Exemplo n.º 1
0
def polygonize(raster, threshold_min=0.0, threshold_max=float('inf')):
    """Raster polygonizer.

    Function to polygonize raster. Areas (pixels) with threshold_min <
    pixel_values < threshold_max will be converted to polygons.

    :param raster: Raster layer
    :type raster: QgsRasterLayer

    :param threshold_min: Value that splits raster to flooded or not flooded.
    :type threshold_min: float

    :param threshold_max: Value that splits raster to flooded or not flooded.
    :type threshold_max: float

    :returns: Polygonal geometry
    :rtype: QgsGeometry
    """
    points = pixels_to_points(raster, threshold_min, threshold_max)
    polygons = points_to_rectangles(
        points,
        raster.rasterUnitsPerPixelX(),
        raster.rasterUnitsPerPixelY())
    polygons = union_geometry(polygons)
    return polygons
Exemplo n.º 2
0
def polygonize(raster, threshold_min=0.0, threshold_max=float('inf')):
    """Raster polygonizer.

    Function to polygonize raster. Areas (pixels) with threshold_min <
    pixel_values < threshold_max will be converted to polygons.

    :param raster: Raster layer
    :type raster: QgsRasterLayer

    :param threshold_min: Value that splits raster to flooded or not flooded.
    :type threshold_min: float

    :param threshold_max: Value that splits raster to flooded or not flooded.
    :type threshold_max: float

    :returns: Polygonal geometry
    :rtype: QgsGeometry
    """
    points = pixels_to_points(raster, threshold_min, threshold_max)
    polygons = points_to_rectangles(
        points,
        raster.rasterUnitsPerPixelX(),
        raster.rasterUnitsPerPixelY())
    polygons = union_geometry(polygons)
    return polygons