[OSM-talk-nl] [OSM-talk] AND preview for India/China
Martijn van Oosterhout
kleptog at gmail.com
Tue Dec 4 10:04:23 GMT 2007
On Dec 4, 2007 5:07 AM, D Tucny <d at tucny.com> wrote:
> > - Many many placenames, especially in India
> All the placenames in China are in their romanised form, does the data have
> the Chinese names?
I've check the files by visual inspection but no, it appears only
romanised names are available.
> > - Lots of the major regional roads connecting the towns
> For China at least, as mentioned previously, the roads are, at best, very
> very out of date... most expressways (motorways) are missing and the
> accuracy of the other roads is very low... Does the data have any more
> details on roads, such as names or references? That would make it easier to
> try and link them to real data... luckily though, the data is so sparse that
> merging shouldn't be an issue as long as there's a way to work out what
> should be linked where...
Are they wildly off, or do you mean that there's not many points per
kilometre? I don't see any reference, though how do they refer to
their roads, by number, by code, by name???
> > There are also lakes and some rivers.
> The lakes, rivers and included coastline info looks way off, some of it
> might have been the way representing a long long time ago, the PGS data for
> the areas I've looked gives a much more accurate representation of those
> features... Also, at least one lake I've looked at looks very broken, only
> seems to have the south west corner of it's coast with the open ends
> seemingly just joined together to make a small slice of the lake..
The coastlines are not from the AND data. It's using standard mapnik
coastlines for zoom 9, but going all the way down because the normal
coastline data file break horribly at high zoom. I thought I'd fixed
it but apparently not. And I can't use the coastline out of the main
DB 'cause it's not there yet.
I'll see what I can find out about the rivers and such.
> There are only really accent on the romanised forms used in Xinjiang,
> pinyin, the romanisation of mandarin, can have accents to represent tones,
> but these don't seem to be present... I can confirm though that the accents
> on Ürümqi, the capital of Xinjiang look correct, pinyin would be Wulumuqi,
> or with tones, Wūlǔmùqí, chinese would be 乌鲁木齐.
Ok, that's what I wanted to know. I basically assumed the data was in
Latin1, so I wanted a check the it was in the right ballpark. No kanji
anywhere to be found.
> I hope this feedback on the China data is useful... Would be good to see
> some examples of what data is actually in there... As it stands, the place
> info in the GNS data looks more detailed, if there's no more info in these
> files, it would probably be better for me to go back to working on getting
> that data together, I mostly stopped when we heard about the AND data...
> Water features seem to be better covered in the places I've looked by PGS.
> The road data itself seems to be just VMAP0 data...
Well, what I havn't imported yet is:
- There is some coastline data for the pacific ocean, but we already have that
- Administrative boundaries: polygons for provinces I beleive
(examples: Tianjin, Zhejiang, Heilongjiang)
- A file with a list of GPS coordinates with postcodes and names (romanised)
For the boundaries I might try loading them into mapnik direct rather
than via OSM files, see if I can make it work better...
> So, unless there is more data in the files that I'm not seeing on the map,
> we can get the same or better data from other sources with global coverage
> and that the only benefit to this data is that we already have tools to
> convert and import it... Would that be an accurate summary?
Perhaps, at least Mumbai is in the but that's not in China. All the
places names include a population (though I can't guess the quality of
that either). I'd like to provide people access via JOSM so they can
look for themselves, but there's no simple read-only OSM server that I
can just drop in and use. I could write one ofcourse...
Have a nice day,
Martijn van Oosterhout <kleptog at gmail.com> http://svana.org/kleptog/
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