Random Noise

Generating Contour Line from Aster GDEM

Generating Contour Line from Aster GDEM dem files can be very easy if you know the right tools to use.

Aster GDEM GeoTif DEMs covers 1 degree square and it is at present the most detailed DEM you can download from the internet. The problem I had was that I wanted the contour for only a small area, and when I tried editing the GeoTif file in any image editing software, the Geo reference were discarded. But eventually I found a solution in GDAL, a command line tool. I used GDAL to crop the GeoTif file without losing the Geo-references.

Using the cropped Geotif, I then use AutoCad Map and Dem2Topo to generate contour at 1m interval! And the result I got was quite okay considering the facts that there is no topographical data available elsewhere.

If anyone wants a detailed step by step help, please leave a comment, and I will post the steps with all the links and command options. Thanks.

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Making High Resolution Large Google Earth Maps

Here is a simple solution if you want to capture large high resolution googles satellite imageries from Google Maps. Follow the steps I’ve outline below:

Open Google Maps and go to the location for which you want to capture the images. Select the type of maps. (Street map, Terrain, Satellite or Hybrids)
Select an approximate center of the area you want to capture and zoom in to the desired level. (The max zoom level is 20, but 19 is my recommendation as I saw no difference between the two level.) And the higher the zoomed in level, the larger your files will be.
Click on the Link button (near the top left side) and copy the code for “Paste HTML to embed in website”.

Open Notepad or any text editor and Paste the copied codes into it. Now you need to add and modify the HTML codes.
<html> <head>My Custom Maps</head> <body> <!-Code from Google Map goes here --> <iframe width="425" height="350" frameborder="0" scrolling="no" marginheight="0" marginwidth="0" src="http://maps.google.com/?ie=UTF8&ll=37.0625,-95.677068&spn=48.822589,93.076172&z=19&output=embed"></iframe><br /><small><a href="http://maps.google.com/?ie=UTF8&ll=37.0625,-95.677068&spn=48.822589,93.076172&z=4&source=embed" style="color:#0000FF;text-align:left">View Larger Map</a></small> </body> </html>
In the code above modify the above width and height (in bold). It will be the size of the map you want to capture. For reference at zoom level of 19, to capture a size of around 1 Sq. Km. the width/height of 8000 did just fine but it will differ from location to location.
Note: The text in italics is your location’s Longitude/Latitude coordinates and you do not need to modify it.
Save the file with a .htm or .html extension on your PC. Open that file with your browser. (I recommend Firefox or Google Chrome, as it always works)
Wait for the Map to finish loading on your browser. Depending on the size of your location, details/level of zoom and your connection speed, it might take from a few minutes to hours.
After your map is loaded Save the page and do not forget to Select the Web page, Complete Option while saving it.
When you save the map, the browser will have saved a bunch of image file, and depending on the size of your map, it might be a few hundreds to thousands of images/tile files. Manually stitching all this images will take days so, I have a better way.
If your maps are smaller than 5000 x 5000:
Download and install these extensions/addons for your browser:
For Google Chrome. > ScreenGrab or Screen Capture
For Firefox > ScreenGrab or Screen Capture EliteLoad your maps and save it using the addons above.

However for maps larger than 5000x5000,
Download and install FastStone Capture (or select a direct link Installer, Zipped or Portable version)
Now load the maps you saved in step 7 in your browser and launch the FastStone Capture and select the Capture Scrolling Windows option/button to capture the maps.

Be happy now!

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Is Bin Laden really dead?

Or is the US claim of killing Bin Laden some kind of a conspiracy? With the US not releasing any kind of proof to prove that Bin Laden is really dead, the skeptics are finding it really hard to believe that Bin Laden is really dead.

The US is not telling the complete truth about Bin Laden’s death. Something is going on that they are not telling us. We know that Bin Laden and his association with the US in the past. Or is the American Government holding Bin Laden in its custody, and claiming that he is dead fearing reprisal from the Al Queda. Or is it that the US knew that Bin Laden is dead having died naturally, and to make its fight against terrorism a little dramatic claiming to have killed Laden? And maybe that is why they are not able to give any proof.

But the thing is, we do not care if the US killed Laden or he died from constipation, we just want him dead. Period.