Source code for flash.core.data.io.output_transform
# Copyright The PyTorch 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
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
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from typing import Any, Sequence
from flash.core.data.batch import default_uncollate
from flash.core.data.properties import Properties
[docs]class OutputTransform(Properties):
"""The :class:`~flash.core.data.io.output_transform.OutputTransform` encapsulates all the data processing logic
that should run after the model."""
[docs] @staticmethod
def per_batch_transform(batch: Any) -> Any:
"""Transforms to apply on a whole batch before uncollation to individual samples.
Can involve both CPU and Device transforms as this is not applied in separate workers.
"""
return batch
[docs] @staticmethod
def per_sample_transform(sample: Any) -> Any:
"""Transforms to apply to a single sample after splitting up the batch.
Can involve both CPU and Device transforms as this is not applied in separate workers.
"""
return sample
[docs] @staticmethod
def uncollate(batch: Any) -> Any:
"""Uncollates a batch into single samples.
Tries to preserve the type wherever possible.
"""
return default_uncollate(batch)
def __call__(self, batch: Sequence[Any]):
if batch is None:
return batch
uncollated = self.uncollate(self.per_batch_transform(batch))
return [self.per_sample_transform(sample) for sample in uncollated]