Spaces:
Running
on
Zero
Running
on
Zero
import math | |
import torch | |
from torch import nn, Tensor | |
from torch.nn import functional as F | |
from typing import Optional | |
class ShortCut_CrossAttention(nn.Module): | |
def __init__(self, d_model, nhead, panoptic_on = False): | |
super().__init__() | |
self.multihead_attn = nn.MultiheadAttention(d_model, nhead, dropout=0.0) | |
self.norm = nn.LayerNorm(d_model) | |
self.activation = F.relu | |
self._reset_parameters() | |
self.MLP = nn.Linear(d_model, d_model) | |
self.panoptic_on = panoptic_on | |
if panoptic_on: | |
nn.init.constant(self.MLP.weight, 0.0) | |
nn.init.constant(self.MLP.bias, 0.0) | |
def _reset_parameters(self): | |
for p in self.parameters(): | |
if p.dim() > 1: | |
nn.init.xavier_uniform_(p) | |
def with_pos_embed(self, tensor, pos: Optional[Tensor]): | |
return tensor if pos is None else tensor + pos | |
def forward(self, tgt, memory, | |
memory_mask: Optional[Tensor] = None, | |
memory_key_padding_mask: Optional[Tensor] = None, | |
pos: Optional[Tensor] = None, | |
query_pos: Optional[Tensor] = None): | |
tgt2 = self.multihead_attn(query=self.with_pos_embed(tgt, query_pos), | |
key=self.with_pos_embed(memory, pos), | |
value=memory, attn_mask=memory_mask, | |
key_padding_mask=memory_key_padding_mask)[0] | |
if self.panoptic_on: | |
tgt = tgt + self.norm(self.MLP(tgt2)) | |
else: | |
tgt = self.norm(tgt + self.MLP(tgt2)) | |
return tgt | |
class ContentDependentTransfer(nn.Module): | |
def __init__(self, d_model, nhead, panoptic_on): | |
super().__init__() | |
self.pe_layer = PositionEmbeddingSine(d_model//2, normalize=True) | |
self.cross_atten = ShortCut_CrossAttention(d_model = d_model, nhead = nhead, panoptic_on = panoptic_on) | |
def visual_prediction_forward_convnext(self, x): | |
batch, channel, h, w = x.shape | |
x = x.reshape(batch*h*w, channel).unsqueeze(-1).unsqueeze(-1) # fake 2D input | |
x = self.truck_head(x) | |
x = self.head(x) | |
return x.reshape(batch, h, w, x.shape[-1]).permute(0,3,1,2) # B x num_queries x 640 | |
def forward(self, img_feat, text_classifier, ): | |
text_classifier = text_classifier.unsqueeze(0).repeat(img_feat.shape[0],1,1) | |
pos = self.pe_layer(img_feat, None).flatten(2).permute(2, 0, 1) # hw * b * c | |
img_feat = img_feat.flatten(2).permute(2, 0, 1) # hw * b * c | |
bias = self.cross_atten(text_classifier.permute(1, 0, 2), img_feat, memory_mask=None, memory_key_padding_mask=None, pos=pos, query_pos=None) | |
return bias.permute(1, 0, 2) | |
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. | |
""" | |
def __init__(self, num_pos_feats=64, temperature=10000, normalize=False, 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, x, mask=None): | |
if mask is None: | |
mask = torch.zeros((x.size(0), x.size(2), x.size(3)), device=x.device, dtype=torch.bool) | |
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=x.device) | |
dim_t = self.temperature ** (2 * (dim_t // 2) / 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 | |
def __repr__(self, _repr_indent=4): | |
head = "Positional encoding " + self.__class__.__name__ | |
body = [ | |
"num_pos_feats: {}".format(self.num_pos_feats), | |
"temperature: {}".format(self.temperature), | |
"normalize: {}".format(self.normalize), | |
"scale: {}".format(self.scale), | |
] | |
# _repr_indent = 4 | |
lines = [head] + [" " * _repr_indent + line for line in body] | |
return "\n".join(lines) | |