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Could you please correct the offset in China due to GCJ-02 coordinate?

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Could you please correct the offset in China due to GCJ-02 coordinate? bloodcave 06/04/14 07:03
Version: 7.1.2.2041
OS: Windows 8.1

Hi Engineers from Google,

I think the problem is not strange to you.

The geography information from China usually uses GCJ-02 coordinate system (so called Mars coordinate) as an encryption,
which will cause the coordinate reflected on Google Earth is not so accurate, usually a little offset.

I have give you two examples in the attachment,
one is point data, (Primary Database\Borders and Labels\Labels\Populated Places)
I have manually added placemarks that reflect the real position, so you can see how the offset is.

Another example is the roads (Primary Database\Roads),
you can compare it with the satellite layer.

In fact, I have awared the same problem from maps.google.com, where the satellite view does not coincide with maps view,
while it has been resolved in the Chinese version ditu.google.com.

What I expect is the maps layer (places, roads in this example) adapt theirselves with satellite layer (not the way ditu.google.cn) because we assume the satellite layer is always right and other data may be wrong.

Thanks for your reading.

Re: Could you please correct the offset in China due to GCJ-02 coordinate? Noisette 06/04/14 07:23
Hi, the offset of roads in china is a known issue.  I don't think it's ever been fully explained, just "unknown legal reasons".  As you say, it's correct on https://ditu.google.com/.  You'll find other posts in the Maps forum about this by searching for "ditu".


Otherwise, all you can do is send feedback via the option in the Help menu in Google Earth via "Report a problem" in Google Maps.  Since they are fully aware of the problem, I don't know if it would any good.

Re: Could you please correct the offset in China due to GCJ-02 coordinate? bloodcave 06/04/14 07:42
It seems Google cannot do this fix because the legal restriction, thouth it is not a problem technically.
The way ditu.google.cn do is a progress of "encrypting", but they cannot do an "decrypting".

Google Earth has the most placemarks I had ever seen in (Primary Database\Borders and Labels\Labels\Populated Places), even the small places not displayed on any online maps including Google Maps.
That's why I was expecting this problem resolved eagerly.

Thanks for your answer.