raster.py 文件源码

def __init__(self, filename):
        if os.path.isfile(filename):
            self.filename = filename if os.path.isabs(filename) else os.path.join(os.getcwd(), filename)
            self.raster = gdal.Open(filename, GA_ReadOnly)
        else:
            raise IOError('file does not exist')

        self.cols = self.raster.RasterXSize
        self.rows = self.raster.RasterYSize
        self.bands = self.raster.RasterCount
        self.dim = [self.rows, self.cols, self.bands]
        self.driver = self.raster.GetDriver()
        self.format = self.driver.ShortName
        self.dtype = gdal.GetDataTypeName(self.raster.GetRasterBand(1).DataType)
        self.projection = self.raster.GetProjection()
        self.srs = osr.SpatialReference(wkt=self.projection)
        self.proj4 = self.srs.ExportToProj4()
        try:
            self.epsg = crsConvert(self.srs, 'epsg')
        except RuntimeError:
            self.epsg = None
        self.geogcs = self.srs.GetAttrValue('geogcs')
        self.projcs = self.srs.GetAttrValue('projcs') if self.srs.IsProjected() else None
        self.geo = dict(
            zip(['xmin', 'xres', 'rotation_x', 'ymax', 'rotation_y', 'yres'], self.raster.GetGeoTransform()))

        # note: yres is negative!
        self.geo['xmax'] = self.geo['xmin'] + self.geo['xres'] * self.cols
        self.geo['ymin'] = self.geo['ymax'] + self.geo['yres'] * self.rows

        self.res = [abs(float(self.geo['xres'])), abs(float(self.geo['yres']))]
        self.nodata = self.raster.GetRasterBand(1).GetNoDataValue()

        self.__data = []