Beispiel #1
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 def raster(self):
     imfield = self.image
     # Check _file attr to avoid opening a file handle.
     if isinstance(getattr(imfield, '_file', None), MemFileIO):
         path = imfield.file.name
     else:
         path = self.image.path
     return greenwich.Raster(path)
Beispiel #2
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 def raster(self):
     imfield = self.image
     # Check _file attr to avoid opening a file handle.
     fileobj = getattr(imfield, '_file', None)
     if isinstance(fileobj, MemFileIO):
         path = imfield.file.name
     elif fileobj and fileobj.name.startswith(tempfile.gettempdir()):
         path = fileobj.name
     else:
         path = self.image.path
     return greenwich.Raster(path)
Beispiel #3
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 def array(self, geom=None, stat=None):
     with greenwich.Raster(self.image.path) as r:
         if geom:
             if geom.num_coords > 1:
                 with r.clip(geom) as clipped:
                     arr = clipped.masked_array()
             else:
                 coord_px = r.affine.transform((geom.coords,)).pop()
                 arr = r.ReadAsArray(*(coord_px + (1, 1)))
         else:
             arr = r.masked_array()
         if arr is not None:
             if stat:
                 arr = getattr(np.ma, stat)(arr)
             if arr.size == 1:
                 arr = arr.item()
         return arr
     raise ValueError('Failure reading array values')
Beispiel #4
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 def convert(self, format=None, geom=None):
     imgpath = self.image.path
     # Handle format as .tif, tif, or tif.zip
     ext = format or os.path.splitext(imgpath)[-1][1:]
     ext = os.path.splitext(ext)[0]
     driver = greenwich.driver_for_path('base.%s' % ext)
     # No conversion is needed if the original format without clipping
     # is requested.
     if not geom and imgpath.endswith(ext):
         return
     memio = MemFileIO()
     if geom:
         with greenwich.Raster(imgpath) as r:
             with r.clip(geom) as clipped:
                 clipped.save(memio, driver)
     else:
         driver.copy(imgpath, memio.name)
     self.image.file = memio
Beispiel #5
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 def clean_fields(self, *args, **kwargs):
     # Override this instead of save() so that fields are populated on
     # save() *or* manager methods like RasterStore.objects.create().
     if not self.image.storage.exists(self.image):
         self.image.save(self.image.name, self.image, save=False)
     with greenwich.Raster(self.image.path) as r:
         band = r[-1]
         bmin, bmax = band.GetMinimum(), band.GetMaximum()
         if bmin is None or bmax is None:
             bmin, bmax = band.ComputeRasterMinMax()
         self.geom = buffer(r.envelope.polygon.ExportToWkb())
         if r.sref.srid:
             self.geom.srid = r.sref.srid
         self.xpixsize, self.ypixsize = r.affine.scale
         self.width, self.height = r.size
         self.minval = bmin
         self.maxval = bmax
         self.nodata = r.nodata
         self.srs = r.sref.wkt
     if self.event is None:
         self.event = datetime.date.today()
     super(AbstractRasterStore, self).clean_fields(*args, **kwargs)
Beispiel #6
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    def warp(self, format=None, srid=None, geom=None):
        """Returns a new RasterQuerySet with possibly warped/converted rasters.

        Keyword args:
        format -- raster file extension format as str
        geom -- geometry for masking or spatial subsetting
        srid -- spatial reference identifier as int for warping to
        """
        clone = self._clone()
        for obj in clone:
            obj.convert(format, geom)
            if srid:
                f = obj.image.file
                if isinstance(f, MemFileIO):
                    r = greenwich.Raster(f.name)
                else:
                    r = obj.raster()
                memio = MemFileIO(delete=False)
                dswarp = r.warp(srid, memio)
                obj.image.file = memio
                dswarp.close()
                r.close()
        return clone
 def convert(self, format=None, geom=None):
     imgpath = self.image.path
     # Handle format as .tif, tif, or tif.zip
     ext = format or os.path.splitext(imgpath)[-1][1:]
     ext = os.path.splitext(ext)[0]
     # No conversion is needed if the original format without clipping
     # is requested.
     if not geom and imgpath.endswith(ext):
         return
     driver = greenwich.driver_for_path(ext, _imgdrivers)
     # Allow overriding of default driver settings.
     settings = self.driver_settings.get(ext)
     if settings:
         driver.settings = settings
     memio = MemFileIO()
     if geom:
         with greenwich.Raster(imgpath) as r, r.clip(geom) as clipped:
             clipped.save(memio, driver)
     else:
         driver.copy(imgpath, memio.name)
     self.image.name = os.extsep.join(
         (os.path.splitext(os.path.basename(imgpath))[0], ext))
     self.image.file = memio
Beispiel #8
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 def quantiles(self, k=5):
     """Returns an ndarray of quantile breaks."""
     with greenwich.Raster(self.image.path) as rast:
         arr = rast.masked_array()
     q = list(np.linspace(0, 100, k))
     return np.percentile(arr.compressed(), q)
Beispiel #9
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 def raster(self):
     return greenwich.Raster(self.image.path)