/usr/lib/python3/dist-packages/rasterio/warp.py is in python3-rasterio 0.31.0-2build1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 | """Raster warping and reprojection"""
from affine import Affine
from math import ceil
import numpy as np
from rasterio._base import _transform
from rasterio._warp import _transform_geom, _reproject, RESAMPLING
from rasterio.transform import guard_transform
def transform(src_crs, dst_crs, xs, ys, zs=None):
"""
Transform vectors of x, y and optionally z from source
coordinate reference system into target.
Parameters
------------
src_crs: dict
Source coordinate reference system, in rasterio dict format.
Example: {'init': 'EPSG:4326'}
dst_crs: dict
Target coordinate reference system.
xs: array_like
Contains x values. Will be cast to double floating point values.
ys: array_like
Contains y values.
zs: array_like, optional
Contains z values. Assumed to be all 0 if absent.
Returns
---------
out: tuple of array_like, (xs, ys, [zs])
Tuple of x, y, and optionally z vectors, transformed into the target
coordinate reference system.
"""
return _transform(src_crs, dst_crs, xs, ys, zs)
def transform_geom(
src_crs,
dst_crs,
geom,
antimeridian_cutting=False,
antimeridian_offset=10.0,
precision=-1):
"""
Transform geometry from source coordinate reference system into target.
Parameters
------------
src_crs: dict
Source coordinate reference system, in rasterio dict format.
Example: {'init': 'EPSG:4326'}
dst_crs: dict
Target coordinate reference system.
geom: GeoJSON like dict object
antimeridian_cutting: bool, optional
If True, cut geometries at the antimeridian, otherwise geometries will
not be cut (default).
antimeridian_offset: float
Offset from the antimeridian in degrees (default: 10) within which
any geometries will be split.
precision: float
If >= 0, geometry coordinates will be rounded to this number of decimal
places after the transform operation, otherwise original coordinate
values will be preserved (default).
Returns
---------
out: GeoJSON like dict object
Transformed geometry in GeoJSON dict format
"""
return _transform_geom(
src_crs,
dst_crs,
geom,
antimeridian_cutting,
antimeridian_offset,
precision)
def transform_bounds(src_crs, dst_crs, left, bottom, right, top, densify_pts=21):
"""
Transforms bounds from src_crs to dst_crs, optionally densifying the edges
(to account for nonlinear transformations along these edges) and extracting
the outermost bounds.
Note: this does not account for the antimeridian.
Parameters
----------
src_crs: dict
Source coordinate reference system, in rasterio dict format.
Example: {'init': 'EPSG:4326'}
dst_crs: dict
Target coordinate reference system.
left, bottom, right, top: float
Bounding coordinates in src_crs, from the bounds property of a raster.
densify_pts: uint, optional
Number of points to add to each edge to account for nonlinear
edges produced by the transform process. Large numbers will produce
worse performance. Default: 21 (gdal default).
Returns
-------
left, bottom, right, top: float
Outermost coordinates in target coordinate reference system.
"""
if densify_pts < 0:
raise ValueError('densify parameter must be >= 0')
in_xs = []
in_ys = []
if densify_pts > 0:
densify_factor = 1.0 / float(densify_pts + 1)
# Add points along outer edges.
for x in (left, right):
in_xs.extend([x] * (densify_pts + 2))
in_ys.extend(
bottom + np.arange(0, densify_pts + 2, dtype=np.float32)
* ((top - bottom) * densify_factor)
)
for y in (bottom, top):
in_xs.extend(
left + np.arange(1, densify_pts + 1, dtype=np.float32)
* ((right - left) * densify_factor)
)
in_ys.extend([y] * densify_pts)
else:
in_xs = [left, left, right, right]
in_ys = [bottom, top, bottom, top]
xs, ys = transform(src_crs, dst_crs, in_xs, in_ys)
return (min(xs), min(ys), max(xs), max(ys))
def reproject(
source,
destination,
src_transform=None,
src_crs=None,
src_nodata=None,
dst_transform=None,
dst_crs=None,
dst_nodata=None,
resampling=RESAMPLING.nearest,
**kwargs):
"""
Reproject a source raster to a destination raster.
If the source and destination are ndarrays, coordinate reference
system definitions and affine transformation parameters are required
for reprojection.
If the source and destination are rasterio Bands, shorthand for
bands of datasets on disk, the coordinate reference systems and
transforms will be read from the appropriate datasets.
Parameters
------------
source: ndarray or rasterio Band
Source raster.
destination: ndarray or rasterio Band
Target raster.
src_transform: affine transform object, optional
Source affine transformation. Required if source and destination
are ndarrays. Will be derived from source if it is a rasterio Band.
src_crs: dict, optional
Source coordinate reference system, in rasterio dict format.
Required if source and destination are ndarrays.
Will be derived from source if it is a rasterio Band.
Example: {'init': 'EPSG:4326'}
src_nodata: int or float, optional
The source nodata value. Pixels with this value will not be used
for interpolation. If not set, it will be default to the
nodata value of the source image if a masked ndarray or rasterio band,
if available. Must be provided if dst_nodata is not None.
dst_transform: affine transform object, optional
Target affine transformation. Required if source and destination
are ndarrays. Will be derived from target if it is a rasterio Band.
dst_crs: dict, optional
Target coordinate reference system. Required if source and destination
are ndarrays. Will be derived from target if it is a rasterio Band.
dst_nodata: int or float, optional
The nodata value used to initialize the destination; it will remain
in all areas not covered by the reprojected source. Defaults to the
nodata value of the destination image (if set), the value of
src_nodata, or 0 (GDAL default).
resampling: int
Resampling method to use. One of the following:
RESAMPLING.nearest,
RESAMPLING.bilinear,
RESAMPLING.cubic,
RESAMPLING.cubic_spline,
RESAMPLING.lanczos,
RESAMPLING.average,
RESAMPLING.mode
kwargs: dict, optional
Additional arguments passed to transformation function.
Returns
---------
out: None
Output is written to destination.
"""
if src_transform:
src_transform = guard_transform(src_transform).to_gdal()
if dst_transform:
dst_transform = guard_transform(dst_transform).to_gdal()
_reproject(
source,
destination,
src_transform,
src_crs,
src_nodata,
dst_transform,
dst_crs,
dst_nodata,
resampling,
**kwargs)
def calculate_default_transform(
src_crs,
dst_crs,
width,
height,
left,
bottom,
right,
top,
resolution=None,
densify_pts=21):
"""
Transforms bounds to destination coordinate system, calculates resolution
if not provided, and returns destination transform and dimensions.
Intended to be used to calculate parameters for reproject function.
Destination transform is anchored from the left, top coordinate.
Destination width and height are calculated from the number of pixels on
each dimension required to fit the destination bounds.
If resolution is not provided, it is calculated using a weighted average
of the relative sizes of source width and height compared to the transformed
bounds (pixels are assumed to be square).
Parameters
----------
src_crs: dict
Source coordinate reference system, in rasterio dict format.
Example: {'init': 'EPSG:4326'}
dst_crs: dict
Target coordinate reference system.
width: int
Source raster width.
height: int
Source raster height.
left, bottom, right, top: float
Bounding coordinates in src_crs, from the bounds property of a raster.
resolution: tuple (x resolution, y resolution) or float, optional
Target resolution, in units of target coordinate reference system.
densify_pts: uint, optional
Number of points to add to each edge to account for nonlinear
edges produced by the transform process. Large numbers will produce
worse performance. Default: 21 (gdal default).
Returns
-------
tuple of destination affine transform, width, and height
"""
xmin, ymin, xmax, ymax = transform_bounds(
src_crs, dst_crs, left, bottom, right, top, densify_pts)
x_dif = xmax - xmin
y_dif = ymax - ymin
size = float(width + height)
if resolution is None:
# TODO: compare to gdalwarp default
avg_resolution = (
(x_dif / float(width)) * (float(width) / size) +
(y_dif / float(height)) * (float(height) / size)
)
resolution = (avg_resolution, avg_resolution)
elif not isinstance(resolution, (tuple, list)):
resolution = (resolution, resolution)
dst_affine = Affine(resolution[0], 0, xmin, 0, -resolution[1], ymax)
dst_width = max(int(ceil(x_dif / resolution[0])), 1)
dst_height = max(int(ceil(y_dif / resolution[1])), 1)
return dst_affine, dst_width, dst_height
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