mmocr/projects/SPTS/spts/model/position_embedding.py
Tong Gao 2d743cfa19
[Model] SPTS (#1696)
* [Feature] Add RepeatAugSampler

* initial commit

* spts inference done

* merge repeat_aug (bug in multi-node?)

* fix inference

* train done

* rm readme

* Revert "merge repeat_aug (bug in multi-node?)"

This reverts commit 393506a97cbe6d75ad1f28611ea10eba6b8fa4b3.

* Revert "[Feature] Add RepeatAugSampler"

This reverts commit 2089b02b4844157670033766f257b5d1bca452ce.

* remove utils

* readme & conversion script

* update readme

* fix

* optimize

* rename cfg & del compose

* fix

* fix
2023-02-01 11:58:03 +08:00

56 lines
1.9 KiB
Python

import math
import torch
from torch import Tensor, nn
class PositionEmbeddingSine(nn.Module):
"""This is a more standard version of the position embedding, very similar
to the one used by the Attention is all you need paper, generalized to work
on images.
Adapted from https://github.com/shannanyinxiang/SPTS.
"""
def __init__(self,
num_pos_feats=64,
temperature=10000,
normalize=True,
scale=None):
super().__init__()
self.num_pos_feats = num_pos_feats
self.temperature = temperature
self.normalize = normalize
if scale is not None and normalize is False:
raise ValueError('normalize should be True if scale is passed')
if scale is None:
scale = 2 * math.pi
self.scale = scale
def forward(self, mask: Tensor):
assert mask is not None
not_mask = ~mask
y_embed = not_mask.cumsum(1, dtype=torch.float32)
x_embed = not_mask.cumsum(2, dtype=torch.float32)
if self.normalize:
eps = 1e-6
y_embed = y_embed / (y_embed[:, -1:, :] + eps) * self.scale
x_embed = x_embed / (x_embed[:, :, -1:] + eps) * self.scale
dim_t = torch.arange(
self.num_pos_feats, dtype=torch.float32, device=mask.device)
dim_t = self.temperature**(2 *
torch.div(dim_t, 2, rounding_mode='floor') /
self.num_pos_feats)
pos_x = x_embed[:, :, :, None] / dim_t
pos_y = y_embed[:, :, :, None] / dim_t
pos_x = torch.stack(
(pos_x[:, :, :, 0::2].sin(), pos_x[:, :, :, 1::2].cos()),
dim=4).flatten(3)
pos_y = torch.stack(
(pos_y[:, :, :, 0::2].sin(), pos_y[:, :, :, 1::2].cos()),
dim=4).flatten(3)
pos = torch.cat((pos_y, pos_x), dim=3).permute(0, 3, 1, 2)
return pos