1, NZ6152, NZ6152_1, NZ7624, NZ7624_1

Reason of change is that LINZ on Feb. 24th has released new versions of above map images (either for reprinting old charts or for adding some Notice To Mariners).

If you want them, download the new ChartCal V23 ( MCE66 - Software ) and rebuild with KapGen the above charts (first delete the relative tif files from /Img folder if you have alredy built those maps) or download the already built charts set (Upgrade) from the link at the same location.

Let me know. Ciao, Marco.

[Algarve]

Hello everyone,
I'm new here and your work with opencpn has been fantastic, congratulations.
I have a question,
Why the bar of Charts is always yellow, even with zoom is always yellow and the size that comes into the picture?


Is he well configured?


Is there any chance to change the design of the cards?
For example, I sail in an area where there are many islands, and every winter the ground changes with time, so I wanted to change the designs of the islands.

Help me please.
Thanks

[jcjglt]

Because you are in a place in the world where you have only one chart downloaded. Try to go in some place where you have another chart and you shall have a choice or download some free chart as they exist in some US organisations and you shall have a choice.
jcglt

[idpnd]

Originally Posted by Algarve

Is there any chance to change the design of the cards? For example, I sail in an area where there are many islands, and every winter the ground changes with time, so I wanted to change the designs of the islands

The C-MAP charts are absolutely fixed in appearance. You would have to buy updated ones really.

This could be done at home by either a) georeferencing a screenshot of the current map, altering it with an image editor, and reintroducing it as a BSB overlay, which is horribly complicated, or b) simply dropping a few marks within the programme to indicate inacurracies within the charts.

[Totobeloeil]

Originally Posted by Algarve

Why the bar of Charts is always yellow, even with zoom is always yellow and the size that comes into the picture?
Is he well configured?
Is there any chance to change the design of the cards?
For example, I sail in an area where there are many islands, and every winter the ground changes with time, so I wanted to change the designs of the islands.

Your recent CM93 charts and parameters are OK. There is nothing better to be made here.

It won't be easy to find a good recent map for this region.

I believe that even raster charts can't be up-to-date as natural changes frequently happen.

I tried google maps and it seems to be interesting. No depth information of course, but channels can be seen. But is it recent enough ?
Georeferencing sucks ... don't know how to simplify it without extra programmation.

Perhaps you could find best information locally (other navigators or park administration).

Good luck !
Jean-Pascal

[Algarve]

Originally Posted by Totobeloeil

I tried google maps and it seems to be interesting.
Jean-Pascal

Thanks for the response and is very interesting.
By the way, how can I include images in Google Hearth siema OpenCpn?
What is sending data to the GPS, what purpose?
Thank manual techniques of how to do about googleHearth.
Excuse my English.

[Totobeloeil]

Originally Posted by Algarve

By the way, how can I include images in Google earth siema OpenCpn?

With google maps, the first thing I would do would be to make print-screens into bitmaps files for the area of interest.

Next, the problem would be to georeference these image-files. To do that, you need to know geographic coordinates for some points of the image files and enter these "georeferences" into a file.
That is not really easy and there are many causes of possible errors.
So I think it is not a good idea to begin if we don't have means to be sure of the points we are entering (or if we don't know how to verify we did it well).

The points can be entered manually into mapcal_2 (comes with seaclear).
Then some programs (mc2bsbh and nconvert, then tif2bsb) can make bsb / kap files that OpenCPN can read. That last point is easy.

Another difficulty would be to stitch together the print-screens. Possibly it could be made with gdalwarp but I did not try.

The whole procedure would take much time. And I don't believe the Park administration (or maybe the city) don't have something like a plan or a map. It could be cheap.

I don't know how to do with google earth, but it could be a good idea (a KML file ? Maybe you can do it with google maps too ...). Don't know how to make a map from a KML file, but I think it can work.

Jean-Pascal

[Algarve]

Originally Posted by Totobeloeil

That is not really easy and there are many causes of possible errors.

Jean-Pascal

I recognize the reason is on your side.
My technical knowledge is unfortunately small.
I think I'll forget the idea of GoogleEa.

[Algarve]

Originally Posted by Algarve

What is sending data to the GPS, what purpose?

What is, sending data to the GPS, what purpose?

Sorry my bad English.

[Leo12305]

Originally Posted by Algarve

Hello everyone,
I'm new here and your work with opencpn has been fantastic, congratulations.
I have a question,
Why the bar of Charts is always yellow, even with zoom is always yellow and the size that comes into the picture?


Is he well configured?


Is there any chance to change the design of the cards?
For example, I sail in an area where there are many islands, and every winter the ground changes with time, so I wanted to change the designs of the islands.

Help me please.
Thanks

Hey Algarve
perhaps ist there a way if you use charts from OpenSeamap. There you can edit your changes every day if you like.
greeting leo