Code

gdalwarp -t_srs EPSG:4326 path/to/input.tif path/to/output.tif

Motivation

Reprojecting a raster dataset allows you to change its coordinate system to match another project or map. This can be useful when working with datasets that have different coordinate systems and need to be aligned.

Explanation

• gdalwarp: This is the command for the GDAL raster reprojection and warping utility.
• -t_srs EPSG:4326: Specifies the target coordinate system to which the input raster dataset will be reprojected. In this example, EPSG:4326 corresponds to the WGS84 geographic coordinate system, commonly used in GPS systems.
• path/to/input.tif: Specifies the path to the input raster dataset.
• path/to/output.tif: Specifies the path where the reprojected raster dataset will be saved.

Example Output

The input raster dataset will be reprojected to EPSG:4326 (WGS84) and saved as path/to/output.tif in the desired coordinate system.

Crop a raster dataset by using specific coordinates

Code

gdalwarp -te min_x min_y max_x max_y -te_srs EPSG:4326 path/to/input.tif path/to/output.tif

Motivation

Cropping a raster dataset by specific coordinates allows you to extract a smaller region of interest from a larger raster. This can be useful when you only need to work with a subset of the data or when you want to focus on a specific area.

Explanation

• gdalwarp: This is the command for the GDAL raster reprojection and warping utility.
• -te min_x min_y max_x max_y: Specifies the minimum and maximum coordinates for the cropping extent. These coordinates should be in the same coordinate system as the input raster dataset.
• -te_srs EPSG:4326: Specifies the coordinate system for the cropping extent. In this example, EPSG:4326 corresponds to the WGS84 geographic coordinate system, commonly used in GPS systems.
• path/to/input.tif: Specifies the path to the input raster dataset.
• path/to/output.tif: Specifies the path where the cropped raster dataset will be saved.

Example Output

The output raster dataset will be a cropped version of the input raster, containing only the region defined by the specified coordinates. The cropped dataset will be saved as path/to/output.tif.

Crop a raster dataset using a vector layer

Code

gdalwarp -cutline path/to/area_to_cut.geojson -crop_to_cutline path/to/input.tif path/to/output.tif

Motivation

Using a vector layer to crop a raster dataset allows you to define the cropping extent based on a specific shape or boundary. This can be useful when you want to extract a raster subset that corresponds to a specific area defined by a polygon, such as an administrative boundary or a study area.

Explanation

• gdalwarp: This is the command for the GDAL raster reprojection and warping utility.
• -cutline path/to/area_to_cut.geojson: Specifies the path to the vector layer that will be used to define the cropping extent. The vector layer should be in a format supported by GDAL, such as GeoJSON.
• -crop_to_cutline: Specifies that the output raster should be cropped to the extent defined by the vector layer.
• path/to/input.tif: Specifies the path to the input raster dataset.
• path/to/output.tif: Specifies the path where the cropped raster dataset will be saved.

Example Output

The output raster dataset will be a cropped version of the input raster, containing only the region defined by the boundaries of the vector layer. The cropped dataset will be saved as path/to/output.tif.