stable-diffusion-webui/modules/prompt_parser.py

205 lines
6.7 KiB
Python

import re
from collections import namedtuple
import torch
from lark import Lark, Transformer, Visitor
import functools
import modules.shared as shared
# a prompt like this: "fantasy landscape with a [mountain:lake:0.25] and [an oak:a christmas tree:0.75][ in foreground::0.6][ in background:0.25] [shoddy:masterful:0.5]"
# will be represented with prompt_schedule like this (assuming steps=100):
# [25, 'fantasy landscape with a mountain and an oak in foreground shoddy']
# [50, 'fantasy landscape with a lake and an oak in foreground in background shoddy']
# [60, 'fantasy landscape with a lake and an oak in foreground in background masterful']
# [75, 'fantasy landscape with a lake and an oak in background masterful']
# [100, 'fantasy landscape with a lake and a christmas tree in background masterful']
def get_learned_conditioning_prompt_schedules(prompts, steps):
grammar = r"""
start: prompt
prompt: (emphasized | scheduled | weighted | plain)*
!emphasized: "(" prompt ")"
| "(" prompt ":" prompt ")"
| "[" prompt "]"
scheduled: "[" (prompt ":")? prompt ":" NUMBER "]"
!weighted: "{" weighted_item ("|" weighted_item)* "}"
!weighted_item: prompt (":" prompt)?
plain: /([^\\\[\](){}:|]|\\.)+/
%import common.SIGNED_NUMBER -> NUMBER
"""
parser = Lark(grammar, parser='lalr')
def collect_steps(steps, tree):
l = [steps]
class CollectSteps(Visitor):
def scheduled(self, tree):
tree.children[-1] = float(tree.children[-1])
if tree.children[-1] < 1:
tree.children[-1] *= steps
tree.children[-1] = min(steps, int(tree.children[-1]))
l.append(tree.children[-1])
CollectSteps().visit(tree)
return sorted(set(l))
def at_step(step, tree):
class AtStep(Transformer):
def scheduled(self, args):
if len(args) == 2:
before, after, when = (), *args
else:
before, after, when = args
yield before if step <= when else after
def start(self, args):
def flatten(x):
if type(x) == str:
yield x
else:
for gen in x:
yield from flatten(gen)
return ''.join(flatten(args[0]))
def plain(self, args):
yield args[0].value
def __default__(self, data, children, meta):
for child in children:
yield from child
return AtStep().transform(tree)
@functools.cache
def get_schedule(prompt):
tree = parser.parse(prompt)
return [[t, at_step(t, tree)] for t in collect_steps(steps, tree)]
return [get_schedule(prompt) for prompt in prompts]
ScheduledPromptConditioning = namedtuple("ScheduledPromptConditioning", ["end_at_step", "cond"])
ScheduledPromptBatch = namedtuple("ScheduledPromptBatch", ["shape", "schedules"])
def get_learned_conditioning(prompts, steps):
res = []
prompt_schedules = get_learned_conditioning_prompt_schedules(prompts, steps)
cache = {}
for prompt, prompt_schedule in zip(prompts, prompt_schedules):
cached = cache.get(prompt, None)
if cached is not None:
res.append(cached)
continue
texts = [x[1] for x in prompt_schedule]
conds = shared.sd_model.get_learned_conditioning(texts)
cond_schedule = []
for i, (end_at_step, text) in enumerate(prompt_schedule):
cond_schedule.append(ScheduledPromptConditioning(end_at_step, conds[i]))
cache[prompt] = cond_schedule
res.append(cond_schedule)
return ScheduledPromptBatch((len(prompts),) + res[0][0].cond.shape, res)
def reconstruct_cond_batch(c: ScheduledPromptBatch, current_step):
res = torch.zeros(c.shape, device=shared.device, dtype=next(shared.sd_model.parameters()).dtype)
for i, cond_schedule in enumerate(c.schedules):
target_index = 0
for curret_index, (end_at, cond) in enumerate(cond_schedule):
if current_step <= end_at:
target_index = curret_index
break
res[i] = cond_schedule[target_index].cond
return res
re_attention = re.compile(r"""
\\\(|
\\\)|
\\\[|
\\]|
\\\\|
\\|
\(|
\[|
:([+-]?[.\d]+)\)|
\)|
]|
[^\\()\[\]:]+|
:
""", re.X)
def parse_prompt_attention(text):
"""
Parses a string with attention tokens and returns a list of pairs: text and its assoicated weight.
Accepted tokens are:
(abc) - increases attention to abc by a multiplier of 1.1
(abc:3.12) - increases attention to abc by a multiplier of 3.12
[abc] - decreases attention to abc by a multiplier of 1.1
\( - literal character '('
\[ - literal character '['
\) - literal character ')'
\] - literal character ']'
\\ - literal character '\'
anything else - just text
Example:
'a (((house:1.3)) [on] a (hill:0.5), sun, (((sky))).'
produces:
[
['a ', 1.0],
['house', 1.5730000000000004],
[' ', 1.1],
['on', 1.0],
[' a ', 1.1],
['hill', 0.55],
[', sun, ', 1.1],
['sky', 1.4641000000000006],
['.', 1.1]
]
"""
res = []
round_brackets = []
square_brackets = []
round_bracket_multiplier = 1.1
square_bracket_multiplier = 1 / 1.1
def multiply_range(start_position, multiplier):
for p in range(start_position, len(res)):
res[p][1] *= multiplier
for m in re_attention.finditer(text):
text = m.group(0)
weight = m.group(1)
if text.startswith('\\'):
res.append([text[1:], 1.0])
elif text == '(':
round_brackets.append(len(res))
elif text == '[':
square_brackets.append(len(res))
elif weight is not None and len(round_brackets) > 0:
multiply_range(round_brackets.pop(), float(weight))
elif text == ')' and len(round_brackets) > 0:
multiply_range(round_brackets.pop(), round_bracket_multiplier)
elif text == ']' and len(square_brackets) > 0:
multiply_range(square_brackets.pop(), square_bracket_multiplier)
else:
res.append([text, 1.0])
for pos in round_brackets:
multiply_range(pos, round_bracket_multiplier)
for pos in square_brackets:
multiply_range(pos, square_bracket_multiplier)
if len(res) == 0:
res = [["", 1.0]]
return res