from collections import deque import torch import inspect import k_diffusion.sampling from modules import prompt_parser, devices, sd_samplers_common from modules.shared import opts, state import modules.shared as shared from modules.script_callbacks import CFGDenoiserParams, cfg_denoiser_callback from modules.script_callbacks import CFGDenoisedParams, cfg_denoised_callback samplers_k_diffusion = [ ('Euler a', 'sample_euler_ancestral', ['k_euler_a', 'k_euler_ancestral'], {}), ('Euler', 'sample_euler', ['k_euler'], {}), ('LMS', 'sample_lms', ['k_lms'], {}), ('Heun', 'sample_heun', ['k_heun'], {}), ('DPM2', 'sample_dpm_2', ['k_dpm_2'], {'discard_next_to_last_sigma': True}), ('DPM2 a', 'sample_dpm_2_ancestral', ['k_dpm_2_a'], {'discard_next_to_last_sigma': True}), ('DPM++ 2S a', 'sample_dpmpp_2s_ancestral', ['k_dpmpp_2s_a'], {}), ('DPM++ 2M', 'sample_dpmpp_2m', ['k_dpmpp_2m'], {}), ('DPM++ SDE', 'sample_dpmpp_sde', ['k_dpmpp_sde'], {}), ('DPM fast', 'sample_dpm_fast', ['k_dpm_fast'], {}), ('DPM adaptive', 'sample_dpm_adaptive', ['k_dpm_ad'], {}), ('LMS Karras', 'sample_lms', ['k_lms_ka'], {'scheduler': 'karras'}), ('DPM2 Karras', 'sample_dpm_2', ['k_dpm_2_ka'], {'scheduler': 'karras', 'discard_next_to_last_sigma': True}), ('DPM2 a Karras', 'sample_dpm_2_ancestral', ['k_dpm_2_a_ka'], {'scheduler': 'karras', 'discard_next_to_last_sigma': True}), ('DPM++ 2S a Karras', 'sample_dpmpp_2s_ancestral', ['k_dpmpp_2s_a_ka'], {'scheduler': 'karras'}), ('DPM++ 2M Karras', 'sample_dpmpp_2m', ['k_dpmpp_2m_ka'], {'scheduler': 'karras'}), ('DPM++ SDE Karras', 'sample_dpmpp_sde', ['k_dpmpp_sde_ka'], {'scheduler': 'karras'}), ] samplers_data_k_diffusion = [ sd_samplers_common.SamplerData(label, lambda model, funcname=funcname: KDiffusionSampler(funcname, model), aliases, options) for label, funcname, aliases, options in samplers_k_diffusion if hasattr(k_diffusion.sampling, funcname) ] sampler_extra_params = { 'sample_euler': ['s_churn', 's_tmin', 's_tmax', 's_noise'], 'sample_heun': ['s_churn', 's_tmin', 's_tmax', 's_noise'], 'sample_dpm_2': ['s_churn', 's_tmin', 's_tmax', 's_noise'], } class CFGDenoiser(torch.nn.Module): """ Classifier free guidance denoiser. A wrapper for stable diffusion model (specifically for unet) that can take a noisy picture and produce a noise-free picture using two guidances (prompts) instead of one. Originally, the second prompt is just an empty string, but we use non-empty negative prompt. """ def __init__(self, model): super().__init__() self.inner_model = model self.mask = None self.nmask = None self.init_latent = None self.step = 0 self.image_cfg_scale = None def combine_denoised(self, x_out, conds_list, uncond, cond_scale): denoised_uncond = x_out[-uncond.shape[0]:] denoised = torch.clone(denoised_uncond) for i, conds in enumerate(conds_list): for cond_index, weight in conds: denoised[i] += (x_out[cond_index] - denoised_uncond[i]) * (weight * cond_scale) return denoised def combine_denoised_for_edit_model(self, x_out, cond_scale): out_cond, out_img_cond, out_uncond = x_out.chunk(3) denoised = out_uncond + cond_scale * (out_cond - out_img_cond) + self.image_cfg_scale * (out_img_cond - out_uncond) return denoised def forward(self, x, sigma, uncond, cond, cond_scale, s_min_uncond, image_cond): if state.interrupted or state.skipped: raise sd_samplers_common.InterruptedException # at self.image_cfg_scale == 1.0 produced results for edit model are the same as with normal sampling, # so is_edit_model is set to False to support AND composition. is_edit_model = shared.sd_model.cond_stage_key == "edit" and self.image_cfg_scale is not None and self.image_cfg_scale != 1.0 conds_list, tensor = prompt_parser.reconstruct_multicond_batch(cond, self.step) uncond = prompt_parser.reconstruct_cond_batch(uncond, self.step) assert not is_edit_model or all([len(conds) == 1 for conds in conds_list]), "AND is not supported for InstructPix2Pix checkpoint (unless using Image CFG scale = 1.0)" batch_size = len(conds_list) repeats = [len(conds_list[i]) for i in range(batch_size)] if shared.sd_model.model.conditioning_key == "crossattn-adm": image_uncond = torch.zeros_like(image_cond) make_condition_dict = lambda c_crossattn, c_adm: {"c_crossattn": c_crossattn, "c_adm": c_adm} else: image_uncond = image_cond make_condition_dict = lambda c_crossattn, c_concat: {"c_crossattn": c_crossattn, "c_concat": [c_concat]} if not is_edit_model: x_in = torch.cat([torch.stack([x[i] for _ in range(n)]) for i, n in enumerate(repeats)] + [x]) sigma_in = torch.cat([torch.stack([sigma[i] for _ in range(n)]) for i, n in enumerate(repeats)] + [sigma]) image_cond_in = torch.cat([torch.stack([image_cond[i] for _ in range(n)]) for i, n in enumerate(repeats)] + [image_uncond]) else: x_in = torch.cat([torch.stack([x[i] for _ in range(n)]) for i, n in enumerate(repeats)] + [x] + [x]) sigma_in = torch.cat([torch.stack([sigma[i] for _ in range(n)]) for i, n in enumerate(repeats)] + [sigma] + [sigma]) image_cond_in = torch.cat([torch.stack([image_cond[i] for _ in range(n)]) for i, n in enumerate(repeats)] + [image_uncond] + [torch.zeros_like(self.init_latent)]) denoiser_params = CFGDenoiserParams(x_in, image_cond_in, sigma_in, state.sampling_step, state.sampling_steps, tensor, uncond) cfg_denoiser_callback(denoiser_params) x_in = denoiser_params.x image_cond_in = denoiser_params.image_cond sigma_in = denoiser_params.sigma tensor = denoiser_params.text_cond uncond = denoiser_params.text_uncond skip_uncond = False # alternating uncond allows for higher thresholds without the quality loss normally expected from raising it if self.step % 2 and s_min_uncond > 0 and sigma[0] < s_min_uncond and not is_edit_model: skip_uncond = True x_in = x_in[:-batch_size] sigma_in = sigma_in[:-batch_size] if tensor.shape[1] == uncond.shape[1] or skip_uncond: if is_edit_model: cond_in = torch.cat([tensor, uncond, uncond]) elif skip_uncond: cond_in = tensor else: cond_in = torch.cat([tensor, uncond]) if shared.batch_cond_uncond: x_out = self.inner_model(x_in, sigma_in, cond=make_condition_dict([cond_in], image_cond_in)) else: x_out = torch.zeros_like(x_in) for batch_offset in range(0, x_out.shape[0], batch_size): a = batch_offset b = a + batch_size x_out[a:b] = self.inner_model(x_in[a:b], sigma_in[a:b], cond=make_condition_dict([cond_in[a:b]], image_cond_in[a:b])) else: x_out = torch.zeros_like(x_in) batch_size = batch_size*2 if shared.batch_cond_uncond else batch_size for batch_offset in range(0, tensor.shape[0], batch_size): a = batch_offset b = min(a + batch_size, tensor.shape[0]) if not is_edit_model: c_crossattn = [tensor[a:b]] else: c_crossattn = torch.cat([tensor[a:b]], uncond) x_out[a:b] = self.inner_model(x_in[a:b], sigma_in[a:b], cond=make_condition_dict(c_crossattn, image_cond_in[a:b])) if not skip_uncond: x_out[-uncond.shape[0]:] = self.inner_model(x_in[-uncond.shape[0]:], sigma_in[-uncond.shape[0]:], cond=make_condition_dict([uncond], image_cond_in[-uncond.shape[0]:])) denoised_image_indexes = [x[0][0] for x in conds_list] if skip_uncond: fake_uncond = torch.cat([x_out[i:i+1] for i in denoised_image_indexes]) x_out = torch.cat([x_out, fake_uncond]) # we skipped uncond denoising, so we put cond-denoised image to where the uncond-denoised image should be denoised_params = CFGDenoisedParams(x_out, state.sampling_step, state.sampling_steps) cfg_denoised_callback(denoised_params) devices.test_for_nans(x_out, "unet") if opts.live_preview_content == "Prompt": sd_samplers_common.store_latent(torch.cat([x_out[i:i+1] for i in denoised_image_indexes])) elif opts.live_preview_content == "Negative prompt": sd_samplers_common.store_latent(x_out[-uncond.shape[0]:]) if is_edit_model: denoised = self.combine_denoised_for_edit_model(x_out, cond_scale) elif skip_uncond: denoised = self.combine_denoised(x_out, conds_list, uncond, 1.0) else: denoised = self.combine_denoised(x_out, conds_list, uncond, cond_scale) if self.mask is not None: denoised = self.init_latent * self.mask + self.nmask * denoised self.step += 1 return denoised class TorchHijack: def __init__(self, sampler_noises): # Using a deque to efficiently receive the sampler_noises in the same order as the previous index-based # implementation. self.sampler_noises = deque(sampler_noises) def __getattr__(self, item): if item == 'randn_like': return self.randn_like if hasattr(torch, item): return getattr(torch, item) raise AttributeError(f"'{type(self).__name__}' object has no attribute '{item}'") def randn_like(self, x): if self.sampler_noises: noise = self.sampler_noises.popleft() if noise.shape == x.shape: return noise if opts.randn_source == "CPU" or x.device.type == 'mps': return torch.randn_like(x, device=devices.cpu).to(x.device) else: return torch.randn_like(x) class KDiffusionSampler: def __init__(self, funcname, sd_model): denoiser = k_diffusion.external.CompVisVDenoiser if sd_model.parameterization == "v" else k_diffusion.external.CompVisDenoiser self.model_wrap = denoiser(sd_model, quantize=shared.opts.enable_quantization) self.funcname = funcname self.func = getattr(k_diffusion.sampling, self.funcname) self.extra_params = sampler_extra_params.get(funcname, []) self.model_wrap_cfg = CFGDenoiser(self.model_wrap) self.sampler_noises = None self.stop_at = None self.eta = None self.config = None self.last_latent = None self.s_min_uncond = None self.conditioning_key = sd_model.model.conditioning_key def callback_state(self, d): step = d['i'] latent = d["denoised"] if opts.live_preview_content == "Combined": sd_samplers_common.store_latent(latent) self.last_latent = latent if self.stop_at is not None and step > self.stop_at: raise sd_samplers_common.InterruptedException state.sampling_step = step shared.total_tqdm.update() def launch_sampling(self, steps, func): state.sampling_steps = steps state.sampling_step = 0 try: return func() except sd_samplers_common.InterruptedException: return self.last_latent def number_of_needed_noises(self, p): return p.steps def initialize(self, p): self.model_wrap_cfg.mask = p.mask if hasattr(p, 'mask') else None self.model_wrap_cfg.nmask = p.nmask if hasattr(p, 'nmask') else None self.model_wrap_cfg.step = 0 self.model_wrap_cfg.image_cfg_scale = getattr(p, 'image_cfg_scale', None) self.eta = p.eta if p.eta is not None else opts.eta_ancestral self.s_min_uncond = getattr(p, 's_min_uncond', 0.0) k_diffusion.sampling.torch = TorchHijack(self.sampler_noises if self.sampler_noises is not None else []) extra_params_kwargs = {} for param_name in self.extra_params: if hasattr(p, param_name) and param_name in inspect.signature(self.func).parameters: extra_params_kwargs[param_name] = getattr(p, param_name) if 'eta' in inspect.signature(self.func).parameters: if self.eta != 1.0: p.extra_generation_params["Eta"] = self.eta extra_params_kwargs['eta'] = self.eta return extra_params_kwargs def get_sigmas(self, p, steps): discard_next_to_last_sigma = self.config is not None and self.config.options.get('discard_next_to_last_sigma', False) if opts.always_discard_next_to_last_sigma and not discard_next_to_last_sigma: discard_next_to_last_sigma = True p.extra_generation_params["Discard penultimate sigma"] = True steps += 1 if discard_next_to_last_sigma else 0 if p.sampler_noise_scheduler_override: sigmas = p.sampler_noise_scheduler_override(steps) elif self.config is not None and self.config.options.get('scheduler', None) == 'karras': sigma_min, sigma_max = (0.1, 10) if opts.use_old_karras_scheduler_sigmas else (self.model_wrap.sigmas[0].item(), self.model_wrap.sigmas[-1].item()) sigmas = k_diffusion.sampling.get_sigmas_karras(n=steps, sigma_min=sigma_min, sigma_max=sigma_max, device=shared.device) else: sigmas = self.model_wrap.get_sigmas(steps) if discard_next_to_last_sigma: sigmas = torch.cat([sigmas[:-2], sigmas[-1:]]) return sigmas def create_noise_sampler(self, x, sigmas, p): """For DPM++ SDE: manually create noise sampler to enable deterministic results across different batch sizes""" if shared.opts.no_dpmpp_sde_batch_determinism: return None from k_diffusion.sampling import BrownianTreeNoiseSampler sigma_min, sigma_max = sigmas[sigmas > 0].min(), sigmas.max() current_iter_seeds = p.all_seeds[p.iteration * p.batch_size:(p.iteration + 1) * p.batch_size] return BrownianTreeNoiseSampler(x, sigma_min, sigma_max, seed=current_iter_seeds) def sample_img2img(self, p, x, noise, conditioning, unconditional_conditioning, steps=None, image_conditioning=None): steps, t_enc = sd_samplers_common.setup_img2img_steps(p, steps) sigmas = self.get_sigmas(p, steps) sigma_sched = sigmas[steps - t_enc - 1:] xi = x + noise * sigma_sched[0] extra_params_kwargs = self.initialize(p) parameters = inspect.signature(self.func).parameters if 'sigma_min' in parameters: ## last sigma is zero which isn't allowed by DPM Fast & Adaptive so taking value before last extra_params_kwargs['sigma_min'] = sigma_sched[-2] if 'sigma_max' in parameters: extra_params_kwargs['sigma_max'] = sigma_sched[0] if 'n' in parameters: extra_params_kwargs['n'] = len(sigma_sched) - 1 if 'sigma_sched' in parameters: extra_params_kwargs['sigma_sched'] = sigma_sched if 'sigmas' in parameters: extra_params_kwargs['sigmas'] = sigma_sched if self.funcname == 'sample_dpmpp_sde': noise_sampler = self.create_noise_sampler(x, sigmas, p) extra_params_kwargs['noise_sampler'] = noise_sampler self.model_wrap_cfg.init_latent = x self.last_latent = x extra_args={ 'cond': conditioning, 'image_cond': image_conditioning, 'uncond': unconditional_conditioning, 'cond_scale': p.cfg_scale, 's_min_uncond': self.s_min_uncond } samples = self.launch_sampling(t_enc + 1, lambda: self.func(self.model_wrap_cfg, xi, extra_args=extra_args, disable=False, callback=self.callback_state, **extra_params_kwargs)) return samples def sample(self, p, x, conditioning, unconditional_conditioning, steps=None, image_conditioning=None): steps = steps or p.steps sigmas = self.get_sigmas(p, steps) x = x * sigmas[0] extra_params_kwargs = self.initialize(p) parameters = inspect.signature(self.func).parameters if 'sigma_min' in parameters: extra_params_kwargs['sigma_min'] = self.model_wrap.sigmas[0].item() extra_params_kwargs['sigma_max'] = self.model_wrap.sigmas[-1].item() if 'n' in parameters: extra_params_kwargs['n'] = steps else: extra_params_kwargs['sigmas'] = sigmas if self.funcname == 'sample_dpmpp_sde': noise_sampler = self.create_noise_sampler(x, sigmas, p) extra_params_kwargs['noise_sampler'] = noise_sampler self.last_latent = x samples = self.launch_sampling(steps, lambda: self.func(self.model_wrap_cfg, x, extra_args={ 'cond': conditioning, 'image_cond': image_conditioning, 'uncond': unconditional_conditioning, 'cond_scale': p.cfg_scale, 's_min_uncond': self.s_min_uncond }, disable=False, callback=self.callback_state, **extra_params_kwargs)) return samples