Document new EUDEM download

Author: ajnisbet

docs/datasets/eudem.md

@@ -30,45 +30,25 @@ The advantage of the `NODATA` oceans is that you cane use EU-DEM without clippin
 
 ## Adding EU-DEM to Open Topo Data
 
+As of Jan 2024, EU-DEM is no longer available to download via copernicus.eu. 
 
-Make a new folder for the dataset:
+I have uploaded my version of the dataset at [https://files.gpxz.io/eudem_buffered.zip](https://files.gpxz.io/eudem_buffered.zip), see [EUDEM download](https://www.gpxz.io/blog/eudem) for more details.
 
-```bash
-mkdir ./data/eudem
-```
-
-Download the dataset from [Copernicus](https://land.copernicus.eu/imagery-in-situ/eu-dem/eu-dem-v1.1?tab=download). There are 27 files. Unzip them and move all the `.TIF` files into the data folder (you don't need the `.aux.xml`, `.ovr`, or `.TFw` files).
-
-Your data folder should now contain only 27 TIF files:
+Download and unzip the folder into:
 
 ```bash
-ls ./data/eudem
-
-# eu_dem_v11_E00N20.TIF
-# eu_dem_v11_E10N00.TIF
-# eu_dem_v11_E10N10.TIF
-# ...
-```
-
-
-If you have [gdal](https://gdal.org) installed, the easiest thing to do here is build a [VRT](https://gdal.org/drivers/raster/vrt.html) - a single raster file that links to the 27 tiles and which Open Topo Data can treat as a single-file dataset.
-
-```bash
-mkdir ./data/eudem-vrt
-cd ./data/eudem-vrt
-gdalbuildvrt -tr 25 25 -tap -te 0 0 8000000 6000000 eudem.vrt ../eudem/*.TIF
-cd ../../
+mkdir ./data/eudem
 ```
-
-The `tr`, `tap`, and `te` options in the above command ensure that slices from the VRT will use the exact values and grid of the source rasters.
-
+There are 27 files.
 
 Then create a `config.yaml` file:
 
 ```yaml
 datasets:
 - name: eudem25m
-  path: data/eudem-vrt/
+  path: data/eudem
+  filename_epsg: 3035
+  filename_tile_size: 1000000
 ```
 
 Finally, rebuild to enable the new dataset at [localhost:5000/v1/eudem25m?locations=51.575,-3.220](http://localhost:5000/v1/eudem25m?locations=51.575,-3.220).
@@ -82,92 +62,6 @@ make build && make run
     If you don't have gdal installed, you can use the tiles directly. There are instructions for this [here](https://github.com/ajnisbet/opentopodata/blob/f012ec136bebcd97e1dc05645e91a6d2487127dc/docs/datasets/eudem.md#adding-eu-dem-to-open-topo-data), but because the EU-DEM tiles don't come with an overlap you will get a `null` elevation at locations within 0.5 pixels of tile edges. 
 
 
-### Buffering tiles (optional)
-
-The tiles provided by EU-DEM don't overlap and cover slightly less than a 1000km square. This means you'll get a `null` result for coordinates along the tile edges.
-
-The `.vrt` approach above solves the overlap issue, but for improved performance you can leave the tiles separate and add a buffer to each one. This is the code I used on the public API to do this:
-
-
-```python
-import os
-from glob import glob
-import subprocess
-
-import rasterio
-
-
-# Prepare paths.
-input_pattern = 'data/eudem/*.TIF'
-input_paths = sorted(glob(input_pattern))
-assert input_paths
-vrt_path = 'data/eudem-vrt/eudem.vrt'
-output_dir = 'data/eudem-buffered/'
-os.makedirs(output_dir, exist_ok=True)
-
-
-
-# EU-DEM specific options.
-tile_size = 1_000_000
-buffer_size = 50
-
-for input_path in input_paths:
-
-    # Get tile bounds.
-    with rasterio.open(input_path) as f:
-        bottom = int(f.bounds.bottom)
-        left = int(f.bounds.left)
-
-    # For EU-DEM only: round this partial tile down to the nearest tile_size.
-    if left == 943750:
-        left = 0
-
-    # New tile name in SRTM format.
-    output_name = 'N' + str(bottom).zfill(7) + 'E' + str(left).zfill(7) + '.TIF'
-    output_path = os.path.join(output_dir, output_name)
-
-    # New bounds.
-    xmin = left - buffer_size
-    xmax = left + tile_size + buffer_size
-    ymin = bottom - buffer_size
-    ymax = bottom + tile_size + buffer_size
-
-    # EU-DEM tiles don't cover negative locations.
-    xmin = max(0, xmin)
-    ymin = max(0, ymin)
-
-    # Do the transformation.
-    cmd = [
-        'gdal_translate',
-        '-a_srs', 'EPSG:3035',  # EU-DEM crs.
-        '-co', 'NUM_THREADS=ALL_CPUS',
-        '-co', 'COMPRESS=DEFLATE',
-        '-co', 'BIGTIFF=YES',
-        '--config', 'GDAL_CACHEMAX','512',
-        '-projwin', str(xmin), str(ymax), str(xmax), str(ymin),
-        vrt_path, output_path,
-    ]
-    r = subprocess.run(cmd)
-    r.check_returncode()
-```
-
-These new files can be used in Open Topo Data with the following `config.yaml` file
-
-
-```yaml
-datasets:
-- name: eudem25m
-  path: data/eudem-buffered/
-  filename_epsg: 3035
-  filename_tile_size: 1000000
-```
-
-and rebuilding:
-
-```bash
-make build && make run
-```
-
 
 
 ## Public API