Showing posts with label SEAiq. Show all posts
Showing posts with label SEAiq. Show all posts

Friday, 15 October 2021

GoogleEarth KAP Library Update

Hi everyone,

It has been years since we updated our KAP Library of GoogleEarth images.  The library provides satellite images translated into 'charts', primarily for use in OpenCPN and SEAiq.  The library is publicly accessible on Dropbox.

The library and its use are described here.

The full set of blog posts relating to the KAP library is here.

Nearly 4000 new KAP charts

The additions and updates to the library include KAP files in the following countries:

  • Africa
    • Tunisia
  • Caribbean
    • Bahamas
    • Turks & Caicos
  • Europe (limited coverage)
    • Ireland
    • Italy
    • Malta
    • Portugal
    • Spain
  • NorthAtlantic
    • Canaries
    • Madeiras
The image below shows the new files in Dropbox.  The Bahamas zip file is large at 2.6GB - it includes about 3600 KAP files.

New zip files on Dropbox

The new files were created using VentureFarther's OpenCPN plugin 'vfkaps'.  The plugin makes it easy to create new KAP files.

Your collection of KAP files is welcome in our library.  Get in touch if you can fill some gaps in our coverage!


Thursday, 23 April 2015

GoogleEarth KAP library for OpenCPN and SEAiq

Hi everyone,
For several years I have been creating and swapping GoogleEarth imagery for use in the free chartplotter OpenCPN.  The imagery is captured using GoogleEarth and GE2KAP while online and produces KAP files for use offline in OpenCPN.  Perfect as an extra aid to navigation in poorly charted areas, as described in my 2012 post here.

All the imagery I have created and which I have collected from others is intended to be shared.  I have shared on an individual basis so far.  The data is now available online.

The library is on Dropbox here.

For those who return to the library looking for new or updated information: click on the "Modified" column heading in Dropbox.  This will sort the files by modification date with most recent at the top.

First download and store somewhere safe the file "_readmefirst.txt".  Keep it for offline use.  The contents of the file are below since it provides much of what I need to explain here.  Please read on!

=======================================================================
                               A Guide to using 
                     Zen Again's Dropbox KAP File Library
                        for use with OpenCPN and SEAiq
======================================================================= 

Origin and Further Distribution
-------------------------------
The KAP files in this library have been generated by various cruisers 
including myself.  All who have provided files to me have indicated their 
willingness for me to distribute them further.  The only proviso we make is 
that they be further freely shared to assist other cruisers.

Intended Applications
---------------------
The KAP files have been tested in OpenCPN and SEAiq using the latest versions
available at the above date.

File Naming
-----------
The ZIP files are named in the following formats:
A. <Region>_<Country>_<Locality>.zip or
B. <Australia>_<State>_<Locality>.zip

File Size
---------
The KAP files are split into modest size ZIP files for two reasons:
1. To allow the selection of specific KAPs of interest without having to 
   download large files.
2. To allow for use in SEAiq which (since it runs on tablets) could be 
   slowed dramatically if many hundreds of KAPs are loaded.

Installation
------------
For those with pre-existing OpenCPN chart folders such as:
  MacOSX:  /user/Shared/charts/opencpn/ge/<region> or 
  Windows: /Users/Public/charts/opencpn/ge/<region> where region is Asia, Indian etc
simply add to (or replace) the existing contents with the contents of the 
ZIP files you download here.

For those with pre-existing SEAiq chart ZIP files simply add my zip files 
nearby and use iTunes to add them to (or later delete them from) SEAiq. 

Using KAP Files
---------------
See the following blog posts:
Using GoogleEarth Imagery for Marine Navigation
  http://yachtzenagain.blogspot.com.au/2012/10/using-googleearth-images-for-marine.html

Making KAP Files
  http://yachtzenagain.blogspot.com.au/2012/04/simple-guide-to-installing-and-using.html

GoogleEarth Imagery on iPad
  http://yachtzenagain.blogspot.com.au/2015/04/cm93-charts-and-googleearth-imagery-on.html

GoogleEarth Imagery on Raspberry Pi
  http://yachtzenagain.blogspot.com.au/2014/10/super-cheap-cruising-chartplotter-and.html

Updates
-------
The library will be updated from time to time.  Individual files may be updated 
so check the date stamp of files you use.  New files may be added so check for 
new files in your region of interest.

Additions
---------
If you would like me to add your images to this library just let me know.

Remember!!!
-----------
GoogleEarth images FADE TO BLACK a few hundred metres from land!!!

=======================================================================

Now to add some help for installing charts in OpenCPN and SEAiq.

Installing and Configuring in OpenCPN
  1. Download all the ZIP files of interest from Dropbox - usually to your downloads folder.
  2. Identify where your existing charts are located (Shown in OpenCPN in Options => Charts => Chart Files.  [I locate my KAP charts in /Users/Public/charts/opencpn/ge on Windows and /Users/Shared/charts/opencpn/ge on Mac OS X]
  3. If they don't already exist, create folders for regions (eg SEAsia, Australia, IndianOcean or similar) in the folder you intend to use for your GE imagery.
  4. Unzip (on Windows use right-mouse-button => Extract To) each of the downloaded ZIP files to the appropriate region folder.  Unzipping will create a folder for the <Locality> described in the readme file above.
  5. Check that your folder structure looks something like "charts/opencpn/ge/Australia/Abrohlos" with .kap files in the Abrohlos folders.
  6. If you wish you can add an extra layer of folders to fully mimic the file naming structure in the readme.  This depends on how you wish to use Chart Groups - read on!
  7. In OpenCPN go to Options => Charts => Chart Files.
  8. You should see a list of chart folders OpenCPN is using, often including a folder "CM93".  If you have some KAP files already loaded then there should be another folder.
  9. Click the Add Directory button, browse to the folder where your new KAP files exist, highlight the folder then click on Open.  I suggest highlighting the region folder (eg Australia, SEAsia etc), not the locality folder (unless you want a Chart Group for each locality).
  10. Tick the "Force Full Database Rebuild" switch and click OK.  OpenCPN will then scan all your chart directories building its chart index database, which may take a minute or three.
  11. When the rebuild finishes, zoom way out (using the "-" key) so you can see the regions covered by your GE imagery.  You should see small red boxes which show the location of each image.  If not go into Options => Display, turn on Show Chart Outlines, click OK and look again.
  12. To view a GE image zoom in over one of the red boxes and centre it in the screen.  At the bottom of the OpenCPN window you should see blue "tabs" appear to the left of the yellow tab which was there before.  The rightmost tab is always the real (vector) chart.  Others are image (raster) charts.  Click on the leftmost tab to open what is usually the best image for the location.
  13. Sometimes OpenCPN zooms when you change from one "tab" to another.  IMHO this is a bug.
Configuring Chart Groups in OpenCPN
  1. Go to Options => Charts => Chart Groups.  In the Chart Groups panel you will see an All Charts tab.  We are going to add more so that the number of GE images OpenCPN is dealing with can be controlled despite them all being installed.  I usually define Chart Groups for a region of the globe (SEAsia, Australia etc).
  2. To create a Chart Group click on New Group and give it a name (for example GEseasia) and click OK.  Then click on your vector charts (often CM93) folder and click Add.  Click on the relevant GE chart folder and click Add.  You may wish to create a Chart Group called CM93only with no GE folders included.
  3. When finished click OK to exit Options.
  4. In OpenCPN zoom way out (using the "-" key) so you can see the regions covered by your GE imagery.  You should see small red boxes which show the location of each image.
  5. Right mouse button, move over to Chart Groups and right into the list of groups.  All Chart Groups is probably ticked.  Click over another group and you should  see a set of red boxes disappear.  Chart Groups are a nice way to manage what images are accessible.  Once familiar with all this you can turn off Show Chart Outlines since drawing them seems to keep OpenCPN quite busy.
Installing and configuring in SEAiq
  1. Download all the ZIP files of interest from Dropbox to the computer you use to sync your iPad - usually to your downloads folder.
  2. Identify where your existing charts are located.  [I locate my KAP charts in /Users/Public/charts/opencpn/zip on Windows and /Users/Shared/charts/opencpn/zip on Mac OS X].
  3. Connect your iPad to the computer and let it sync if it wishes.  Open iTunes if it doesn't open automatically.
  4. Click on the iPad symbol at top left of iTunes, then click on Apps on the left.
  5. Scroll all the way down past the Apps list to the File Sharing list.
  6. Click on SEAiq Open in the File Sharing list on the left.
  7. On the right you now have a SEAiq Open Documents list which may be empty.  At the bottom of the list click on Add.  Browse to the folder containing the downloaded ZIP files.  Select those you wish to install in SEAiq and click Add.  You will see a progress bar at the top of iTunes.
  8. On the iPad open SEAiq and click on Charts at bottom right.  Wait for it - the response can take a few seconds if you downloaded ZIP files containing hundreds of images.
  9. When the Charts page loads you should see a row for each ZIP file, with each showing its size and number of KAP (image) files it contains.
  10. Now you see the logic behind the file naming scheme!
  11. Note that you download CM93 charts in a similar way, just select your CM93 ZIP file in iTunes and Add it to SEAiq.
  12. Click on Navigate and pan/zoom to the locality of the imagery you transferred.  You should see faint orange boxes delimiting the images.
  13. To change between vector (CM93) and raster (KAP image) charts click on the Settings tab and and move the slider on the Raster line in the Charts section, then return to Navigate.  You may need to pan slightly to have the page redraw.  Hey Presto!
  14. ZIP files can be removed from SEAiq in either iTunes or on the iPad directly in the Charts page. 
Hope the above helps you install the imagery.  Let me know if you like it and if you want more.

Here are two screenshots from SEAiq showing Cape Vlamingh on Rottnest Island WA.  Breaks on the reefs are clearly visible.
GE image of Cape Vlamingh, Rottnest Island, WA in SEAiq
Chart (decluttered) of Cape Vlamingh, Rottnest Island, WA in SEAiq

Wednesday, 15 April 2015

CM93 Charts and GoogleEarth Imagery on iPad

Hi everyone,

!!! NOTE !!!
From SEAiq version 4.0 (released December 2015) CM93 charts are no longer supported.

On Zen Again we have been using CM93 vector charts and KAP raster "charts" (produced from GoogleEarth imagery using GE2KAP) in OpenCPN as an aid to navigation.  See our blog from 2012 on the latter.  Ever since then we have been under the impression there was no software to present this information on our iPads.  During our cruise through SE Asia we found no-one who knew of such software.

Today we discovered we were all wrong!  Thanks Carolyn for pointing us in the right direction.  There _is_ an app which can display CM93 and KAP charts on iPad.  SEAiq is the answer and it is brilliant.

Within minutes of downloading and installing the app I had installed our CM93 charts.  A few minutes later I had a few KAP files installed too.  Once aboard Zen Again it took only a few minutes to configure SEAiq to accept AIS, GPS and instrument data from our Vesper XB-8000 AIS over WiFi.

The two screenshots below show example KAP and CM93 views, both of Direction Island in the Cocos-Keeling Islands.  Changing between the two involves switching one setting (Raster Charts On/Off).

KAP file GE image of Direction Island (Cocos-Keeling)
CM93 chart of Direction Island (Cocos-Keeling)
The two screenshots show the presentation of CM93 charts in Fremantle with WiFi data enabled.  The Status Bar the top of the screen is now populated, Zen Again is the black ball and AIS targets are shown.
Fremantle
Success and Fishing Boat Harbours close up
Here's another view with CM93 chart detail set to "Basic".  This reduces clutter to make AIS targets clearer.
Simplified CM93 View of Fremantle and Gage Roads
SEAiq has a good table view of AIS targets.  The information page for each target is very detailed.

AIS Targets Page
Individual AIS Target Page
SEAiq also supports email requests for and display of GRIB files.  It will generate an email request to send to SailDocs.  It would be nice to see the range of GRIB providers expanded.

Weather Page
SailDocs GRIB Request Email
I later loaded a set of several hundred KAP files.  This wasn't as straight-forward as I had hoped but I eventually got them all installed and working.  I used iTunes to transfer both CM93 and KAP files.

The two issues I have found so far are:
  • Some zip files containing kap files are not accepted by SEAiq, despite successfully loading the same set of files individually
  • Unsurprisingly SEAiq gets a little slow if a large set of KAP files is loaded
Update (20 April):  The zip issue has been identified by SEAiq as the presence of Mac OS X hidden files in zip files.  These files have names like __MACOSX and .DS_Store and can be searched for in zip files using the command [unzip -l <filename>] (without the square brackets).  If such files are found use the command [zip -d "__MACOSX*" "*.DS_Store*”] to remove them from the zip file.  The next release of SEAiq will ignore these files.

It is surprising that SEAiq is not listed when one searches for "marine navigation" in the App Store.  I think that explains why we've never heard of it before.  I have mentioned this to the SEAiq folks.

Update (20 April):  SEAiq will be listed under "marine navigation" from its next release in the App Store.

One thing's for sure - SEAiq is a very useful iPad app for sailors who need their charts supplemented by GoogleEarth imagery.  It is a very nice chartplotter generally, but the support for both CM93 and KAP charts sets it apart.  Very cool.