How to download

Some problems when downloading

Options to set

How to view downloaded maps

How to combine small images into one big image

How to know the longitude and latitude of each image

How to download?

See the screenshot. It is very easy to use.

Firstly, enter a project name, such like "Mytask.gmid". All project files are saved as *.gmid. If you want to continue a old project, click button "Open project".

There are 4 parameters (Left Longitude, Right Longitude, Top Latitude, Bottom Latitude) to define the area scope of images that you want to download.

The zoom parameter define the image precision.

Select a path to save the project and downloaded images, then click button "Download", OK, start downloading now ... !

When downloading, the log window will display the downloading process. When finished, the log will be saved to a file.

Parameters explainment:

1. Left Longitude: -180<value<180, for East, the value is positive, for West, the value is negative.
2. Right Longitude:-180<value<180, for East, the value is positive, for West, the value is negative.
3. Top Latitude:-85<value<85,for North, the value is positive,for South, the value is negative.
4. Bottom Latitude:-85<value<85,for North, the value is positive,for South, the value is negative.
5. Zoom: defines the image precision, the max zoom is 19. (For trial version, the max zoom is 13)

The followed sketch map explains the area scope:

For longitude and latitude, the input measurement is degree. You can convert the measurement of "Degrees, Minutes,Seconds" to "Degrees" by click menu
"Tools->Convert 'Degrees,Minutes,Seconds' to 'Degrees'...".

How to get the lat/long information from Google Maps?
You can right-click a location on the map and select "What's here?" The coordinates of that location will automatically appear in the Search box at the top of the page.

How to re-download failed files?
When downloading, if some files failed to download, you can re-download them by click menu "Tools"->"Re-download failed files".

Some problems:

1. Google map uses a protection mechanism to keep a good quality of service. If one makes too much requests, google map will add its IP address to a blacklist, and you may see a message:

Google Error : 403 forbidden

If this happend, Satellite Maps Downloader will show a messge in log window: May be your IP is banned by Google. Then you must wait for some time or change to another IP.

2. For some area, there are not high precision images on google's server, so may be caused a error when you try to download such images. If this happend, you need to set smaller zoom size to download. (For most areas, the max zoom level is 18)


 Options to set

Here you can set some parameters and proxy server. The 'Sleep' parameter means the interval time between two requests of each thread, try to avoid ip being banned.


 How to view downloaded satellite images?

You can view downloaded maps without combining them into one big BMP.
We provide a tool to viewer the images, you can run it from menu "Tools"->"Satellite Images Viewer".

Then open a project from menu "File"->"Open project..." to view the map.


 

How to combine small images into one big image?


After downloading, all small images are saved on your disk. Then you can combine them into one big image map.

We provide a tool : Combine.exe. You can run it from menu "Tools"->"Combine images... ".


The output big image is in BMP format. You can convert it to other format by yourself using some image tools such like PhotoShop.
And it will create a World File: *.bmpw, this is a text file, you can use the bmpw file to help to import the image into some GIS softwares.

 How to know the longitude and latitude of each image

There are two methods to know the longitude and latitude of every downloaded image.

1. After downloading, the software will create a text file named as "projectname_list.txt" in your project path. In this file all the images' longigude and latitude information are saved.

The file looks like:

ImageFileName Left_Edge_Longitude Right_Edge_Longitude Top_Edge_Latitude Bottom_Edge_Latitude
gs_132775_90192_18.jpg: 2.33871459960938 2.34008789062500 48.85025819596752 48.84935452221043
gs_132775_90191_18.jpg: 2.33871459960938 2.34008789062500 48.85116185341521 48.85025819596752
gs_132775_90190_18.jpg: 2.33871459960938 2.34008789062500 48.85206549455355 48.85116185341521
gs_132775_90189_18.jpg: 2.33871459960938 2.34008789062500 48.85296911938262 48.85206549455355
gs_132775_90188_18.jpg: 2.33871459960938 2.34008789062500 48.85387272790248 48.85296911938262
gs_132775_90187_18.jpg: 2.33871459960938 2.34008789062500 48.85477632011322 48.85387272790248



2. When you view map in Satellite Viewer, the longitude and latitude will be displayed in the statusbar.

And in the log file, the exactly longitude and latitude of the downloaded area are saved as Left Longitude download.., etc.. see the followed example.

An example of log file:

Project: C:\Downloads\paris_18.gmid
Log begin...
Now time is:2012-7-22 22:31:27

Left Longitude input= 2.34
Right Longitude input= 2.35
Top Latitude input= 48.86
Bottom Latitude input= 48.85

X1 = 132775
Y1 = 171951
Y1=90181
Y2=90192

Left Longitude download=2.33871459960938
Right Longitude download=2.35107421875
Top Latitude download=48.8601975308897
Bottom Latitude download=48.8493545222104

All images' scope information are saved to C:\Downloads\paris_18_list.txt

Total count of images would be downloaded: 108

Download threads count: 8

Zoom level: 18

path: C:\Downloads\

FileNameFormat=1

Start downloading...
--------------------------------
Thread1:seq=4, file=gs_132775_90189_18.jpg ->ok!
Thread4:seq=3, file=gs_132775_90190_18.jpg ->ok!
Thread2:seq=1, file=gs_132775_90192_18.jpg ->ok!
Thread3:seq=2, file=gs_132775_90191_18.jpg ->ok!
......