depth_anything_3/model/dinov2/layers/layer_scale.py

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the license found in the
# LICENSE file in the root directory of this source tree.

# Modified from: https://github.com/huggingface/pytorch-image-models/blob/main/timm/models/vision_transformer.py#L103-L110  # noqa: E501

from typing import Union
import torch
from torch import Tensor, nn


class LayerScale(nn.Module):
    def __init__(
        self,
        dim: int,
        init_values: Union[float, Tensor] = 1e-5,
        inplace: bool = False,
    ) -> None:
        super().__init__()
        self.dim = dim
        self.inplace = inplace
        self.init_values = init_values
        self.gamma = nn.Parameter(init_values * torch.ones(dim))

    def forward(self, x: Tensor) -> Tensor:
        return x.mul_(self.gamma) if self.inplace else x * self.gamma

    def extra_repr(self) -> str:
        return f"{self.dim}, init_values={self.init_values}, inplace={self.inplace}"