RasterStats#
- class RasterStats[source]#
Bases:
object
Band-wise means and standard deviations.
Attributes
Channel variances, if self.stds is set.
- __init__(means: Optional[ndarray] = None, stds: Optional[ndarray] = None, counts: Optional[ndarray] = None)[source]#
Constructor.
- Parameters
means (Optional[np.ndarray]) – Band means. Defaults to None.
stds (Optional[np.ndarray]) – Band standard deviations. Defaults to None.
counts (Optional[np.ndarray]) – Band pixel counts (used to compute the specified means and stds). Defaults to None.
Methods
__init__
([means, stds, counts])Constructor.
compute
(raster_sources[, sample_prob, ...])Compute the mean and stds over all the raster_sources.
compute_from_chips
(chips[, running_mean, ...])Compute running mean and var from chips in stream.
compute_from_pixels
(pixels[, running_mean, ...])Update running mean and var from pixel values.
load
(stats_uri)Load stats from file.
save
(stats_uri)Save stats to file.
to_dict
()- __init__(means: Optional[ndarray] = None, stds: Optional[ndarray] = None, counts: Optional[ndarray] = None)[source]#
Constructor.
- Parameters
means (Optional[np.ndarray]) – Band means. Defaults to None.
stds (Optional[np.ndarray]) – Band standard deviations. Defaults to None.
counts (Optional[np.ndarray]) – Band pixel counts (used to compute the specified means and stds). Defaults to None.
- compute(raster_sources: Sequence[RasterSource], sample_prob: Optional[float] = None, chip_sz: int = 300, stride: Optional[int] = None, nodata_value: Optional[float] = 0) None [source]#
Compute the mean and stds over all the raster_sources.
This ignores NODATA values if nodata_value is not None.
If sample_prob is set, then a subset of each scene is used to compute stats which speeds up the computation. Roughly speaking, if sample_prob=0.5, then half the pixels in the scene will be used. More precisely, the number of chips is equal to sample_prob * (width * height / 300^2), or 1, whichever is greater. Each chip is uniformly sampled from the scene with replacement. Otherwise, it uses a sliding window over the entire scene to compute stats.
- Parameters
Sequence['RasterSource'] (raster_sources) – List of RasterSources.
sample_prob (Optional[float]) – Pixel sampling probability. See notes above. Defaults to None.
nodata_value (Optional[float]) – NODATA value. If set, these pixels will be ignored when computing stats.
raster_sources (Sequence[RasterSource]) –
chip_sz (int) –
- Return type
None
- compute_from_chips(chips: Iterable[ndarray], running_mean: Optional[ndarray] = None, running_var: Optional[ndarray] = None, running_count: Optional[ndarray] = None) Union[Tuple[None, None, None], Tuple[ndarray, ndarray, ndarray]] [source]#
Compute running mean and var from chips in stream.
- compute_from_pixels(pixels: ndarray, running_mean: Optional[ndarray] = None, running_var: Optional[ndarray] = None, running_count: Optional[ndarray] = None) Tuple[ndarray, ndarray, ndarray] [source]#
Update running mean and var from pixel values.
- classmethod load(stats_uri: str) RasterStats [source]#
Load stats from file.
- Parameters
stats_uri (str) –
- Return type