RSPrompter / mmdet /models /layers /transformer /conditional_detr_layers.py
KyanChen's picture
Upload 787 files
3e06e1c
# Copyright (c) OpenMMLab. All rights reserved.
import torch
from mmcv.cnn import build_norm_layer
from mmcv.cnn.bricks.transformer import FFN
from torch import Tensor
from torch.nn import ModuleList
from .detr_layers import DetrTransformerDecoder, DetrTransformerDecoderLayer
from .utils import MLP, ConditionalAttention, coordinate_to_encoding
class ConditionalDetrTransformerDecoder(DetrTransformerDecoder):
"""Decoder of Conditional DETR."""
def _init_layers(self) -> None:
"""Initialize decoder layers and other layers."""
self.layers = ModuleList([
ConditionalDetrTransformerDecoderLayer(**self.layer_cfg)
for _ in range(self.num_layers)
])
self.embed_dims = self.layers[0].embed_dims
self.post_norm = build_norm_layer(self.post_norm_cfg,
self.embed_dims)[1]
# conditional detr affline
self.query_scale = MLP(self.embed_dims, self.embed_dims,
self.embed_dims, 2)
self.ref_point_head = MLP(self.embed_dims, self.embed_dims, 2, 2)
# we have substitute 'qpos_proj' with 'qpos_sine_proj' except for
# the first decoder layer), so 'qpos_proj' should be deleted
# in other layers.
for layer_id in range(self.num_layers - 1):
self.layers[layer_id + 1].cross_attn.qpos_proj = None
def forward(self,
query: Tensor,
key: Tensor = None,
query_pos: Tensor = None,
key_pos: Tensor = None,
key_padding_mask: Tensor = None):
"""Forward function of decoder.
Args:
query (Tensor): The input query with shape
(bs, num_queries, dim).
key (Tensor): The input key with shape (bs, num_keys, dim) If
`None`, the `query` will be used. Defaults to `None`.
query_pos (Tensor): The positional encoding for `query`, with the
same shape as `query`. If not `None`, it will be added to
`query` before forward function. Defaults to `None`.
key_pos (Tensor): The positional encoding for `key`, with the
same shape as `key`. If not `None`, it will be added to
`key` before forward function. If `None`, and `query_pos`
has the same shape as `key`, then `query_pos` will be used
as `key_pos`. Defaults to `None`.
key_padding_mask (Tensor): ByteTensor with shape (bs, num_keys).
Defaults to `None`.
Returns:
List[Tensor]: forwarded results with shape (num_decoder_layers,
bs, num_queries, dim) if `return_intermediate` is True, otherwise
with shape (1, bs, num_queries, dim). References with shape
(bs, num_queries, 2).
"""
reference_unsigmoid = self.ref_point_head(
query_pos) # [bs, num_queries, 2]
reference = reference_unsigmoid.sigmoid()
reference_xy = reference[..., :2]
intermediate = []
for layer_id, layer in enumerate(self.layers):
if layer_id == 0:
pos_transformation = 1
else:
pos_transformation = self.query_scale(query)
# get sine embedding for the query reference
ref_sine_embed = coordinate_to_encoding(coord_tensor=reference_xy)
# apply transformation
ref_sine_embed = ref_sine_embed * pos_transformation
query = layer(
query,
key=key,
query_pos=query_pos,
key_pos=key_pos,
key_padding_mask=key_padding_mask,
ref_sine_embed=ref_sine_embed,
is_first=(layer_id == 0))
if self.return_intermediate:
intermediate.append(self.post_norm(query))
if self.return_intermediate:
return torch.stack(intermediate), reference
query = self.post_norm(query)
return query.unsqueeze(0), reference
class ConditionalDetrTransformerDecoderLayer(DetrTransformerDecoderLayer):
"""Implements decoder layer in Conditional DETR transformer."""
def _init_layers(self):
"""Initialize self-attention, cross-attention, FFN, and
normalization."""
self.self_attn = ConditionalAttention(**self.self_attn_cfg)
self.cross_attn = ConditionalAttention(**self.cross_attn_cfg)
self.embed_dims = self.self_attn.embed_dims
self.ffn = FFN(**self.ffn_cfg)
norms_list = [
build_norm_layer(self.norm_cfg, self.embed_dims)[1]
for _ in range(3)
]
self.norms = ModuleList(norms_list)
def forward(self,
query: Tensor,
key: Tensor = None,
query_pos: Tensor = None,
key_pos: Tensor = None,
self_attn_masks: Tensor = None,
cross_attn_masks: Tensor = None,
key_padding_mask: Tensor = None,
ref_sine_embed: Tensor = None,
is_first: bool = False):
"""
Args:
query (Tensor): The input query, has shape (bs, num_queries, dim)
key (Tensor, optional): The input key, has shape (bs, num_keys,
dim). If `None`, the `query` will be used. Defaults to `None`.
query_pos (Tensor, optional): The positional encoding for `query`,
has the same shape as `query`. If not `None`, it will be
added to `query` before forward function. Defaults to `None`.
ref_sine_embed (Tensor): The positional encoding for query in
cross attention, with the same shape as `x`. Defaults to None.
key_pos (Tensor, optional): The positional encoding for `key`, has
the same shape as `key`. If not None, it will be added to
`key` before forward function. If None, and `query_pos` has
the same shape as `key`, then `query_pos` will be used for
`key_pos`. Defaults to None.
self_attn_masks (Tensor, optional): ByteTensor mask, has shape
(num_queries, num_keys), Same in `nn.MultiheadAttention.
forward`. Defaults to None.
cross_attn_masks (Tensor, optional): ByteTensor mask, has shape
(num_queries, num_keys), Same in `nn.MultiheadAttention.
forward`. Defaults to None.
key_padding_mask (Tensor, optional): ByteTensor, has shape
(bs, num_keys). Defaults to None.
is_first (bool): A indicator to tell whether the current layer
is the first layer of the decoder. Defaults to False.
Returns:
Tensor: Forwarded results, has shape (bs, num_queries, dim).
"""
query = self.self_attn(
query=query,
key=query,
query_pos=query_pos,
key_pos=query_pos,
attn_mask=self_attn_masks)
query = self.norms[0](query)
query = self.cross_attn(
query=query,
key=key,
query_pos=query_pos,
key_pos=key_pos,
attn_mask=cross_attn_masks,
key_padding_mask=key_padding_mask,
ref_sine_embed=ref_sine_embed,
is_first=is_first)
query = self.norms[1](query)
query = self.ffn(query)
query = self.norms[2](query)
return query