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| 1 | +#!/usr/bin/env python |
| 2 | +# -*- coding: utf-8 -*- |
| 3 | +# Copyright (c) 2024 Satpy developers |
| 4 | +# |
| 5 | +# This file is part of satpy. |
| 6 | +# |
| 7 | +# satpy is free software: you can redistribute it and/or modify it under the |
| 8 | +# terms of the GNU General Public License as published by the Free Software |
| 9 | +# Foundation, either version 3 of the License, or (at your option) any later |
| 10 | +# version. |
| 11 | +# |
| 12 | +# satpy is distributed in the hope that it will be useful, but WITHOUT ANY |
| 13 | +# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
| 14 | +# A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
| 15 | +# |
| 16 | +# You should have received a copy of the GNU General Public License along with |
| 17 | +# satpy. If not, see <http://www.gnu.org/licenses/>. |
| 18 | +"""MCD12Q1 hdf-eos format reader. |
| 19 | +
|
| 20 | +Introduction |
| 21 | +------------ |
| 22 | +
|
| 23 | +The ``mcd12q1`` reader reads MCD12Q1 products in HDF-EOS format. |
| 24 | +
|
| 25 | +The 500m product is provided on a sinusoidal grid. |
| 26 | +
|
| 27 | +Reference documents and links: |
| 28 | + - MODIS land products grid: https://modis-land.gsfc.nasa.gov/MODLAND_grid.html |
| 29 | + - User guide: https://lpdaac.usgs.gov/documents/101/MCD12_User_Guide_V6.pdf |
| 30 | + - MCD12Q1 v061: MODIS/Terra+Aqua Land Cover Type Yearly L3 Global 500 m SIN Grid |
| 31 | +
|
| 32 | +The reader has been tested with: |
| 33 | + - MCD12Q1: Land cover data. |
| 34 | +
|
| 35 | +To get a list of the available datasets for a given file refer to the "Load data" section in :doc:`../reading`. |
| 36 | +
|
| 37 | +""" |
| 38 | +import logging |
| 39 | +from typing import Iterable |
| 40 | + |
| 41 | +from pyresample import geometry |
| 42 | + |
| 43 | +from satpy.readers.hdfeos_base import HDFEOSBaseFileReader |
| 44 | + |
| 45 | +logger = logging.getLogger(__name__) |
| 46 | + |
| 47 | + |
| 48 | +class MCD12Q1HDFFileHandler(HDFEOSBaseFileReader): |
| 49 | + """File handler for MCD12Q1 HDF-EOS 500m granules.""" |
| 50 | + def available_datasets(self, configured_datasets=None): |
| 51 | + """Automatically determine datasets provided by this file.""" |
| 52 | + # Initialise set of variable names to carry through code |
| 53 | + handled_var_names = set() |
| 54 | + |
| 55 | + ds_dict = self.sd.datasets() |
| 56 | + |
| 57 | + for is_avail, ds_info in (configured_datasets or []): |
| 58 | + file_key = ds_info.get("file_key", ds_info["name"]) |
| 59 | + # we must add all variables here even if another file handler has |
| 60 | + # claimed the variable. It could be another instance of this file |
| 61 | + # type, and we don't want to add that variable dynamically if the |
| 62 | + # other file handler defined it by the YAML definition. |
| 63 | + handled_var_names.add(file_key) |
| 64 | + if is_avail is not None: |
| 65 | + # some other file handler said it has this dataset |
| 66 | + # we don't know any more information than the previous |
| 67 | + # file handler so let's yield early |
| 68 | + yield is_avail, ds_info |
| 69 | + continue |
| 70 | + if self.file_type_matches(ds_info["file_type"]) is None: |
| 71 | + # this is not the file type for this dataset |
| 72 | + yield None, ds_info |
| 73 | + continue |
| 74 | + yield file_key in ds_dict.keys(), ds_info |
| 75 | + |
| 76 | + yield from self._dynamic_variables_from_file(handled_var_names) |
| 77 | + |
| 78 | + def _dynamic_variables_from_file(self, handled_var_names: set) -> Iterable[tuple[bool, dict]]: |
| 79 | + res = self._get_res() |
| 80 | + for var_name in self.sd.datasets().keys(): |
| 81 | + if var_name in handled_var_names: |
| 82 | + # skip variables that YAML had configured |
| 83 | + continue |
| 84 | + common = {"file_type": "mcd12q1_500m_hdf", |
| 85 | + "resolution": res, |
| 86 | + "name": var_name} |
| 87 | + yield True, common |
| 88 | + |
| 89 | + |
| 90 | + def _get_res(self): |
| 91 | + """Compute the resolution from the file metadata.""" |
| 92 | + gridname = self.metadata["GridStructure"]["GRID_1"]["GridName"] |
| 93 | + if "MCD12Q1" not in gridname: |
| 94 | + raise ValueError("Only MCD12Q1 grids are supported") |
| 95 | + |
| 96 | + resolution_string = self.metadata["ARCHIVEDMETADATA"]["NADIRDATARESOLUTION"]["VALUE"] |
| 97 | + if resolution_string[-1] == "m": |
| 98 | + return int(resolution_string.removesuffix("m")) |
| 99 | + else: |
| 100 | + raise ValueError("Cannot parse resolution of MCD12Q1 grid") |
| 101 | + |
| 102 | + |
| 103 | + def get_dataset(self, dataset_id, dataset_info): |
| 104 | + """Get DataArray for specified dataset.""" |
| 105 | + dataset_name = dataset_id["name"] |
| 106 | + # xxx |
| 107 | + dataset = self.load_dataset(dataset_name, dataset_info.pop("category", False)) |
| 108 | + |
| 109 | + self._add_satpy_metadata(dataset_id, dataset) |
| 110 | + |
| 111 | + return dataset |
| 112 | + |
| 113 | + def _get_area_extent(self): |
| 114 | + """Get the grid properties.""" |
| 115 | + # Now compute the data extent |
| 116 | + upperleft = self.metadata["GridStructure"]["GRID_1"]["UpperLeftPointMtrs"] |
| 117 | + lowerright = self.metadata["GridStructure"]["GRID_1"]["LowerRightMtrs"] |
| 118 | + |
| 119 | + return upperleft[0], lowerright[1], lowerright[0], upperleft[1] |
| 120 | + |
| 121 | + def get_area_def(self, dsid): |
| 122 | + """Get the area definition. |
| 123 | +
|
| 124 | + This is fixed, but not defined in the file. So we must |
| 125 | + generate it ourselves with some assumptions. |
| 126 | +
|
| 127 | + The proj_param string comes from https://lpdaac.usgs.gov/documents/101/MCD12_User_Guide_V6.pdf |
| 128 | + """ |
| 129 | + proj_param = "proj=sinu +a=6371007.181 +b=6371007.181 +units=m" |
| 130 | + |
| 131 | + # Get the size of the dataset |
| 132 | + nrows = self.metadata["GridStructure"]["GRID_1"]["YDim"] |
| 133 | + ncols = self.metadata["GridStructure"]["GRID_1"]["XDim"] |
| 134 | + |
| 135 | + # Construct the area definition |
| 136 | + area = geometry.AreaDefinition("sinusoidal_modis", |
| 137 | + "Tiled sinusoidal L3 MODIS area", |
| 138 | + "sinusoidal", |
| 139 | + proj_param, |
| 140 | + ncols, |
| 141 | + nrows, |
| 142 | + self._get_area_extent()) |
| 143 | + |
| 144 | + return area |
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