Georeference + Crop Google Earth images (or any other images) in QGIS 3

So we're going to georeference the image, then crop the georeferenced images so they are rectangles, and not warped monstrosities. and BONUS get the latitude and longitude of the top-left corner and the bottom-right corner!!!

Unbelievable!

Export an image from Google Earth

Yes, it would be nice if the earth were a nice flat projection in Google Earth. No, you can't make the earth a nice flat projection in Google Earth. We're globes-only now, because that's life.

1. Open Google Earth Pro (the desktop version)
2. Browse to where you want to be.
3. Click the Save image button
4. Increase the resolution of your image + remove all of the extraneous elements
5. Click Save image to save your image

Adding our reference layer

First we need to add a Google Maps-ish underlay. We'll use it to match up where your map belongs.

These are called "XYZ" layers, and they're built into QGIS. You can click and drag them from the Browser panel into your Layers panel. I'm using OpenStreetMap, because it's apparently the only one already in QGIS.

If you don't have the Browser panel, you can select View > Panels > Browser to make it appear.

But honestly, that isn't going to be helpful! We probably want something with mountains and stuff so we can match up our map better, right?

Right-click XYZ Tiles and click New Connection. We'll need the URL format - I think this site is a pretty good overview of providers, you just need the whole {z}/{x}/{y}.png URL thing. For example, a nice one might be ESRI.WorldImagery, since it has mountains and stuff:

https://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{z}/{y}/{x}

Fill in the box..

And then drag it to your map!

{z} is zoom, and {x} and {y} are the coordinates of the file.

Georeferencing

Now we need to georeference, which is how you give your image a latitude/longitude (and stretch it to make it look 'right').

Go to Raster > Georeferencer

Click the box in the top left to add a new raster image. When it asks you for your CRS, pick WGS 84 EPSG:4326 (I actually don't think it matters).

Now you'll need to match up points on your image with points on your basemap. First, click somewhere on your image that is memorable - the edge of a peninsula, or a curve in the land or something.

QGIS will ask you, where is this?

You don't memorize lat and lon of random points in the world, so you click From map canvas.

Click the same point in your XYZ layer and tada!, it filled the points in for you. Click OK.

Do this a million times, and eventually you'll have a million georeferenced points. The more the better! Be sure to get lots of things close to the edges.

Now click the gear icon to change the settings, because the defaults are real bad.

According to this random internet person you should use Polynomial 3 for Transformation type and Lanczos for Resampling method.

Make sure you've selected an output file and Load in QGIS when done is checked and click OK

Now click the green play button. It'll take some time thinking, then..... it'll look like nothing happened! But if you minimize the georeferencer you'll see it got exported and put onto the map.

To check that it's okay, right click the new layer, select Properties, go to the Transparency section and dial it down to 50% or so.

How well does it match up?

If it doesn't look good, delete the layer, open the georeferencer window (remember you only minimized it!) and add some more points or delete ones you did poorly.

Once you're satisfied, you can close the georeferencing plugin. It'll ask if you want to save the points.... but I say no!

Clipping our raster

Now we have a beautiful image that is way too big and with all kinds of weird black stuff where it got stretched to fit on the map.

Let's crop it! Select Raster > Extraction > Clip Raster by Extent.

Your Input layer is the layer we just georeferenced. It asks for our clipping extent - the boundaries - but we have no idea! Click the ... button and pick Select Extent on Canvas.

Unlike the georeferencer, this menu doesn't get out of the way. Just move it to the side or minimize it or something, then click and drag to mark the area you'd like to crop for your map.

It will draw a red box for you, and when you release the mouse it'll fill in the extent field.

Scroll down in the menu (even though it looks like you can't), and tell it you want to save the result as a file. Click Run.

This might not work! You might get an error about gdal_translate not being found! If that happens, swear gently at QGIS but keep in mind it's totally free, and use this fix here

Hide your old ugly gross layer and bask in the joy of your new awesome beautiful layer!

Getting the latitude and longitude of the top left and bottom right (or layer bounds or whatever)

There is probably a better way to do this, but I don't know what it is. Here's my bad way!

Now you probably need to know the corners of your new layer.

First, pretend you're going to export the image.

Now change the CRS to be EPSG:4326 - WGS 84. The default CRS is something about meters, but we want latitude and longitude!

Once you've changed the CRS to EPSG:4326, you'll see the North/West/Earth/South numbers look like beautiful perfect latitudes and longitudes.

In this case, your top left is 48.241863045, -124.783742788 and your bottom right is 24.440317236,-73.951903924.

Life is great. 🎉 🗺 🎉 🗺 🎉

I just put the coordinates in there with Photoshop, that's not black magic

A little bit more, maybe?

To turn the cropped image into something useful, go find the .tif you saved (remember when you picked to save it as a real file instead of a temporary file?), open it in literally any image editing software, and re-save it as a jpeg.