Python osgeo.gdal.GRA_NearestNeighbour() Examples

The following are 10 code examples of osgeo.gdal.GRA_NearestNeighbour(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module osgeo.gdal , or try the search function .
Example #1
Source File: gdal_python.py    From PyRate with Apache License 2.0 6 votes vote down vote up
def resample_nearest_neighbour(input_tif, extents, new_res, output_file):
    """
    Nearest neighbor resampling and cropping of an image.

    :param str input_tif: input geotiff file path
    :param list extents: new extents for cropping
    :param list[float] new_res: new resolution for resampling
    :param str output_file: output geotiff file path

    :return: dst: resampled image
    :rtype: ndarray
    """
    dst, resampled_proj, src, _ = _crop_resample_setup(extents, input_tif,
                                                       new_res, output_file)
    # Do the work
    gdal.ReprojectImage(src, dst, '', resampled_proj,
                        gdalconst.GRA_NearestNeighbour)
    return dst.ReadAsArray() 
Example #2
Source File: gdal_python.py    From PyRate with Apache License 2.0 6 votes vote down vote up
def _alignment(input_tif, new_res, resampled_average, src_ds_mem,
                      src_gt, tmp_ds):
    """
    Correction step to match python multi-look/crop output to match that of
    Legacy data. Modifies the resampled_average array in place.
    """
    src_ds = gdal.Open(input_tif)
    data = src_ds.GetRasterBand(1).ReadAsArray()
    xlooks = ylooks = int(new_res[0] / src_gt[1])
    xres, yres = _get_resampled_data_size(xlooks, ylooks, data)
    nrows, ncols = resampled_average.shape
    # Legacy nearest neighbor resampling for the last
    # [yres:nrows, xres:ncols] cells without nan_conversion
    # turn off nan-conversion
    src_ds_mem.GetRasterBand(1).SetNoDataValue(LOW_FLOAT32)
    # nearest neighbor resapling
    gdal.ReprojectImage(src_ds_mem, tmp_ds, '', '', gdal.GRA_NearestNeighbour)
    # only take the [yres:nrows, xres:ncols] slice
    if nrows > yres or ncols > xres:
        resampled_nearest_neighbor = tmp_ds.GetRasterBand(1).ReadAsArray()
        resampled_average[yres - nrows:, xres - ncols:] = \
            resampled_nearest_neighbor[yres - nrows:, xres - ncols:] 
Example #3
Source File: test_gdal_python.py    From PyRate with Apache License 2.0 6 votes vote down vote up
def test_reproject_with_no_data(self):

        data = np.array([[2, 7],
                         [2, 7]])
        src_ds = gdal.GetDriverByName('MEM').Create('', 2, 2)
        src_ds.GetRasterBand(1).WriteArray(data)
        src_ds.GetRasterBand(1).SetNoDataValue(2)
        src_ds.SetGeoTransform([10, 1, 0, 10, 0, -1])

        dst_ds = gdal.GetDriverByName('MEM').Create('', 1, 1)
        dst_ds.GetRasterBand(1).SetNoDataValue(3)
        dst_ds.GetRasterBand(1).Fill(3)
        dst_ds.SetGeoTransform([10, 2, 0, 10, 0, -2])

        gdal.ReprojectImage(src_ds, dst_ds, '', '', gdal.GRA_NearestNeighbour)
        got_data = dst_ds.GetRasterBand(1).ReadAsArray()
        expected_data = np.array([[7]])
        np.testing.assert_array_equal(got_data, expected_data) 
Example #4
Source File: test_gdal_python.py    From PyRate with Apache License 2.0 6 votes vote down vote up
def test_reproject_with_no_data_2(self):

        data = np.array([[2, 7, 7, 7],
                         [2, 7, 7, 2]])
        height, width = data.shape
        src_ds = gdal.GetDriverByName('MEM').Create('', width, height)
        src_ds.GetRasterBand(1).WriteArray(data)
        src_ds.GetRasterBand(1).SetNoDataValue(2)
        src_ds.SetGeoTransform([10, 1, 0, 10, 0, -1])

        dst_ds = gdal.GetDriverByName('MEM').Create('', 2, 1)
        dst_ds.GetRasterBand(1).SetNoDataValue(3)
        dst_ds.GetRasterBand(1).Fill(3)
        dst_ds.SetGeoTransform([10, 2, 0, 10, 0, -2])

        gdal.ReprojectImage(src_ds, dst_ds, '', '', gdal.GRA_NearestNeighbour)
        got_data = dst_ds.GetRasterBand(1).ReadAsArray()
        expected_data = np.array([[7, 3]])
        np.testing.assert_array_equal(got_data, expected_data) 
Example #5
Source File: test_gdal_python.py    From PyRate with Apache License 2.0 6 votes vote down vote up
def test_reproject_with_no_data_3(self):

        data = np.array([[2, 7, 7, 7],
                         [2, 7, 7, 7],
                         [2, 7, 7, 7],
                         [2, 7, 7, 2],
                         [2, 7, 7, 2]])
        src_ds = gdal.GetDriverByName('MEM').Create('', 4, 5)
        src_ds.GetRasterBand(1).WriteArray(data)
        src_ds.GetRasterBand(1).SetNoDataValue(2)
        src_ds.SetGeoTransform([10, 1, 0, 10, 0, -1])

        dst_ds = gdal.GetDriverByName('MEM').Create('', 2, 2)
        dst_ds.GetRasterBand(1).SetNoDataValue(3)
        dst_ds.GetRasterBand(1).Fill(3)
        dst_ds.SetGeoTransform([10, 2, 0, 10, 0, -2])

        gdal.ReprojectImage(src_ds, dst_ds, '', '', gdal.GRA_NearestNeighbour)
        got_data = dst_ds.GetRasterBand(1).ReadAsArray()
        expected_data = np.array([[7, 7],
                                  [7, 3]])
        np.testing.assert_array_equal(got_data, expected_data) 
Example #6
Source File: test_gdal_python.py    From PyRate with Apache License 2.0 6 votes vote down vote up
def test_reproject_with_no_data_5(self):

        data = np.array([[2, 7, 7, 7, 2],
                         [2, 7, 7, 7, 2],
                         [2, 7, 7, 7, 2],
                         [2, 7, 7, 2, 2],
                         [2, 7, 7, 2, 2],
                         [2, 7, 7, 2, 2]])
        src_ds = gdal.GetDriverByName('MEM').Create('', 5, 6)
        src_ds.GetRasterBand(1).WriteArray(data)
        src_ds.GetRasterBand(1).SetNoDataValue(2)
        src_ds.SetGeoTransform([10, 1, 0, 10, 0, -1])

        dst_ds = gdal.GetDriverByName('MEM').Create('', 2, 3)
        dst_ds.GetRasterBand(1).SetNoDataValue(3)
        dst_ds.GetRasterBand(1).Fill(3)
        dst_ds.SetGeoTransform([10, 2, 0, 10, 0, -2])

        gdal.ReprojectImage(src_ds, dst_ds, '', '', gdal.GRA_NearestNeighbour)
        got_data = dst_ds.GetRasterBand(1).ReadAsArray()
        expected_data = np.array([[7, 7],
                                  [7, 3],
                                  [7, 3]])
        np.testing.assert_array_equal(got_data, expected_data) 
Example #7
Source File: base.py    From geoio with MIT License 5 votes vote down vote up
def _upsample_from_gdalobj(self,src,dst,method='bilinear'):
        """Hidden to run the actual reprojection gdal code that is called
        from two higher level methods."""

        # Set reprojection method
        if isinstance(method,int):
            pass
        elif method == "nearest":
            method = gdal.GRA_NearestNeighbour
        elif method == "bilinear":
            method = gdal.GRA_Bilinear
        elif method == "cubic":
            method = gdal.GRA_Cubic
        elif method == "average":
            method = gdal.GRA_Average
        else:
            raise ValueError("requested method is not understood.")

        # Do the reprojection
        gdal.ReprojectImage(src,
                            dst,
                            self.meta.projection_string,
                            dst.GetProjection(),
                            method)

        # Return data and free the temp image.
        return dst.ReadAsArray() 
Example #8
Source File: gdal2tiles.py    From gdal2tiles with MIT License 4 votes vote down vote up
def scale_query_to_tile(dsquery, dstile, tiledriver, options, tilefilename=''):
    """Scales down query dataset to the tile dataset"""

    querysize = dsquery.RasterXSize
    tilesize = dstile.RasterXSize
    tilebands = dstile.RasterCount

    if options.resampling == 'average':

        # Function: gdal.RegenerateOverview()
        for i in range(1, tilebands+1):
            # Black border around NODATA
            res = gdal.RegenerateOverview(dsquery.GetRasterBand(i), dstile.GetRasterBand(i),
                                          'average')
            if res != 0:
                exit_with_error("RegenerateOverview() failed on %s, error %d" % (
                    tilefilename, res))

    elif options.resampling == 'antialias':

        # Scaling by PIL (Python Imaging Library) - improved Lanczos
        array = numpy.zeros((querysize, querysize, tilebands), numpy.uint8)
        for i in range(tilebands):
            array[:, :, i] = gdalarray.BandReadAsArray(dsquery.GetRasterBand(i+1),
                                                       0, 0, querysize, querysize)
        im = Image.fromarray(array, 'RGBA')     # Always four bands
        im1 = im.resize((tilesize, tilesize), Image.ANTIALIAS)
        if os.path.exists(tilefilename):
            im0 = Image.open(tilefilename)
            im1 = Image.composite(im1, im0, im1)
        im1.save(tilefilename, tiledriver)

    else:

        if options.resampling == 'near':
            gdal_resampling = gdal.GRA_NearestNeighbour

        elif options.resampling == 'bilinear':
            gdal_resampling = gdal.GRA_Bilinear

        elif options.resampling == 'cubic':
            gdal_resampling = gdal.GRA_Cubic

        elif options.resampling == 'cubicspline':
            gdal_resampling = gdal.GRA_CubicSpline

        elif options.resampling == 'lanczos':
            gdal_resampling = gdal.GRA_Lanczos

        # Other algorithms are implemented by gdal.ReprojectImage().
        dsquery.SetGeoTransform((0.0, tilesize / float(querysize), 0.0, 0.0, 0.0,
                                 tilesize / float(querysize)))
        dstile.SetGeoTransform((0.0, 1.0, 0.0, 0.0, 0.0, 1.0))

        res = gdal.ReprojectImage(dsquery, dstile, None, None, gdal_resampling)
        if res != 0:
            exit_with_error("ReprojectImage() failed on %s, error %d" % (tilefilename, res)) 
Example #9
Source File: raster.py    From wradlib with MIT License 4 votes vote down vote up
def get_raster_elevation(dataset, resample=None, **kwargs):
    """Return surface elevation corresponding to raster dataset
       The resampling algorithm is chosen based on scale ratio

    Parameters
    ----------
    dataset : gdal.Dataset
        raster image with georeferencing (GeoTransform at least)
    resample : GDALResampleAlg
        If None the best algorithm is chosen based on scales.
        GRA_NearestNeighbour = 0, GRA_Bilinear = 1, GRA_Cubic = 2,
        GRA_CubicSpline = 3, GRA_Lanczos = 4, GRA_Average = 5, GRA_Mode = 6,
        GRA_Max = 8, GRA_Min = 9, GRA_Med = 10, GRA_Q1 = 11, GRA_Q3 = 12
    kwargs : keyword arguments
        passed to wradlib.io.dem.get_strm()

    Returns
    -------
    elevation : :class:`numpy:numpy.ndarray`
        Array of shape (rows, cols, 2) containing elevation
    """
    extent = get_raster_extent(dataset)
    src_ds = wradlib.io.dem.get_srtm(extent, **kwargs)

    driver = gdal.GetDriverByName("MEM")
    dst_ds = driver.CreateCopy("ds", dataset)

    if resample is None:
        src_gt = src_ds.GetGeoTransform()
        dst_gt = dst_ds.GetGeoTransform()
        src_scale = min(abs(src_gt[1]), abs(src_gt[5]))
        dst_scale = min(abs(dst_gt[1]), abs(dst_gt[5]))
        ratio = dst_scale / src_scale

        resample = gdal.GRA_Bilinear
        if ratio > 2:
            resample = gdal.GRA_Average
        if ratio < 0.5:
            resample = gdal.GRA_NearestNeighbour

    gdal.ReprojectImage(
        src_ds, dst_ds, src_ds.GetProjection(), dst_ds.GetProjection(), resample
    )
    elevation = read_gdal_values(dst_ds)

    return elevation 
Example #10
Source File: gdal2tiles.py    From gdal2tiles with MIT License 4 votes vote down vote up
def scale_query_to_tile(dsquery, dstile, tiledriver, options, tilefilename=''):
    """Scales down query dataset to the tile dataset"""

    querysize = dsquery.RasterXSize
    tilesize = dstile.RasterXSize
    tilebands = dstile.RasterCount

    if options.resampling == 'average':

        # Function: gdal.RegenerateOverview()
        for i in range(1, tilebands + 1):
            # Black border around NODATA
            res = gdal.RegenerateOverview(dsquery.GetRasterBand(i), dstile.GetRasterBand(i),
                                          'average')
            if res != 0:
                exit_with_error("RegenerateOverview() failed on %s, error %d" % (
                    tilefilename, res))

    elif options.resampling == 'antialias':

        # Scaling by PIL (Python Imaging Library) - improved Lanczos
        array = numpy.zeros((querysize, querysize, tilebands), numpy.uint8)
        for i in range(tilebands):
            array[:, :, i] = gdalarray.BandReadAsArray(dsquery.GetRasterBand(i + 1),
                                                       0, 0, querysize, querysize)
        im = Image.fromarray(array, 'RGBA')     # Always four bands
        im1 = im.resize((tilesize, tilesize), Image.ANTIALIAS)
        if os.path.exists(tilefilename):
            im0 = Image.open(tilefilename)
            im1 = Image.composite(im1, im0, im1)
        im1.save(tilefilename, tiledriver)

    else:

        if options.resampling == 'near':
            gdal_resampling = gdal.GRA_NearestNeighbour

        elif options.resampling == 'bilinear':
            gdal_resampling = gdal.GRA_Bilinear

        elif options.resampling == 'cubic':
            gdal_resampling = gdal.GRA_Cubic

        elif options.resampling == 'cubicspline':
            gdal_resampling = gdal.GRA_CubicSpline

        elif options.resampling == 'lanczos':
            gdal_resampling = gdal.GRA_Lanczos

        # Other algorithms are implemented by gdal.ReprojectImage().
        dsquery.SetGeoTransform((0.0, tilesize / float(querysize), 0.0, 0.0, 0.0,
                                 tilesize / float(querysize)))
        dstile.SetGeoTransform((0.0, 1.0, 0.0, 0.0, 0.0, 1.0))

        res = gdal.ReprojectImage(dsquery, dstile, None, None, gdal_resampling)
        if res != 0:
            exit_with_error("ReprojectImage() failed on %s, error %d" % (tilefilename, res))