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Every map of China is wrong

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Re: Every map of China is wrong

#61

Post by Reason077 »

shikon7 wrote: post #57
relaxing wrote: post #48

Earlier quoted context omitted.

I want to know why Google hasn’t corrected their map overlays. The shift in the roads makes it frustrating to look at.

Because Chinese law forbids to convert their coordinates to WGS84, and using the Chinese coordinates for satellite data would give a discontinuity at the border. This is explained in the article.

Discontinuity at the border isn't a big issue compared to all locations in the country being wrong relative to the satellite view.

If Google cared enough, I'm sure they could find a solution - since Google doesn't operate in China, they don't really have to respect Chinese laws. But Google doesn't operate in China so they don't care that much and are presumably happy to leave things the way they are.

Also, keeping things the way they are keeps drawing attention to the issue, which is probably better than to try and cover it up.

Re: Every map of China is wrong

#62

Post by hinkley »

exmadscientist wrote: post #56
hinkley wrote: post #50

I remember a couple of years ago someone was claiming the Three Gorges Dam was buckling and about to fail, based on the satellite views showing the top of the dam weaving back and forth. Everyone sane thought it was some interpolation bug from Google trying and failing to tile the pictures properly, but maybe this is the reason why.

It probably doesn't help that reliable sources tell me that the Three Gorges Dam is, in fact, absolutely goddamn crooked and janky. One reason they don't allow close photography of it is simply that it looks so very bad. Grand Coulee Dam, on the other hand, despite being decades older? It's dead-on level .

[flagged]

Re: Every map of China is wrong

#63

Post by bee_rider »

javajosh wrote: post #30
Intralexical wrote: post #18

Earlier quoted context omitted.

The consequences for them seem a bit more urgent, though, given Seoul lying in artillery range of the DMZ.

Yes, I'm sure obfuscating Google Street maps will prevent DPR artillery from accurately striking targets in Seoul.

On one hand, I’m quite sure South Korea’s government has put a whole lot more thought into this than we have, and they decided to obfuscate the maps so… who knows, I guess they decided it helps.

On the other hand, given that NK is using, what, WW2 vintage artillery, I can’t see how. They are probably aiming “south” with magnitude “lots,” right? What good is a 500 meter offset, or whatever, going to do when they are just aiming at the city in general.

Re: Every map of China is wrong

#64

Post by greatgib »

Would a GPS navigation app still work when working with gcj-02 data? Regarding the fact that every street and landmark will be distorted . Something like the itinerary of Google map for a trip?

Re: Every map of China is wrong

#65

Post by obscurette »

sib wrote: post #54
lolc wrote: post #13

Earlier quoted context omitted.

Thanks for the details. It is always interesting how the most innocent things are seen as danger by an autocracy.

For many years, the most accurate (paper) maps of the Soviet Union were those created by the CIA. The USSR's own maps included lots of intentionally incorrect data.

I remember from my childhood (early seventies is Soviet Union) that it was allowed to print road maps with straight lines only and distances between cities were always at least several kilometers wrong. I also remember when my classmate lost the map when orienteering (these were relatively accurate) and he and his parents had a lot of trouble because of that.

Re: Every map of China is wrong

#66

Post by hwbunny »

N19PEDL2 wrote: post #12
lolc wrote: post #6

So Openstreetmap must be illegal in China! And indeed it is: https://wiki.openstreetmap.org/wiki/China Of course that doesn't stop people from mapping every bench in China https://www.openstreetmap.org/search?query=China#map=3/33.99...

It seems that even taking geotagged photos is illegal in China, indeed some camera models automatically disable geotagging when inside China: https://ogleearth.com/2012/05/why-do-panasonic-leica-fujifil...

Never had any issues. Noone cared about my camera while I was there. And I created like 5K photos there. Not that I ever use GPS, because it eats away your batter, but noone really cared about it.

Re: Every map of China is wrong

#67

Post by ammo1662 »

cat_plus_plus wrote: post #60

I am not a fan of China, but not wanting coordinates of strategic targets in your country to be precisely known doesn't seem crazy. Other restrictions they have like not being able to access the Internet, or being put in reeducation camps, or not having a say in how your government is run would affect me badly. But if navigation in my car worked fine, would I care if topography is a bit distorted? During the pandemic…

Topography in the navigation app will not be distorted for Amap or Baidu map. They looks correct.

Maybe people just don't know how important a navigation app is. With enough usage data, you can know the traffic status of any area. Amap and Baidu already use these data to provide the countdown of traffic light. It has 90% accuracy. You can also have a deep understanding of the economic status, or find out some hidden buildings.

So for an algorithm which is already reverse engineered many years ago, it cannot protect anything. It is just a policy to stop foreign companies to join this game.

As for the reason, "national security", "unacceptable risk".

Re: Every map of China is wrong

#68

Post by kccqzy »

keepamovin wrote: post #43

Here’s where it gets interesting — GCJ-02 is based on WGS-84, but with a deliberate obfuscation algorithm applied to it. The effect of this is that there are random offsets added to both latitude and longitude, ranging from as little as 50m to as much as 500m. Holy shit. I can't believe they created an adversarial mapping standard. That is insane. It really paints a picture of their worldview I think. The oppressed "…

> Wow, what it must be like to have that view that everyone else is against you

This is true. Anti-Chinese sentiment right now is high worldwide. And had been high since the 19th century. Look up Chinese Exclusion Act.

Re: Every map of China is wrong

#69

Post by CMCDragonkai »

keepamovin wrote: post #43

Here’s where it gets interesting — GCJ-02 is based on WGS-84, but with a deliberate obfuscation algorithm applied to it. The effect of this is that there are random offsets added to both latitude and longitude, ranging from as little as 50m to as much as 500m. Holy shit. I can't believe they created an adversarial mapping standard. That is insane. It really paints a picture of their worldview I think. The oppressed "…

I believe this is due to communist forces being under siege since the beginning of the ideology.

https://en.m.wikipedia.org/wiki/Siege_mentality

See how other nations dealt with the Russian revolution, and subsequently.

From CCP's perspective it has been surrounded by enemies from even before the founding of the PRC.

Remember violence begets violence.

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