diff --git a/README.md b/README.md index 3ae6f50..cf73fed 100644 --- a/README.md +++ b/README.md @@ -1,2 +1,21 @@ -# ComfyUI-dpmpp_2m_alt-Sampler -DPM++ 2M alt Sampler for ComfyUI + + +# ComfyUI DPM++ 2M Alt Sampler + +the sampler introduced by [hallatore](https://github.com/AUTOMATIC1111/stable-diffusion-webui/discussions/8457) + +code extracted from [smZNodes](https://github.com/shiimizu/ComfyUI_smZNodes) diff --git a/__init__.py b/__init__.py new file mode 100644 index 0000000..04baad4 --- /dev/null +++ b/__init__.py @@ -0,0 +1,20 @@ +# Copyright 2024 SLAPaper +# +# 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 +# +# https://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. + +from .alt_sampler import add_custom_samplers + +add_custom_samplers() + + +NODE_CLASS_MAPPINGS = {} diff --git a/alt_sampler.py b/alt_sampler.py new file mode 100644 index 0000000..b088e38 --- /dev/null +++ b/alt_sampler.py @@ -0,0 +1,75 @@ +# Copyright 2024 SLAPaper +# +# 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 +# +# https://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 torch +from tqdm.auto import trange + + +@torch.no_grad() +def sample_dpmpp_2m_alt(model, x, sigmas, extra_args=None, callback=None, disable=None): + """DPM-Solver++(2M) alt""" + extra_args = {} if extra_args is None else extra_args + s_in = x.new_ones([x.shape[0]]) + sigma_fn = lambda t: t.neg().exp() + t_fn = lambda sigma: sigma.log().neg() + old_denoised = None + + for i in trange(len(sigmas) - 1, disable=disable): + denoised = model(x, sigmas[i] * s_in, **extra_args) + if callback is not None: + callback( + { + "x": x, + "i": i, + "sigma": sigmas[i], + "sigma_hat": sigmas[i], + "denoised": denoised, + } + ) + t, t_next = t_fn(sigmas[i]), t_fn(sigmas[i + 1]) + h = t_next - t + if old_denoised is None or sigmas[i + 1] == 0: + x = (sigma_fn(t_next) / sigma_fn(t)) * x - (-h).expm1() * denoised + else: + h_last = t - t_fn(sigmas[i - 1]) + r = h_last / h + denoised_d = (1 + 1 / (2 * r)) * denoised - (1 / (2 * r)) * old_denoised + x = (sigma_fn(t_next) / sigma_fn(t)) * x - (-h).expm1() * denoised_d + sigma_progress = i / len(sigmas) + adjustment_factor = 1 + (0.15 * (sigma_progress * sigma_progress)) + old_denoised = denoised * adjustment_factor + return x + + +def add_sample_dpmpp_2m_alt(): + from comfy.samplers import KSampler, k_diffusion_sampling + + if "dpmpp_2m_alt" not in KSampler.SAMPLERS: + try: + idx = KSampler.SAMPLERS.index("dpmpp_2m") + KSampler.SAMPLERS.insert(idx + 1, "dpmpp_2m_alt") + setattr(k_diffusion_sampling, "sample_dpmpp_2m_alt", sample_dpmpp_2m_alt) + import importlib + + importlib.reload(k_diffusion_sampling) + except ValueError: + pass + + +def add_custom_samplers(): + samplers = [ + add_sample_dpmpp_2m_alt, + ] + for add_sampler in samplers: + add_sampler()