OpenCPN Survey Plugin Depths and VentureFarther

[jonturgeon]

This sparked a bit of interest,cool. I just released a new version that also allows the output of the VDR (Voyage Data Recorder) to be uploaded. So NMEA recorded files are now usable. Started to look at building a NMEA Android recorder. Seems that might give users who don't use OpenCPN a chance to contribute.

Why MySQL, well I have been at this site for just under 3 years now (we are currently doing a circumnavigation). When i started I had a lot of background in Java development but was new to GIS. Also with MySQL 5.7 I am getting done what I need to do.

I had also been told of TeamServ, but i could not see how to get info out. Probably my misunderstanding of how it works and given that I usually have limited internet I did not dig too deep. I also plan on spending some time with data QA if the amount of data grows. Since I am a single developer I need to chose carefully what I can work on.

As a reminder, I am not trying to replace official government charts. I am trying to give active cruisers that go to out of the way, poorly charted areas at least some idea as to what to expect. This is crowed sourced data so use it with caution. Of course all cruising guides and official charts also carry that warning...

About MapBox, I contacted support about what I hope to accomplish. I was put in contact with a developer there. That was about 2 months ago and I had several back and forth emails. Now that I have an upload/display working I'll re-establish contact to try and move forward with them. This would allow anyone to display a depth layer on any map. Then I will integrate with the kap file create.

Navionics is great, did I look at the crowd source depths. Not really since, although I have Navionics, I like something a bit more open to others that don't.

About trying to register, sorry about that. Look on the site for the contact me info and shoot me an email about what you tried. I'll make sure you get setup. A one man development/testing/support team is a bit challenging

[bcn]

Originally Posted by jonturgeon

About MapBox, I contacted support about what I hope to accomplish. I was put in contact with a developer there. That was about 2 months ago and I had several back and forth emails. Now that I have an upload/display working I'll re-establish contact to try and move forward with them.

Would you mind to ask about mbTiles and vector charts then?

This would allow anyone to display a depth layer on any map. Then I will integrate with the kap file create.

Issue is that a BSB3/.kap file does not allow for transparency.
Starting with a png with transparency does not result in a TIFF with alpha channel.
At least not using imgkap..

And as far as I know OCPN is not prepared for transparent raster on the canvas. Or a layer with transparency. Something that might change though.

[seandepagnier]

I still haven't heard about methods for converting mbtiles to kap.

In any case, I intend to support mbtiles natively by opencpn as a chart format, and mapproxy can easily generate mbtiles charts for example, using cm93 chart cell coordinates to build google imagery charts.

I am waiting for the general s57 refactor to reduce conflicts. Raster charts with transparency create a problem with properly quilting the charts. I am not sure how to solve correctly. There are a few possible ideas I can try.

[jonturgeon]

I am starting to rethink this with vector tiles. I started to implement and when slowly figuring out the process it looks like I would need to re-publish all the tiles every time a survey is uploaded. Seems a bit too heavy for what I am trying to do. I have another idea as to how to ad the depths to kaps though which fortunately is simpler and would not require the full rebuild each time.

Sean, how would the average user be able to select and download these mbtiles? Which satellite provider would they be able to use (from what I see either Google or Nokia are really by far the best)?

[seandepagnier]

Many wms or tms servers will do for data.

As far as adding user depth to kap... not really good because of loss of data.

Why not add the depth to the mbtiles via a tag rather than in the actual raster data? Opencpn then renders the tags after drawing the tile. mbtiles already supports this and it allows for corrections etc without losing imagery data.

[jonturgeon]

About loss of data, there will always be that since the recording of depths happens so often that to display all of them would make it unreadable. I have a primitive filter that I am using now to pick the significant depths. I will need to work more on this when/if more than one survey happens for a given area.

One thing with VentureFarther, although we use OpenCPN a lot of my users do not. What I end up doing has to work for them also. Not sure how many other nav programs support mbTiles. I do know this though, unless made very easy, the average cruiser will not use them. Sort of why I started web based kap creation. Any plans to connect OpenCPN to the web to download these tiles? I worked with the developer of SeaIQ (iPad nav app) to make a web service call to VF (open to OpenCPN if someone wants to build a plugin) to generated and download a kap. Just double tap on the chart where you want a sat kap and it does the rest.

My original idea was to use tags with mbTiles. I had planned on using MapBox's upload api to be the online repository for these (I really don't want to host another server). They also create the tilesets from the upload (which can be geojson which I am already doing). You can also create the mbtiles yourself. From the api you can not delete a tileset (without using mapboox studio) only create new or overlay the original. These limitations stated to raise concerns. Now, I am no expert in this, still learning. So if someone knows something different please jump in.

[jonturgeon]

Hey all, thought I would see if anyone here has a better idea as to how to add the soundings to a KAP. I started down the route of adding the soundings as graphics. Possible but running into some issues. So, to make sure I do not spend too much time doing this when there is a better way I thought I would ask. First, does anyone know if it is possible to embed the sounding info in the header of the kap and have it then displayed? Any other ideas or possibly a better way? One limitation though, I really do not have the resources or the time to host another server, so the solution would have to work within the current KAP create (it is roughly like the other KAP create software, but written in Java, so any Java libraries could be used).

[bcn]

.kap (or BSB) files are just raster - the header does contain the meta data (the doucmentation in the manual you have seen for sure), but no content.

So what you can do going raster is creating a .kap (with transparent background, something not foreseen in BSB AFAIK; or white) for overlays in OpenCPN or any other program that is able to display .kap files.
In the case of OCPN waiting then, that overlays with transparency are getting implemented.

Or - more unexplored territory - create a very basic S-57 vector chart that just contains your soundings. Transparent S-57 layers are an even more unknown terrain ....

[rgleason]

So what you can do going raster is creating a .kap (with transparent background, something not foreseen in BSB AFAIK; or white) for overlays in OpenCPN or any other program that is able to display .kap files.
In the case of OCPN waiting then, that overlays with transparency are getting implemented.

Magical Kap transparency in Opencpn would also help with Weatherfax!

For a beta version of survey_pi.dll Mike Rasbats may have one in his repository, but
OpenCPN Beta File Thingie Login rguser rgpass
has one too under 4.2.1+ PI Win
compressed file 3-20-16

See this for Opencpn display of Weatherfax Kap files.
http://www.cruisersforum.com/forums/...ml#post2186583

[jonturgeon]

What I would call the alpha version of kaps with soundings has been released. It is not well publicized (on purpose) on the site as being available in order to minimize the use until any issues that arise have been corrected. If you go to VentureFarther (if you do not have a VentureFarther id you will need to create one before clicking the link). On the "Chart Generation" page, click the upper right hand corner "map control', select the "Soundings" layer. This uses Ajax to get the soundings and draw them on the map, so depending on your connection speed you might have to wait just a few seconds(I need to add an Ajax indicator). Then just click the "Generate Chart" button. The kap will have the soundings and the track line (given that these will never be a complete survey the track line is drawn) superimposed on the sat image.

[seandepagnier]

Originally Posted by jonturgeon

What I would call the alpha version of kaps with soundings has been released.

Is it is feasible to implement a plugin which requests a kap of the current viewport, downloads it, and displays it automatically?


Also, I think you know as well that jpg in mbtiles is superior for satellite imagery for file size. For this reason, it may make logical sense to transmit the kap header and jpg image over the network in this case, and the plugin can from this produce a kap file.

[jonturgeon]

Sent an email with the details of what a plugin would need to do to get the kap. Given all that I have still left to do with VentureFarther I really do not have any time to build one, so if anyone else is interested just let me know.

Not sure how much smaller the jpg would be. I track the size when the kaps are created and given that the colors are 256 (sat images) not 127(kap image) I don't think size would change much. What would happen though is probably a better resolution if OpenCPN could view the 256 color image.

[rgleason]

I was curious about this topic. Has anything else happened?

[ealltech]

After many requests I failed to get any of my data exported back from TeamSurv, although several tracks were submitted. I wanted to use that data for development work. At one point I did a 'bar check' to validate my data and submitted my findings but the processed data visible on the TeamSurv website was not updated to reflect this check. A black hole.

[jonturgeon]

Jon, the developer of https://www.venturefarther.com (VF) here. Sorry, but I have not heard from any plugin developer who might be interested in integrating the KAP request from VF into an OpenCPN plugin. I, unfortunately do not have the time given the amount I am putting into the VF website (I need to cruise sometime ;-) ). If there are any bored plugin developers out there, the offer is still open to provide the API to VF for web based KAP creation (I would love it as I am an active OpenCPN user). You can still request/create KAPs online on VF, save them to a local folder and rebuild the chart index in OpenCPN manually (which is how I use it). A bit more time consuming than when I use SEAiq (which integrates VF's API for KAP creation), which just requires panning to the area you want a sat KAP, double tap, wait a few seconds and it is downloaded/added automatically. I am releasing an update (depth upload and immediate sharing are already available with KAP depth overlay) to the NMEA upload soon, it will digest a lot more of the incoming NMEA data (recorded by the OpenCPN VDR plugin). If adopted, it could prove to be pretty cool with several new features around online sharing of cruising info. Any one interested doing a few VDR recordings and sending (or uploading using the current depth upload) them to me to do some pre-release testing just let me know (or also once it is released to give the upload a whirl).