cosmos_transfer1/diffusion/training/callbacks/low_precision.py

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# SPDX-License-Identifier: Apache-2.0
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# Licensed under the Apache License, Version 2.0 (the "License");
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#
# http://www.apache.org/licenses/LICENSE-2.0
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import torch

from cosmos_transfer1.utils.callback import LowPrecisionCallback as BaseCallback
from cosmos_transfer1.utils.config import Config
from cosmos_transfer1.utils.model import Model
from cosmos_transfer1.utils.trainer import Trainer


class LowPrecisionCallback(BaseCallback):
    """
    Config with non-primitive type makes it difficult to override the option.
    The callback gets precision from model.precision instead.
    """

    def __init__(self, config: Config, trainer: Trainer, update_iter: int):
        self.config = config
        self.trainer = trainer
        self.update_iter = update_iter

    def on_train_start(self, model: Model, iteration: int = 0) -> None:
        assert model.precision in [
            torch.bfloat16,
            torch.float16,
            torch.half,
        ], "LowPrecisionCallback must use a low precision dtype."
        self.precision_type = model.precision