Merge pull request #112 from OpenDataAnalytics/raster-bbox

Raster bbox

.gitignore

@@ -40,6 +40,7 @@ htmlcov/
 .cache
 nosetests.xml
 coverage.xml
+tests/data/output/
 
 # Translations
 *.mo

conda_env.yml

@@ -18,4 +18,5 @@ dependencies:
 - pillow
 - gdal
 - psycopg2
-- geoalchemy2
+- geoalchemy2
+- rasterio

gaia/geo/gdal_functions.py

@@ -24,6 +24,9 @@
 import gdalconst
 import numpy
 import gdal
+import shapely
+import rasterio
+import rasterio.features
 from gaia import GaiaException
 try:
     import gdalnumeric
@@ -445,6 +448,39 @@ def gdal_zonalstats(zones, raster):
     return list(gen_zonalstats(zones, raster))
 
 
+def rasterio_bbox(raster_input):
+    """
+    This function will return bounding box information
+    for a raster layer.
+
+    :param raster_input: raster input filepath
+    :return: list of coordinates in (xmin, ymin, xmax, ymax) format
+    """
+
+    footprint = rasterio_footprint(raster_input)
+    shape = shapely.geometry.Polygon(footprint)
+    return list(shape.bounds)
+
+
+def rasterio_footprint(raster_input):
+    """
+    This function will return the footprint of a raster
+    layer
+
+    :param raster_input: raster input filepath
+    :return: list of coordinates
+    """
+    with rasterio.open(raster_input) as dataset:
+        # Read the dataset's valid data mask as a ndarray.
+        mask = dataset.dataset_mask()
+
+        # Extract feature shapes and values from the array.
+        feature = rasterio.features.shapes(mask, transform=dataset.affine)
+        footprint = next(feature)[0]
+        shape = shapely.geometry.shape(json.loads(json.dumps(footprint)))
+        return list(shape.minimum_rotated_rectangle.exterior.coords)
+
+
 def gen_zonalstats(zones_json, raster):
     """
     Generator function that yields the statistics of a raster dataset

gaia/geo/geo_inputs.py

@@ -37,6 +37,7 @@
 from gaia.inputs import GaiaIO, FileIO, UnsupportedFormatException
 from gaia.filters import filter_pandas, filter_postgis
 from gaia.geo.gdal_functions import gdal_reproject
+from gaia.geo.gdal_functions import rasterio_bbox, rasterio_footprint
 
 
 class VectorMixin(object):
@@ -254,6 +255,14 @@ def read(self, as_numpy_array=False, as_single_band=True,
         else:
             return out_data
 
+    def get_bbox(self):
+        """Return bounding box of the dataset"""
+        return rasterio_bbox(self.uri)
+
+    def get_footprint(self):
+        """Return footpring of the dataset"""
+        return rasterio_footprint(self.uri)
+
 
 class ProcessIO(GaiaIO):
     """IO for nested GaiaProcess objects"""

requirements.txt

@@ -22,3 +22,4 @@ pillow>=3.1.1
 gdal>=2.1.0
 psycopg2>=2.6.1
 geoalchemy2>=0.2.6
+rasterio>=0.36.0

tests/cases/test_processors.py

@@ -261,6 +261,29 @@ def test_distance(self):
             if process:
                 process.purge()
 
+    def test_raster_bbox(self):
+        raster_io = RasterFileIO(
+            uri=os.path.join(testfile_path,
+                             'satellite_test_data',
+                             'LC81070352015218LGN00_B5.TIF'))
+
+        bbox = raster_io.get_bbox()
+        self.assertEquals(bbox, [307366.7298195886, 3869968.931078481,
+                                 539974.1151507461, 4107482.3190209507])
+
+    def test_raster_footprint(self):
+        raster_io = RasterFileIO(
+            uri=os.path.join(testfile_path,
+                             'satellite_test_data',
+                             'LC81070352015218LGN00_B5.TIF'))
+
+        footprint = raster_io.get_footprint()
+        self.assertEquals(footprint, [(354404.6484867488, 4107482.3190209507),
+                                      (307366.7298195886, 3915415.660631991),
+                                      (492936.19648358587, 3869968.931078481),
+                                      (539974.1151507461, 4062035.5894674407),
+                                      (354404.6484867488, 4107482.3190209507)])
+
     def test_subset_raster(self):
         """
         Test SubsetProcess for vector & raster inputs