File size: 7,233 Bytes
ee823b7
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
# Copyright 2022 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import numpy as np
import torch
from typing import Optional, Union, Tuple, Dict
from einops import rearrange, repeat


def register_attention_control(model, controller):
    def block_forward(self, place_in_unet):

        def forward(
            hidden_states,
            encoder_hidden_states=None,
            timestep=None,
            attention_mask=None,
            video_length=None,
        ):
            # SparseCausal-Attention
            norm_hidden_states = (
                self.norm1(hidden_states, timestep)
                if self.use_ada_layer_norm
                else self.norm1(hidden_states)
            )

            norm_hidden_states, k_input, v_input = controller(
                norm_hidden_states, video_length, place_in_unet
            )

            if self.unet_use_cross_frame_attention:
                hidden_states = (
                    self.attn1(
                        norm_hidden_states,
                        k_input=k_input,
                        v_input=v_input,
                        attention_mask=attention_mask,
                        video_length=video_length,
                    )
                    + hidden_states
                )
            else:
                hidden_states = (
                    self.attn1(
                        norm_hidden_states,
                        k_input=k_input,
                        v_input=v_input,
                        attention_mask=attention_mask,
                    )
                    + hidden_states
                )

            if self.attn2 is not None:
                # Cross-Attention
                norm_hidden_states = (
                    self.norm2(hidden_states, timestep)
                    if self.use_ada_layer_norm
                    else self.norm2(hidden_states)
                )
                norm_hidden_states, _, _ = controller(
                    norm_hidden_states, video_length, place_in_unet
                )
                hidden_states = (
                    self.attn2(
                        norm_hidden_states,
                        encoder_hidden_states=encoder_hidden_states,
                        attention_mask=attention_mask,
                    )
                    + hidden_states
                )

            # Feed-forward
            hidden_states = self.ff(self.norm3(hidden_states)) + hidden_states

            # Temporal-Attention
            if self.unet_use_temporal_attention:
                d = hidden_states.shape[1]
                hidden_states = rearrange(
                    hidden_states, "(b f) d c -> (b d) f c", f=video_length
                )
                norm_hidden_states = (
                    self.norm_temp(hidden_states, timestep)
                    if self.use_ada_layer_norm
                    else self.norm_temp(hidden_states)
                )
                norm_hidden_states, _, _ = controller(
                    norm_hidden_states, d, place_in_unet
                )
                hidden_states = self.attn_temp(norm_hidden_states) + hidden_states
                hidden_states = rearrange(hidden_states, "(b d) f c -> (b f) d c", d=d)

            return hidden_states

        return forward

    def register_recr(net_, count, place_in_unet):
        if net_.__class__.__name__ == "BasicTransformerBlock":
            net_.forward = block_forward(net_, place_in_unet)
            # net_.__class__.__name__ = "BasicTransformerBlock_edit"
            return count + 1
        elif hasattr(net_, "children"):
            for net__ in net_.children():
                count = register_recr(net__, count, place_in_unet)
        return count

    cross_att_count = 0
    sub_nets = model.unet.named_children()
    for net in sub_nets:
        if "down" in net[0]:
            cross_att_count += register_recr(net[1], 0, "down")
        elif "up" in net[0]:
            cross_att_count += register_recr(net[1], 0, "up")
        elif "mid" in net[0]:
            cross_att_count += register_recr(net[1], 0, "mid")
    controller.num_att_layers = cross_att_count * 2


def get_word_inds(text: str, word_place: int, tokenizer):
    split_text = text.split(" ")
    if type(word_place) is str:
        word_place = [i for i, word in enumerate(split_text) if word_place == word]
    elif type(word_place) is int:
        word_place = [word_place]
    out = []
    if len(word_place) > 0:
        words_encode = [
            tokenizer.decode([item]).strip("#") for item in tokenizer.encode(text)
        ][1:-1]
        cur_len, ptr = 0, 0

        for i in range(len(words_encode)):
            cur_len += len(words_encode[i])
            if ptr in word_place:
                out.append(i + 1)
            if cur_len >= len(split_text[ptr]):
                ptr += 1
                cur_len = 0
    return np.array(out)


def update_alpha_time_word(
    alpha,
    bounds: Union[float, Tuple[float, float]],
    prompt_ind: int,
    word_inds: Optional[torch.Tensor] = None,
):
    if type(bounds) is float:
        bounds = 0, bounds
    start, end = int(bounds[0] * alpha.shape[0]), int(bounds[1] * alpha.shape[0])
    if word_inds is None:
        word_inds = torch.arange(alpha.shape[2])
    alpha[:start, prompt_ind, word_inds] = 0
    alpha[start:end, prompt_ind, word_inds] = 1
    alpha[end:, prompt_ind, word_inds] = 0
    return alpha


def get_time_words_attention_alpha(
    prompts,
    num_steps,
    cross_replace_steps: Union[
        float, Tuple[float, float], Dict[str, Tuple[float, float]]
    ],
    tokenizer,
    max_num_words=77,
):
    if type(cross_replace_steps) is not dict:
        cross_replace_steps = {"default_": cross_replace_steps}
    if "default_" not in cross_replace_steps:
        cross_replace_steps["default_"] = (0.0, 1.0)
    alpha_time_words = torch.zeros(num_steps + 1, len(prompts) - 1, max_num_words)
    for i in range(len(prompts) - 1):
        alpha_time_words = update_alpha_time_word(
            alpha_time_words, cross_replace_steps["default_"], i
        )
    for key, item in cross_replace_steps.items():
        if key != "default_":
            inds = [
                get_word_inds(prompts[i], key, tokenizer)
                for i in range(1, len(prompts))
            ]
            for i, ind in enumerate(inds):
                if len(ind) > 0:
                    alpha_time_words = update_alpha_time_word(
                        alpha_time_words, item, i, ind
                    )
    alpha_time_words = alpha_time_words.reshape(
        num_steps + 1, len(prompts) - 1, 1, 1, max_num_words
    )  # time, batch, heads, pixels, words
    return alpha_time_words