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Kohya-ss-sd-scripts/flux_minimal_inference.py

408 lines
14 KiB
Python

# Minimum Inference Code for FLUX
import argparse
import datetime
import math
import os
import random
from typing import Callable, List, Optional, Tuple
import einops
import numpy as np
import torch
from tqdm import tqdm
from PIL import Image
import accelerate
from library import device_utils
from library.device_utils import init_ipex, get_preferred_device
init_ipex()
from library.utils import setup_logging, str_to_dtype
setup_logging()
import logging
logger = logging.getLogger(__name__)
import networks.lora_flux as lora_flux
from library import flux_models, flux_utils, sd3_utils, strategy_flux
def time_shift(mu: float, sigma: float, t: torch.Tensor):
return math.exp(mu) / (math.exp(mu) + (1 / t - 1) ** sigma)
def get_lin_function(x1: float = 256, y1: float = 0.5, x2: float = 4096, y2: float = 1.15) -> Callable[[float], float]:
m = (y2 - y1) / (x2 - x1)
b = y1 - m * x1
return lambda x: m * x + b
def get_schedule(
num_steps: int,
image_seq_len: int,
base_shift: float = 0.5,
max_shift: float = 1.15,
shift: bool = True,
) -> list[float]:
# extra step for zero
timesteps = torch.linspace(1, 0, num_steps + 1)
# shifting the schedule to favor high timesteps for higher signal images
if shift:
# eastimate mu based on linear estimation between two points
mu = get_lin_function(y1=base_shift, y2=max_shift)(image_seq_len)
timesteps = time_shift(mu, 1.0, timesteps)
return timesteps.tolist()
def denoise(
model: flux_models.Flux,
img: torch.Tensor,
img_ids: torch.Tensor,
txt: torch.Tensor,
txt_ids: torch.Tensor,
vec: torch.Tensor,
timesteps: list[float],
guidance: float = 4.0,
t5_attn_mask: Optional[torch.Tensor] = None,
):
# this is ignored for schnell
guidance_vec = torch.full((img.shape[0],), guidance, device=img.device, dtype=img.dtype)
for t_curr, t_prev in zip(tqdm(timesteps[:-1]), timesteps[1:]):
t_vec = torch.full((img.shape[0],), t_curr, dtype=img.dtype, device=img.device)
pred = model(
img=img,
img_ids=img_ids,
txt=txt,
txt_ids=txt_ids,
y=vec,
timesteps=t_vec,
guidance=guidance_vec,
txt_attention_mask=t5_attn_mask,
)
img = img + (t_prev - t_curr) * pred
return img
def do_sample(
accelerator: Optional[accelerate.Accelerator],
model: flux_models.Flux,
img: torch.Tensor,
img_ids: torch.Tensor,
l_pooled: torch.Tensor,
t5_out: torch.Tensor,
txt_ids: torch.Tensor,
num_steps: int,
guidance: float,
t5_attn_mask: Optional[torch.Tensor],
is_schnell: bool,
device: torch.device,
flux_dtype: torch.dtype,
):
timesteps = get_schedule(num_steps, img.shape[1], shift=not is_schnell)
# denoise initial noise
if accelerator:
with accelerator.autocast(), torch.no_grad():
x = denoise(
model, img, img_ids, t5_out, txt_ids, l_pooled, timesteps=timesteps, guidance=guidance, t5_attn_mask=t5_attn_mask
)
else:
with torch.autocast(device_type=device.type, dtype=flux_dtype), torch.no_grad():
x = denoise(
model, img, img_ids, t5_out, txt_ids, l_pooled, timesteps=timesteps, guidance=guidance, t5_attn_mask=t5_attn_mask
)
return x
def generate_image(
model,
clip_l,
t5xxl,
ae,
prompt: str,
seed: Optional[int],
image_width: int,
image_height: int,
steps: Optional[int],
guidance: float,
):
seed = seed if seed is not None else random.randint(0, 2**32 - 1)
logger.info(f"Seed: {seed}")
# make first noise with packed shape
# original: b,16,2*h//16,2*w//16, packed: b,h//16*w//16,16*2*2
packed_latent_height, packed_latent_width = math.ceil(image_height / 16), math.ceil(image_width / 16)
noise = torch.randn(
1,
packed_latent_height * packed_latent_width,
16 * 2 * 2,
device=device,
dtype=dtype,
generator=torch.Generator(device=device).manual_seed(seed),
)
# prepare img and img ids
# this is needed only for img2img
# img = rearrange(img, "b c (h ph) (w pw) -> b (h w) (c ph pw)", ph=2, pw=2)
# if img.shape[0] == 1 and bs > 1:
# img = repeat(img, "1 ... -> bs ...", bs=bs)
# txt2img only needs img_ids
img_ids = flux_utils.prepare_img_ids(1, packed_latent_height, packed_latent_width)
# prepare embeddings
logger.info("Encoding prompts...")
tokens_and_masks = tokenize_strategy.tokenize(prompt)
clip_l = clip_l.to(device)
t5xxl = t5xxl.to(device)
with torch.no_grad():
if is_fp8(clip_l_dtype) or is_fp8(t5xxl_dtype):
clip_l.to(clip_l_dtype)
t5xxl.to(t5xxl_dtype)
with accelerator.autocast():
_, t5_out, txt_ids, t5_attn_mask = encoding_strategy.encode_tokens(
tokenize_strategy, [clip_l, t5xxl], tokens_and_masks, args.apply_t5_attn_mask
)
else:
with torch.autocast(device_type=device.type, dtype=clip_l_dtype):
l_pooled, _, _, _ = encoding_strategy.encode_tokens(tokenize_strategy, [clip_l, None], tokens_and_masks)
with torch.autocast(device_type=device.type, dtype=t5xxl_dtype):
_, t5_out, txt_ids, t5_attn_mask = encoding_strategy.encode_tokens(
tokenize_strategy, [None, t5xxl], tokens_and_masks, args.apply_t5_attn_mask
)
# NaN check
if torch.isnan(l_pooled).any():
raise ValueError("NaN in l_pooled")
if torch.isnan(t5_out).any():
raise ValueError("NaN in t5_out")
if args.offload:
clip_l = clip_l.cpu()
t5xxl = t5xxl.cpu()
# del clip_l, t5xxl
device_utils.clean_memory()
# generate image
logger.info("Generating image...")
model = model.to(device)
if steps is None:
steps = 4 if is_schnell else 50
img_ids = img_ids.to(device)
t5_attn_mask = t5_attn_mask.to(device) if args.apply_t5_attn_mask else None
x = do_sample(
accelerator, model, noise, img_ids, l_pooled, t5_out, txt_ids, steps, guidance, t5_attn_mask, is_schnell, device, flux_dtype
)
if args.offload:
model = model.cpu()
# del model
device_utils.clean_memory()
# unpack
x = x.float()
x = einops.rearrange(x, "b (h w) (c ph pw) -> b c (h ph) (w pw)", h=packed_latent_height, w=packed_latent_width, ph=2, pw=2)
# decode
logger.info("Decoding image...")
ae = ae.to(device)
with torch.no_grad():
if is_fp8(ae_dtype):
with accelerator.autocast():
x = ae.decode(x)
else:
with torch.autocast(device_type=device.type, dtype=ae_dtype):
x = ae.decode(x)
if args.offload:
ae = ae.cpu()
x = x.clamp(-1, 1)
x = x.permute(0, 2, 3, 1)
img = Image.fromarray((127.5 * (x + 1.0)).float().cpu().numpy().astype(np.uint8)[0])
# save image
output_dir = args.output_dir
os.makedirs(output_dir, exist_ok=True)
output_path = os.path.join(output_dir, f"{datetime.datetime.now().strftime('%Y%m%d_%H%M%S')}.png")
img.save(output_path)
logger.info(f"Saved image to {output_path}")
if __name__ == "__main__":
target_height = 768 # 1024
target_width = 1360 # 1024
# steps = 50 # 28 # 50
# guidance_scale = 5
# seed = 1 # None # 1
device = get_preferred_device()
parser = argparse.ArgumentParser()
parser.add_argument("--ckpt_path", type=str, required=True)
parser.add_argument("--clip_l", type=str, required=False)
parser.add_argument("--t5xxl", type=str, required=False)
parser.add_argument("--ae", type=str, required=False)
parser.add_argument("--apply_t5_attn_mask", action="store_true")
parser.add_argument("--prompt", type=str, default="A photo of a cat")
parser.add_argument("--output_dir", type=str, default=".")
parser.add_argument("--dtype", type=str, default="bfloat16", help="base dtype")
parser.add_argument("--clip_l_dtype", type=str, default=None, help="dtype for clip_l")
parser.add_argument("--ae_dtype", type=str, default=None, help="dtype for ae")
parser.add_argument("--t5xxl_dtype", type=str, default=None, help="dtype for t5xxl")
parser.add_argument("--flux_dtype", type=str, default=None, help="dtype for flux")
parser.add_argument("--seed", type=int, default=None)
parser.add_argument("--steps", type=int, default=None, help="Number of steps. Default is 4 for schnell, 50 for dev")
parser.add_argument("--guidance", type=float, default=3.5)
parser.add_argument("--offload", action="store_true", help="Offload to CPU")
parser.add_argument(
"--lora_weights",
type=str,
nargs="*",
default=[],
help="LoRA weights, only supports networks.lora_flux, each argument is a `path;multiplier` (semi-colon separated)",
)
parser.add_argument("--merge_lora_weights", action="store_true", help="Merge LoRA weights to model")
parser.add_argument("--width", type=int, default=target_width)
parser.add_argument("--height", type=int, default=target_height)
parser.add_argument("--interactive", action="store_true")
args = parser.parse_args()
seed = args.seed
steps = args.steps
guidance_scale = args.guidance
name = "schnell" if "schnell" in args.ckpt_path else "dev" # TODO change this to a more robust way
is_schnell = name == "schnell"
def is_fp8(dt):
return dt in [torch.float8_e4m3fn, torch.float8_e4m3fnuz, torch.float8_e5m2, torch.float8_e5m2fnuz]
dtype = str_to_dtype(args.dtype)
clip_l_dtype = str_to_dtype(args.clip_l_dtype, dtype)
t5xxl_dtype = str_to_dtype(args.t5xxl_dtype, dtype)
ae_dtype = str_to_dtype(args.ae_dtype, dtype)
flux_dtype = str_to_dtype(args.flux_dtype, dtype)
logger.info(f"Dtypes for clip_l, t5xxl, ae, flux: {clip_l_dtype}, {t5xxl_dtype}, {ae_dtype}, {flux_dtype}")
loading_device = "cpu" if args.offload else device
use_fp8 = [is_fp8(d) for d in [dtype, clip_l_dtype, t5xxl_dtype, ae_dtype, flux_dtype]]
if any(use_fp8):
accelerator = accelerate.Accelerator(mixed_precision="bf16")
else:
accelerator = None
# load clip_l
logger.info(f"Loading clip_l from {args.clip_l}...")
clip_l = flux_utils.load_clip_l(args.clip_l, clip_l_dtype, loading_device)
clip_l.eval()
logger.info(f"Loading t5xxl from {args.t5xxl}...")
t5xxl = flux_utils.load_t5xxl(args.t5xxl, t5xxl_dtype, loading_device)
t5xxl.eval()
if is_fp8(clip_l_dtype):
clip_l = accelerator.prepare(clip_l)
if is_fp8(t5xxl_dtype):
t5xxl = accelerator.prepare(t5xxl)
t5xxl_max_length = 256 if is_schnell else 512
tokenize_strategy = strategy_flux.FluxTokenizeStrategy(t5xxl_max_length)
encoding_strategy = strategy_flux.FluxTextEncodingStrategy()
# DiT
model = flux_utils.load_flow_model(name, args.ckpt_path, None, loading_device)
model.eval()
logger.info(f"Casting model to {flux_dtype}")
model.to(flux_dtype) # make sure model is dtype
if is_fp8(flux_dtype):
model = accelerator.prepare(model)
# AE
ae = flux_utils.load_ae(name, args.ae, ae_dtype, loading_device)
ae.eval()
if is_fp8(ae_dtype):
ae = accelerator.prepare(ae)
# LoRA
lora_models: List[lora_flux.LoRANetwork] = []
for weights_file in args.lora_weights:
if ";" in weights_file:
weights_file, multiplier = weights_file.split(";")
multiplier = float(multiplier)
else:
multiplier = 1.0
lora_model, weights_sd = lora_flux.create_network_from_weights(
multiplier, weights_file, ae, [clip_l, t5xxl], model, None, True
)
if args.merge_lora_weights:
lora_model.merge_to([clip_l, t5xxl], model, weights_sd)
else:
lora_model.apply_to([clip_l, t5xxl], model)
info = lora_model.load_state_dict(weights_sd, strict=True)
logger.info(f"Loaded LoRA weights from {weights_file}: {info}")
lora_model.eval()
lora_model.to(device)
lora_models.append(lora_model)
if not args.interactive:
generate_image(model, clip_l, t5xxl, ae, args.prompt, args.seed, args.width, args.height, args.steps, args.guidance)
else:
# loop for interactive
width = target_width
height = target_height
steps = None
guidance = args.guidance
while True:
print(
"Enter prompt (empty to exit). Options: --w <width> --h <height> --s <steps> --d <seed> --g <guidance> --m <multipliers for LoRA>"
)
prompt = input()
if prompt == "":
break
# parse options
options = prompt.split("--")
prompt = options[0].strip()
seed = None
for opt in options[1:]:
opt = opt.strip()
if opt.startswith("w"):
width = int(opt[1:].strip())
elif opt.startswith("h"):
height = int(opt[1:].strip())
elif opt.startswith("s"):
steps = int(opt[1:].strip())
elif opt.startswith("d"):
seed = int(opt[1:].strip())
elif opt.startswith("g"):
guidance = float(opt[1:].strip())
elif opt.startswith("m"):
mutipliers = opt[1:].strip().split(",")
if len(mutipliers) != len(lora_models):
logger.error(f"Invalid number of multipliers, expected {len(lora_models)}")
continue
for i, lora_model in enumerate(lora_models):
lora_model.set_multiplier(float(mutipliers[i]))
generate_image(model, clip_l, t5xxl, ae, prompt, seed, width, height, steps, guidance)
logger.info("Done!")