Working with COG in GDAL

Question

I have worked with GDAL previously and USGS 1/9th arc second data many years ago before I became severely ill and had to give it up. I am now looking at resurrecting what I was doing.

The problem is that since I had been using GDAL things seemed to have changed A LOT, and I am now completely lost as to how to do what I want.

What I need is to be able to download a block of 1m DEM data as a GeoTiff to my local HD for processing, once I have that I should be able to pick up from where I left off and convert it to a 16 bit normalized Height map for importing into the game engine after ensuring there are no NaN values and ranging the data to have a minimum value > 2.

At this point though I don't even know how to get the GeoTiff to be able to process it, I used to just download them from the USGS but now all of their images appear to be black and white and not grey scale.

Answer 1

These training videos might be useful to you.

You can download 1 meter data from the USGS National Map. Select the polygon option, draw a polygon around your area of interest, select the 1 meter option from the 3DEP group. Choose the search product option. The available data layers will appear and you can add them to your cart and download them.

Black & white? The national map thumbnails are images of the elevation data and not hillshades of the data. Your area of interest might just be flat.