# Copyright The Lightning team. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from collections.abc import Sequence from typing import Any, List, Optional, Union from torch import Tensor, tensor from typing_extensions import Literal from torchmetrics.functional.image.sam import _sam_compute, _sam_update from torchmetrics.metric import Metric from torchmetrics.utilities import rank_zero_warn from torchmetrics.utilities.data import dim_zero_cat from torchmetrics.utilities.imports import _MATPLOTLIB_AVAILABLE from torchmetrics.utilities.plot import _AX_TYPE, _PLOT_OUT_TYPE if not _MATPLOTLIB_AVAILABLE: __doctest_skip__ = ["SpectralAngleMapper.plot"] class SpectralAngleMapper(Metric): """`Spectral Angle Mapper`_ determines the spectral similarity between image spectra and reference spectra. It works by calculating the angle between the spectra, where small angles between indicate high similarity and high angles indicate low similarity. As input to ``forward`` and ``update`` the metric accepts the following input - ``preds`` (:class:`~torch.Tensor`): Predictions from model of shape ``(N,C,H,W)`` - ``target`` (:class:`~torch.Tensor`): Ground truth values of shape ``(N,C,H,W)`` As output of `forward` and `compute` the metric returns the following output - ``sam`` (:class:`~torch.Tensor`): if ``reduction!='none'`` returns float scalar tensor with average SAM value over sample else returns tensor of shape ``(N,)`` with SAM values per sample Args: reduction: a method to reduce metric score over labels. - ``'elementwise_mean'``: takes the mean (default) - ``'sum'``: takes the sum - ``'none'`` or ``None``: no reduction will be applied kwargs: Additional keyword arguments, see :ref:`Metric kwargs` for more info. Return: Tensor with SpectralAngleMapper score Example: >>> from torch import rand >>> from torchmetrics.image import SpectralAngleMapper >>> preds = rand([16, 3, 16, 16]) >>> target = rand([16, 3, 16, 16]) >>> sam = SpectralAngleMapper() >>> sam(preds, target) tensor(0.5914) """ higher_is_better: bool = False is_differentiable: bool = True full_state_update: bool = False plot_lower_bound: float = 0.0 plot_upper_bound: float = 1.0 preds: List[Tensor] target: List[Tensor] sum_sam: Tensor numel: Tensor def __init__( self, reduction: Optional[Literal["elementwise_mean", "sum", "none"]] = "elementwise_mean", **kwargs: Any, ) -> None: super().__init__(**kwargs) if reduction not in ("elementwise_mean", "sum", "none", None): raise ValueError( f"The `reduction` {reduction} is not valid. Valid options are `elementwise_mean`, `sum`, `none`, None." ) if reduction == "none" or reduction is None: rank_zero_warn( "Metric `SpectralAngleMapper` will save all targets and predictions in the buffer when using" "`reduction=None` or `reduction='none'. For large datasets, this may lead to a large memory footprint." ) self.add_state("preds", default=[], dist_reduce_fx="cat") self.add_state("target", default=[], dist_reduce_fx="cat") else: self.add_state("sum_sam", tensor(0.0), dist_reduce_fx="sum") self.add_state("numel", tensor(0), dist_reduce_fx="sum") self.reduction = reduction def update(self, preds: Tensor, target: Tensor) -> None: """Update state with predictions and targets.""" preds, target = _sam_update(preds, target) if self.reduction == "none" or self.reduction is None: self.preds.append(preds) self.target.append(target) else: sam_score = _sam_compute(preds, target, reduction="sum") self.sum_sam += sam_score p_shape = preds.shape self.numel += p_shape[0] * p_shape[2] * p_shape[3] def compute(self) -> Tensor: """Compute spectra over state.""" if self.reduction == "none" or self.reduction is None: preds = dim_zero_cat(self.preds) target = dim_zero_cat(self.target) return _sam_compute(preds, target, self.reduction) return self.sum_sam / self.numel if self.reduction == "elementwise_mean" else self.sum_sam def plot( self, val: Optional[Union[Tensor, Sequence[Tensor]]] = None, ax: Optional[_AX_TYPE] = None ) -> _PLOT_OUT_TYPE: """Plot a single or multiple values from the metric. Args: val: Either a single result from calling `metric.forward` or `metric.compute` or a list of these results. If no value is provided, will automatically call `metric.compute` and plot that result. ax: An matplotlib axis object. If provided will add plot to that axis Returns: Figure and Axes object Raises: ModuleNotFoundError: If `matplotlib` is not installed .. plot:: :scale: 75 >>> # Example plotting single value >>> from torch import rand >>> from torchmetrics.image import SpectralAngleMapper >>> preds = rand([16, 3, 16, 16]) >>> target = rand([16, 3, 16, 16]) >>> metric = SpectralAngleMapper() >>> metric.update(preds, target) >>> fig_, ax_ = metric.plot() .. plot:: :scale: 75 >>> # Example plotting multiple values >>> from torch import rand >>> from torchmetrics.image import SpectralAngleMapper >>> preds = rand([16, 3, 16, 16]) >>> target = rand([16, 3, 16, 16]) >>> metric = SpectralAngleMapper() >>> values = [ ] >>> for _ in range(10): ... values.append(metric(preds, target)) >>> fig_, ax_ = metric.plot(values) """ return self._plot(val, ax)