OpenCpn charts available for purchase

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GHA

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Since OpenCPN is, well, open, does this leave offer the possibility for some bright spark to add some code and write the charts out again in an unrestricted/unencrypted format? The same goes for the UKHP charts available through VistMyHarbour.
 
JumbleDuck said:
Since OpenCPN is, well, open, does this leave offer the possibility for some bright spark to add some code and write the charts out again in an unrestricted/unencrypted format? The same goes for the UKHP charts available through VistMyHarbour.
Click to expand...
I think they had to jump through some very complex hoops of fire to be allowed to do this, the plug in seems to be in 2 parts..
http://opencpn.org/ocpn/book/export/html/38


The S63 charts are working with the latest 3.3 beta release, and all S63 chart worldwide, are available for purchase. The support is through a two part plugin, one part open source and the other part closed. The encryption and the commercial aspect is handled by a separate entity, o-charts.org
 
GHA said:
I think they had to jump through some very complex hoops of fire to be allowed to do this, the plug in seems to be in 2 parts..
http://opencpn.org/ocpn/book/export/html/38


The S63 charts are working with the latest 3.3 beta release, and all S63 chart worldwide, are available for purchase. The support is through a two part plugin, one part open source and the other part closed. The encryption and the commercial aspect is handled by a separate entity, o-charts.org
Click to expand...

Something similar happens with the VMH UKHO charts, which come on an encrypted stick. However, once the chart information is in OpenCPN, what's to stop it writing it out again?
 
JumbleDuck said:
Since OpenCPN is, well, open, does this leave offer the possibility for some bright spark to add some code and write the charts out again in an unrestricted/unencrypted format? The same goes for the UKHP charts available through VistMyHarbour.
Click to expand...
Mugging old ladies is easier and more profitable than thieving charts from the rightful holders of the copyright.
 
GHA said:
No idea how it all works, but certainly doesn't look trivial..

http://www.cruisersforum.com/forums/f134/s-63-plug-in-for-opencpn-112672.html#post1404539
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MM. Interesting. It looks as if they use, or have to use, a binary blob to decrypt straight to screen, so that OpenCPN never "knows" what it's displaying, just the areas to be displayed. Well, that certainly doesn't rule out all the options, but it certainly makes it harder.

elton said:
Mugging old ladies is easier and more profitable than thieving charts from the rightful holders of the copyright.
Click to expand...

Your concern for my immortal soul is appreciated. What I'd really like to be able to do is use UKHO charts with OpenCPN under Linux, and I'd be more than happy to pay the £30 that Windows users can pay to do so. As many, many publishers have found over the years, over stringent DRM is not necessarily a good business model.
 
From Wikipedia

S-63 is an International Hydrographic Organization (IHO) standard for encrypting, securing and compressing electronic navigational chart (ENC) data.
The Data Protection Scheme was prepared by the IHO Data Protection Scheme Advisory Group, and was based on the protection scheme developed and operated by Primar as part of providing their protected ENC service. ECC (Electronic Chart Centre) and United Kingdom Hydrographic Office were the original contributing organizations.[1] The UKHO has since left this arrangement and Primar is now operated exclusively by ECC.
The standard was adopted as the official IHO standard by the IHO member states in December 2002.[2]
The S-63 standard secures data by encrypting the basic transfer database using the Blowfish algorithm, SHA-1-hashing the data based on a random key and adding a CRC32 check. The standard also defines the systems to develop permit files that are delivered to end-users of ENC data enabling them to decrypt the data and use it for navigation.[1] It also defines the use of DSA format signatures to authenticate the data originator, however because of poor implementation of the standard by ECDIS hardware manufacturers, virtually all signing is performed centrally by the IHO which acts as the scheme administrator. Exceptions to this are a few smaller resellers such as AUSRenc operated by AHS.
Compression is achieved by applying the standard ZIP (file format) algorithm to the base and update ENC files, before encryption. The other files are not compressed.
 
elton said:
Mugging old ladies is easier and more profitable than thieving charts from the rightful holders of the copyright.
Click to expand...

Fun provides more motivation than money in some cases. I remember writing code to crack encrypted software in my youth. Just a matter of some interrupt driven machine code to grab chunks of code just as they were unscrambled but not executed. I did play the game afterwards but getting around the copy protection was about as much fun as playing the game.

I also remember a sales guy demonstrating some software at a developer convention. He boasted that it required a hardware dongle and couldn't be cracked. Then he made the mistake of leaving it over lunch to allow developers to play with the software. Severely pi**ed after lunch when his demo machine was running the software without the dongle.

This was about 30 years ago and things have become hugely more complex since. The difficulty level will have increased, but someone may just decide that only increases the fun getting around it even though it will be fiendishly difficult to hack. However, it's not that likely as it's a niche item and won't have appeal of hacking something with broader appeal.
 
Assuming it all works then everyone can get a fine piece of opensource software working in Europe without being stuck with aging cm93 charts.

But how much are the charts......
 
So 15 or so Euro's for the S63 permit, and then between 15 and 22 Euro's per chart... which seems expensive when I can download MX Mariner with charts for the entire south coast for less than £10..???
 
Fantasie 19 said:
So 15 or so Euro's for the S63 permit, and then between 15 and 22 Euro's per chart... which seems expensive when I can download MX Mariner with charts for the entire south coast for less than £10..???
Click to expand...

And also for Windows users at least uk charts for opencpn are available from visitmyharbour for about £50, so there is no issue.

I think maybe the issue is for people who want to use linux as i think the vmh ones are windows only.
 
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