Charts II: NGA - 2700 Charts

[bcn]

Happy,

which range of charts did you go through - just to have an idea who is "plowing" where?

Hubert

[z.stadler]

Originally Posted by recri

My conversions were making column first tables with no gaps in the chart number list to indicate where the plans insert into the list.

But one last try with pdftohtml (from the Ubuntu popplerutils package) has produced a row first table break out, and I've parsed it with minor hassles.

https://docs.google.com/spreadsheet/...JuOXc&hl=en_US
is the new version, I don't have time to look it over this morning.

PDFedit has an alternative converter from pdf to text. It preserves the page layout quite well. With it, and by comparing the results to the list above, I created a more accurate list.

The list is available at
https://docs.google.com/leaf?id=0B-q...hNDRi&hl=en_US

If anyone is interested in the scripts I've written, have a look at
https://docs.google.com/leaf?id=0B-q...zMzQz&hl=en_US

[HappySeagull]

Originally Posted by bcn

Happy,

which range of charts did you go through - just to have an idea who is "plowing" where?

Hubert

...um.Done 6,today was in in 9's..

[recri]

Originally Posted by z.stadler

PDFedit has an alternative converter from pdf to text. It preserves the page layout quite well. With it, and by comparing the results to the list above, I created a more accurate list.

The list is available at
https://docs.google.com/leaf?id=0B-q...hNDRi&hl=en_US

If anyone is interested in the scripts I've written, have a look at
https://docs.google.com/leaf?id=0B-q...zMzQz&hl=en_US

Right you are, looks much better.

[recri]

NGA 2700 chart summary for Sun Oct 09 15:53:54 GMT 2011
processed: 2237 charts
evaluated: 2226 charts
pxhoriz: mean 1.00023 stddev 0.00194
>11*sd: (0.02129) 43081 43083 43062 43101* 43058 43082 43063
>10*sd: (0.01935) 43064*
>8*sd: (0.01548) 43041 43084 43122 43143 43123
>7*sd: (0.01355) 43121 43141 43142 43265 43263* 43161*
>6*sd: (0.01161) 43202 43126 43371 43204
>5*sd: (0.00968) 43225 43264 43343* 43344*
>4*sd: (0.00774) 43287
>3*sd: (0.00581) 43079 54368 54362 54364
pxverti: mean 0.99999 stddev 0.00031
>10*sd: (0.00307) 81563*
>8*sd: (0.00246) 83052* 38502*
>7*sd: (0.00215) 96720 63010 22404* 73032*
>6*sd: (0.00184) 54403 526* 22542* 43343* 73271* 72150* 24511* 91314* 76201*
>5*sd: (0.00154) 96036* 38583* 73470* 623* 23071 24152*
>4*sd: (0.00123) 22549* 43060 91407* 81303* 83218* 81576* 73034*
>3*sd: (0.00092) 71012* 24154* 43064* 91326* 29325* 83039* 91030* 521* 24159* 81729* 23051* 61003* 82025* 92190* 54289* 71400* 24121* 95244 121* 73030 82534* 125* 81145* 73653
pxsquare: mean 1.00000 stddev 0.00024
>11*sd: (0.00264) 73291
>7*sd: (0.00168) 14024
>6*sd: (0.00144) 96720 92370
>5*sd: (0.00120) 92140* 83218* 43204 43062
>4*sd: (0.00096) 14221 38502* 73653 92025* 22544 82384* 91326* 707* 83555* 91096* 81565* 71140*
>3*sd: (0.00072) 61003* 83392* 21161* 91294 91314* 92260 81576* 73008 92520 82025* 92190* 92560* 83020* 96381* 57022* 22532 92030* 81511*
ratio: mean 1.00441 stddev 0.02237
>25*sd: (0.55927) 44285
>13*sd: (0.29082) 38540
>3*sd: (0.06711) 24270
notdone: skipped 1 charts: 22545
notmercator: skipped 10 charts: 17421 18419 43186 43249 43252 43262 43285 56191 71343 76181
-----
Processed all charts with status:
+ 'Rectangular, doable'
+ 'Rectangular, partly doable - rectangular insets'
+ 'Rectangular, partly doable - non-rectangular insets'
+ 'Rectangular, not doable in Phase 1 because of special PLY's needed'
+ 'Chart done, checked and locked'
'processed' is the number of charts processed
'evaluated' is the number of processed charts that didn't get skipped
'pxhoriz' is length(S)/length(N), which should be 1
'pxverti' is length(W)/length(E), which should be 1
'pxsquare' is length(NE-SW)/length(NW-SE), which should be 1
'ratio' is (aspect chart rectangle)/(aspect projected corners),
+ which should be 1
All those 'shoulds' are assuming a rectangular chart area in mercator projection.
'>n*sd' charts are greater than n standard deviations from the mean
'>3*sd' should be 3/1000 of the charts processed
All those 'shoulds' are assuming a normal distribution.
Chart numbers marked with * have been looked at and accepted.
'notdone' are charts with no REF points or no corner coordinates
'notmercator' are charts that aren't mercator, transverse mercator or unknown

[cagney]

recri
43081,43083,43062,43101 and 43064
are all Tmercs

[bcn]

This evening (Europe) we have the nice result of

- no chart "Untouched"
- all charts with "extended corners" screened

Two charts showed up that are still rotated.
And we have right now 136 charts where we need some pixels more to define the corners by the cutouts.

Good progress.

There is still the question how to "release" a chart, declaring it qualified to be used.
Recri's scan is very helpful to get rid quickly of obvious errors but this does not prevent from having to inspect the charts one by one checking against the lat/lon grid.

Perhaps a scheme for chart status of
- first check for release done
- second check for release done/locked
might be an approach.
So release after inspection by two (different) persons.

A howto for inspections and things to look for? What are the parameters to declare a chart "done for release"?

Hubert

[bcn]

Just to have an idea what we are talking about right now for those charts "waiting for release":

- "Rectangular, doable in Phase 1" 1701
- "Rectangular, - With non-rectangular insets" 130
- "Rectangular, - With rectangular insets 287

or in total 2118 charts - not that bad, no?

Hubert

[recri]

Originally Posted by cagney

recri
43081,43083,43062,43101 and 43064
are all Tmercs

Even transverse mercators are supposed to be rectangular charts, no?

I think I'll just throw the 43xxx charts out of the pxhoriz statistics, they were all printed on a crooked press or photographed on a tilted focal plane.

[Joe_Crawford]

Since you are getting close to releasing a few charts, has anyone come up with a naming convention that will support multiple version of the same chart in the same folder/directory (e.g., something like 43081-nn)? I would think this necessary to permit users to easily be able to back up to a previous know version. I also think any naming convention should also be able to support embedded sub-charts with a way of tying them back to the original chart that included them (e.g., something like 43081X-nn where 'X' is an alpha letter fro 'A' to 'Z).

Don't know if this has already been discussed and/or implemented since I'm new here. But, I would assume that what ever convention is used it would also have to be compatible with the other methods currently in use around the world. It might also require unique support within OpenCPN to only load the latest version of a chart if more than one version exists in the folder/directory.

I've only looked at a couple of the charts done so far. But wow, what a great 'find'. And, I'm totally impressed by all the work y'all have applied to making them usable.

[fgd3]

Originally Posted by Joe_Crawford

I also think any naming convention should also be able to support embedded sub-charts with a way of tying them back to the original chart that included them (e.g., something like 43081X-nn where 'X' is an alpha letter fro 'A' to 'Z).

NOAA's raster navigational chart (RNC) files are named with the number of the underlying chart. For example, the RNC of Tampa Bay, Northern Section is based on paper chart 11416. There is a file named 11416.BSB, 11416_1.KAP, 11416_2.KAP, 11416_3.KAP, and 11416_4.KAP. 11416_2.KAP is the Tampa Harbor Inset. 11416_3.KAP is the St. Petersburg Inset. That's a model that seems easy to follow for charts with insets.

Many thanks to everyone who has contributed to this very impressive project. It is a great contribution to the boating community.

Fabbian

[wdkester]

24511 Looks OK to me. The corners are OK the Opencpn grid lines match up and it quilts nicely. It has no projection, but, since the gridlines match up in Opencpn, it iis probably mercator. The shoreline matchup with Google Earth is off in some places by .25NM. Not too good but it is an old chart.

[bcn]

Originally Posted by Joe_Crawford

Since you are getting close to releasing a few charts,

Joe,

probably we will need a little bit of patience still before releasing the first batches of charts.
Neither the quality control "hard points" and procedures, the release process and release cycle (= update of charts), nor the repository and bundling by regions/subregions of the charts are defined.

Perhaps bug reports should be separated from the OpenCPN program bugs and requests. This has not been tackled up to now afaik.

It is still work in progress (with some progress done, yes).

And we will need more contributors. Checking charts and reporting back errors or doubts is very helpful and productive for the project.

Hubert

[nohal]

Hi gang,
we had a little hick-up in interserver communication resulting in the backend not producing charts for the past about 20 hours. Now the batch is running again and will emit all the recently calibrated charts in a while.
I will do the next round on corner images extension when after the generation is done later today.
I'm not very sure how successful will my hunt for free wi-fi signal be along the coast of Albania and Montenegro during the next days, so relax and wait

Take care

Pavel

[bcn]

Hi Pavel,

for sure you will take some of the Adria charts for some quality assurance testing with you!
The developers have to suffer as alpha testers always....

Have fun

Hubert