substrate_raster.py 文件源码

def rasterize_polygons(polygon_shp, template_raster, out_raster, field):
    """ generate a categorical raster based on polygons

    :rtype: None
    :param polygon_shp: input polygon shapefile
    :param template_raster: raster template for cellsize and extent
    :param out_raster: output raster file
    """

    # Source: https://pcjericks.github.io/py-gdalogr-cookbook/raster_layers.html

    gdal.UseExceptions()
    # Get template raster specs
    src_ds = gdal.Open(template_raster)
    if src_ds is None:
        print 'Unable to open %s' % template_raster
        sys.exit(1)
    try:
        srcband = src_ds.GetRasterBand(1)
    except RuntimeError, e:
        print 'No band %i found' % 0
        print e
        sys.exit(1)

    # Open the data source and read in the extent
    source_ds = ogr.Open(polygon_shp)
    source_layer = source_ds.GetLayer()

    target_ds = gdal.GetDriverByName('GTiff').Create(out_raster, src_ds.RasterXSize, src_ds.RasterYSize, 1, gdal.GDT_Float32)
    target_ds.SetGeoTransform(src_ds.GetGeoTransform())
    target_ds.SetProjection(src_ds.GetProjection())
    band = target_ds.GetRasterBand(1)
    band.SetNoDataValue(srcband.GetNoDataValue())

    # Rasterize
    gdal.RasterizeLayer(target_ds, [1], source_layer, options=["ATTRIBUTE={}".format(field)])